Explaining the effects of frame geometries

I see frame geometry having 3 primary affects

Fitting the rider; which you're already addressing and I won't talk about here...  But a lot of geometry stuff comes down to making the other stuff work with fitting riders on the bikes. It's very important.
Fitting stuff on the bike
Handling characteristics.

Since you asked, I'm talking about your basic on-road diamond-frame bike. Cruiser, road, commuter, urban, touring, racer...
Fitting Stuff On the Bike

Wheel clearance affects how big the tires can be and how easy it is to mount fenders. For the rear wheel you need to look at the chainstay bridge, seatstay bridge and seat tube. For the front wheel, look at the fork crown and downtube. Often either not measured or simply given to you as a maximum tire size measurement.
"Toe overlap" -- how close the front wheel gets to the front of the pedals. More of an issue with fenders, and not really an issue once you're going any kind of speed. I never see this on the geometry specs from manufacturers, but definitely worth checking. You can get used to moderate toe overlap, though.
Longer chainstay length gives you more heel clearance for loading panniers on the rear rack. I know from personal experience that the most likely place to kick a pannier off the rack is in an intersection, so if you plan to carry panniers this can be very important. Short chainstay length can be compensated for by getting a rack that allows panniers to be mounted further back (longer top, top further back, however they do it).

Handling characteristics
First off, the way a bike handles, "stability" and "maneuverability" are essentially opposites. It's a tradeoff. Whether you want stable or maneuverable depends on what you're going to do with the bike, how fast you'll be going, your riding experience, etc. And there's some more complicated harder-to-understand secondary effects.
I really think that for most of the handling stuff you're best off just test-riding bikes that fit you. Experiment with the handling. Try going slow. Try going fast. Try making a sharp turn. Try making a subtle turn. Try a dodge/weave. Try those turns at different speeds. Try a fast start. Try a fast stop. Try all that in all the handlebar positions. Unless you're designing a bike, a lot of this is all very theoretical, heavily interrelated (can't really change one variable without changing the others), and likely to be very small differences when comparing actual bikes.

Bottom Bracket (BB) height (sometimes you can find this out, sometimes you have to make a guess based on wheel+tire radius minus BB drop).  Higher bottom bracket makes it easier to go over stuff. Not really an issue if you stick to roads, but can be a factor when trying to pedal through sharp turns. Higher BB also lets you use longer cranks which some people want. Compare a Cyclocross to a Road bike and the CX bike will have a higher BB.

Wheelbase length (distance between hubs/contact patches). A longer wheelbase will make the bike more longitudinally stable. In other words, less prone to wheelies and less prone to flipping you over the handlebars.  This could theoretically translate to better ability to stop faster. Note that one way to give you a longer wheelbase is longer chainstays. The position of your center of gravity makes a big difference, too.

Headtube angle (steering axis angle). A shallower/slacker (more pointed forward) angle gives you more trail. A shallower angle also increases how much the weight can make the wheel flop on its own and negatively affect stability at low speed. This is usually measured from horizontal, so a steep angle will be closer to 90° and a shallow angle will be a lower number.

Fork offset/rake (how far the front hub is in front of the steering axis). More offset gives you less trail. More offset also tends to give you more toe clearance.

Trail is how far the front contact patch is behind the steering axis. Note that while the trail is the important measurement, the headtube angle and fork offset (and wheel size) are what determines the trail. A bicycle with no trail would be unrideable (but many people like having very little trail).
There's different ways of measuring the trail (along the ground, or perpendicular to the steering axis) that make comparisons more intuitive, but more trail means more stable, and less trail means more maneuverable. Or to put it another way: less trail means more twitch and more trail means less responsive.
The stability from trail increases as the bicycle goes faster. If you look at some cruiser bikes they'll tend to have a shallow headtube angle and a lot of trail: they're stable and easy to balance at low speeds but probably hard to steer at high speed. If you look at a road/racing bike, the headtube angle is usually much closer to vertical and the trail is fairly small: they may feel unstable and wobbly (hard to balance) at low speeds, but are still easy to steer (responsive) at high speeds.
Note also that the handlebar setup and rider preferences/experience make a huge difference whether your prefer maneuverable/twitchy/responsive or stable/unsteerable/unresponsive.

References

http://en.wikipedia.org/wiki/Bicycle_and_motorcycle_dynamics


Wheel rim looks smaller than what the fork is designed for.

Is that an old road frame? Perhaps it was made for an ISO 630mm rim (sometimes called a 27 inch) but you have installed a wheel with a 700c/ISO 622mm rim.


The question has been changed since this answer was posted.

On an 85° grade you would approach terminal velocity for a sky diver of about 120 mph.

It does not need to be endless. You approach terminal velocity pretty quickly.


What type of bicycle would be the most suitable for riding in winter in the city?

I've commuted through two winters in the Pacific Northwest and I have learned how to be prepared for winter wet, snow and ice. In general, my advice:

fenders...or love your mud stripe, in fact, I extend my fenders with panels cut from milk jugs
ziplock pogies if you need them
glasses (keeps the rain out of your eyes, and car splash too)
a full sized bike with a rack really helps because you have a place to put your layers or a change of clothes
if you expect ice, which loves to live on shady, unplowed residential streets, a pair of studded tires is a wise investment (I have a pair of Schwalbe Marathon Winters)
lights: winter commuting puts me on the road before sunrise and after sunset, I need to be visible
your patch kit and pump: I have had more flats in wet weather because wet rubber cuts far more easily than dry rubber. Sharp gravel, nails, beer bottles, whatever it is, I'm more likely to get a flat in wet weather.

I have not found that tire size, or tire tread has made significant difference to me, I have learned you cannot ride on a snowy shoulder, you want to ride on the least snow or ice possible, otherwise you might just slide into the gully. Studs don't help with snow, deep tread might. For plain old wet weather, I have had no trouble with road tires, I didn't get any advantage from knobbies, in fact I replaced my MTB tires with road tires.

Good luck with your commute!


Going to race a 29er MTB in a 200 mile / 320 km gravel race. Bike preparation?

Between mass and aerodynamics you would be expending a ton more energy on the MTB if the roads are in decent shape. Rather than roadify the MTB you might consider MTBifying a road bike.  Tires are the key, really large, supple ones to soak up the bumps, at an appropriate pressure. Perhaps aiming for tubular cx tires that you can run really low pressures on.


How Can I Prevent Slime Barrel Pumps from Clogging?

I have no way of knowing if this will work with Slime but I have done something similar in industrial applications.

You will need a "T" fitting and two shutoff valves. Install the valves on to the "T",one on the bottom port of the "T" and the other to a side port. Install the side port valve on the Slime hose as close to the pump as possible. Connect the remaining Slime hose to the remaining side port of the "T". Attach a compressed airline to the bottom port valve.

To fill a tire shut off the bottom port valve. Open the side port valve. Fill the tire as you did before. When your done shut off the Slime pump and close the side port valve. Open the bottom port valve and apply enough compressed air to blow the remaining Slime from the Slime fill hose. The Slime in the hose that is between the pump and the valve should stay liquid as it has no exposure to air.


Why does reducing bike weight have such an impact on speeds?

The two major "drags" on a bike, on level ground, are the rolling resistance of the tires and the wind resistance of the bike and rider.

In general, up to a point, a tire with higher pressure will have lower rolling resistance, as will a tire with a smoother tread.  Tire width also figures in, but mostly in terms of how it influences pressure and tread.

Wind resistance is affected by tire width, number of spokes, tube size, and rider position.  Generally, as the "raciness" of a bike increases, tire width and spoke count decrease and rider position becomes more prone (and hence more aerodynamic).  Tube size doesn't tend to vary much (and may actually increase as you go steel->aluminum->carbon) but that effect is slight and subtle differences in frame design can be more significant.

There may also be ergonomic changes -- eg, the more prone riding position, while more fatiguing, is often somewhat better for peak power output.

Bearing quality hardly figures in at all.  Even cheapo bearings have very low losses, and the difference in drag between them and top-of-the-line bearings is not likely to be measurable.  (The bigger difference is in durability.)

Bike weight only comes into the equation when one must "climb" (and to a very minor degree for rolling resistance), but of course it's rare to have a route that does not go up/down by 0.5% or so most of the time.  That 0.5% increases the power required to hold a steady speed by about 10% over a dead-level course.  But the 3KG difference between the above two bikes would amount to about a 0.4% power difference on that 0.5% slope.


How to build a Camping trailer, and riding across country with it

I haven't built a bike trailer but used a B.O.B. Yak for a trip from the UK down through Europe.  It was a great trailer and we were able to fit a large 2-man tent in there plus other stuff.  We also had front and back panniers.

See here:  http://www.bobgear.com/bike-trailers/yak

I now use a Burley D'Lite with 2 toddlers in it.  Even though you could fit more stuff in it than the B.O.B. I would be wary of getting the centre of gravity too high.

See here: http://www.burley.com/page_308/dlite-p308

The thing to bear in mind is that these companies have researched the handling, aerodynamics, load bearing, etc which is something that you'd need to consider.

For touring I'd say the Yak is the way to go as it is designed and built specifically for this use.

Edit: Also, bought trailers come complete with the things you need to attach it to your bike.


Is there anything special to pay attention to when preparing a bicycle for powdercoating?

You'll definitely need to remove all components.  For threaded bits you have two choices - leave junk bolts in there that will get powdercoated over and then carefully remove them (leaving a bit of an edge around the bolt hole) or let them get masked but almost certainly somewhat powdercoated into and use a tap and die set to chase them before reassembly.  Be prepared to face/ream/chase the headtube and bottom bracket in any case.

Do make sure you've cleaned it as much as possible, removing any residual grease and road dirt.  I wouldn't worry about the stickers and decals, the media blasting to prepare the frame should take care of that.  With the relatively low cost of media blasting I wouldn't bother trying to strip the paint myself.

Make sure you find a powdercoater that is familiar with bicycle frames; particularly when it comes to media blasting they need to understand how thin the tubing is.


Upgrading From Ultegra 6600 to 6800 Help

The crank end generally is fine. Pre- and post-super SLR brakes and levers don't work together because they changed the cable pull. Presuming you have a 10-speed rear wheel, it can't take an 11-speed road cassette.


Short answer: No, you shouldn't. Heavy oils attract too much dirt, grit and grime which will damage the useful life of your chain.

You need a light lubricant which will wick it's way into the internals of the chain, rather than simply coating the external portion of the chain.

A good Teflon carrier lube like the Finish Line Teflon works well, lasts a good while and doesn't pick up dirt when properly applied. Using something like that will extend the useful life of your chain.

Gear oil is too thick, and designed for a higher heat production than you get on a pedal driven bicycle. It relies on engine heat, and the gears moving at high speed to produce enough friction to reduce the viscosity of the oil enough to be thin enough to flow as a good lubricant.

It would be better than nothing, but hardly a good choice.


It turns out that the "washer" is upside down in the photo: The flanges on the sides of the washer are perfectly flat on one side but are slightly curved on the other. By flipping the washer over so that the flat side faces the bell and the curved side faces the handlebar, the flanges then protrude ever-so-slightly away from the handlebars. With this slight difference, there is enough friction between the edges of the flanges and the respective edges of the holes in the bracket to catch and hold the bracket in place.

In order to put the washer in place on the screw so that it can be tightened, a flathead screwdriver can be placed between the handlebar itself and the washer, gently pushing the washer upwards towards the screw and holding it in place while the screw is tightened. Once the screw is tightened enough, the flanges will catch on the holes in the bracket and then begin to pull the ends of bracket together, which will then keep the bell securely on the handlebar through this tension.


What are the most common causes for hysteresis in the rear derailler?

Here is the list of things I usually check for when troubleshooting jumping gears:

Is the chain always goes up/down? In this case usually the adjustment is off. Try adjust the cable.
Is the mech hanger bent? Sometimes during a crash you can bend a mech hanger. Most of the times you can bend it back, but there are cases where you need to replace the mech hanger for a new one. Usually they are cheap £5-15.
Is the shifting very slow? Dirty outer cables and rusty inner can cause the problem with shifting. Replace inner cable and outer cable for new ones.
Is the shifter clicking OK? I've seen cheap shifter wearing out and not "holding" clicks properly, so the chain would jump.
Are the mech cogs (small chainrings) worn out? are they wobbly? Chain can only be placed properly if the cog is not moving sideways. If that is the case, replace the top cog. Also worn out cog can affect the shifting performance.
Is the mech itself not bent or otherwise damaged? There are plenty of ways to destroy the mech.. usually that is beyond repair and you need to get a new one.
If the mech is very-very cheap, it sometimes gets bent while in normal use (not MTB abuse). Only replacement will fix that.

Good luck! And I'm off to fix my wife's bike gears -)


Tick sound on every pedal only for 5 minutes

Possible cause:

Without any further knowledge about your bike, I'd guess that the clicking noise has something to make with a grease in either the pedal or the crank bearings. (As you mentioned that the sound occurs only when the pedals are in the very same position and when you actually put some force on them, I'd say it isn't caused by something like an unevenly tightend handle bar or loose seat post etc etc..)

Since you only hear the clicks within the first 5 - 10 min when riding, I assume this is the time the grease needs to "warm up", as in become slightly more fluid due to the friction it experiences. During this time some of the little balls inside the bearings could cause the clicking noises.

Possible solution:

Make sure that the pedal bearings arent tightend too much (in case
you can open them at all).
check on your cranks, whether they're tightend properly
check on the more unlikely sources for the click (i.e. seat post, saddle, etc.)
replace bottom bracket

I'd also advice you to do these steps iteratively, so you get to know the source of the problem.


Change chain with cassette or do nothing?

If chain wear is beyond 1% then you are probably looking at a new drivetrain including chainrings. I would just remount the old chain and get the full wear out of everything else.
As far as changing chain only the industry standard is wear between 0.5-0.75% if you change within this range the theory is you will prolong the life of the drivetrain and perhaps never have to change anything except the chain.
The likelihood of snapping a chain is not very high for normal everyday use.


@Victor this can be made to work.

The new crank has a GXP interface spindle, you can notice that by a notch before NDS arm splines start, which serves as a stops against inner bearing race, and the fact that splines are on non-drive side (SRAM BB30 splines are on drive-side). Since GXP is a Truvativ/SRAM variation on 24mm spindle, it should fit everywhere Shimano 24mm Hollowtech II fits. The spindle length is no problem, BB30 bottom bracket shells are the narrowest (68mm, FC-6800 is designed around 86mm bearings stance), so with the right bottom bracket you could install almost any crank, so all you need is a BB30 to GXP bottom bracket.


That is a semi integrated head tube to be used with semi integrated head set, a fully integrated head tubes machining is different , it would have a precis depth and an 45 degree angle to it , in order to match fully integrated bearings and yield a exact final bearing depth . When useing a semi integrated system the cup or race you press into the head tube takes the place of this precision machining of the head tube.


Commuting daily with an Expensive Bike, tips?

I think that picking up a second bike is definitely a good approach. Not only does it allow you to not risk your more expensive bike getting stolen, but it allows you to  have a bike more suitable to commuting. You can put fenders and racks on your commuting bike.  Perhaps wider tires if you want something a little more comfortable.  Since you are good with a single speed, this can also be very advantageous on a commuting bike because they are extremely reliable as there are much fewer parts that can have something go wrong with them.


You need a rear hub that can have a cog on both sides.

Some fixed gear hubs have threads on both sides, or a fixed thread on one side and freewheel thread on the other. The author apparently has one of these.

The multi-gear option is to use a disc hub and cog that has been drilled to fit 6-bolt disc brake mount. This trick is usually used to make fixed gear hubs out of MTB front hubs, but could also work here.


From a theoretical point of view, there are some possible methods to take water out of a fabric object, such as a shoe:

"Replacing" the water for another, faster drying liquid and letting it evaporate;
Squeezing the water out directly by compression and twisting (not usually adviseable);
"Force field" like gravity and centrifugation;
Capilary action (which is what the newspaper does);
Thermal action (sun, heater);
Wind action (free-air, fan).

The last two increase the rate of evaporation, the first by increasing the internal energy of water, the later by reducing the relative humidity of the air layer close to the fabric.

Then (always theoretically) one possible way to dry a shoe quickly would be to force-circulate warm, dry air inside a newspaper filled shoe that has been previously centrifugated/squeezed after being rinsed in warm water with a bit of alchohol.

The problem that still persists is how to actually implement this air heating and circulation without a complicated device or combination of devices...

I use to put newspaper inside as you described, but for the first three stuffings, I squeeze firmly (stepping over if necessary) so that most the moisture is mechanically removed. Then I put extra, dry newspaper and leave the shoes hanging in the open air. Unfortunately, depending on weather conditions, this not always work.


To be very to-the-point, in your situation I would first consider the following two things:

Rise/exchange your handlebar to leave it at least some 8 inches above the saddle height;
Have a good quality suspension seatpost.

I have studied medicine (and have a little back pain, also), so the rationale is the following:

This figure illustrates a part of the lumbar spine, as would be seen if the rider was passing from right to left on the bike (left is front, right is back).

Rising the handlebar would allow you to be more erect, thus making the upper vertebrae rotate backwards (clockwise in the figure) over the lower vertebrae. Since this rotation is articulated a bit behind the midline, there is a decompression of the discs (blue and red, with red being herniae and blue being normal disc tissue);
Since your bar is now higher, a greater part of your body weight is supported by your back/buttocks. Using a suspended seatpost - a relatively lowcost, minimal modification on your current rigid bike - helps avoding unpredicted/unavoidable impact, which is a main causation factor of hernia inflamation and/or progression, due to the sudden rises on internal disc pressure associated with impact.

I don't enjoy very much the feeling of sprung saddles (I have a Brooks Flyer), and I think that's because they pivot around the nose, thus bending the lower back and pelvis while going down, in a flexing motion. Seatposts, on the other side, have a translation movement, without pelvis rotation.

Having ridden some suspended-seatpost-equipped bikes, I can say one thing: they are awesome! And since you have a condition, thus are probably not wanting to become world champion anymore, the minimal, questionable performance decrease is overwhelmed by the very significant gains in comfort and health risk reduction.

Hope this helps!


Cant get my rear derailleur to reach all cogs

As you suggested, the cable may be at fault.  I change my gear cables once or twice a year to keep shifting smooth and free. If the cable/cable housing are old and worn they could be offering resistance.  If that resistance is too high the springs in the derailleur may not be strong enough to pull the cable through.

Try removing the cable and housing, then make sure the derailleur and shifter are moving freely before fitting the new cable.

Then replace the cable and housing (these are cheap to buy online, but you do need a pair of housing cutters to cut the cable housing - think mine cost be about £15).


I want to provide an initial answer to this question with some resources that I have discovered and attempted.

Sheldon Brown's Chainring Centering Guide
Velowood Cyclery's Chainring Centering Guide (Updated)

Basic Strategy:

Loosen the chainring bolts until they are finger-tight
Rotate the chain until you reach the tightest section of the chain
Strike the top of the chain lightly with a rubber mallet until you have loosened this tight section.
Continue to rotate and strike any tighter sections that you encounter, gradually softening your blows on subsequent strikes.
Once your chainring is centered and no more tight spots are observed you can tighten the chainring bolts in a star pattern.

Troubleshooting:

If after several attempts you can't loosen a tight section there are two things you can check:

Check for a bent chainring / crank, or off-center bottom bracket (suggestions on how to do this?)
Check for an unevenly worn or stretched chain

Use a chain wear tool and measure the chain wear along the entire length of chain.  Lay the chain down on a piece of paper and write down the wear measurements for each area, then crossmatch those measurements with the tight spot.


Hollowtech 2 cranks and bb how good they are?

They are easier to install and maintain, and depending can be lighter.  However, it's not likely that you will notice any great difference in efficiency commuting on them.  Probably not even 10% of the difference you would notice in a tire change (assuming the old bottom bracket and cranks were in good working order).


Which upgrades are required for participate in cycle race?

You can ride any bike in a race, provided it's in good enough working order to get you over the line.

Regarding gears, it looks like the cost to add derailleur style gears may be prohibitive, as I assume this bike's rear wheel is single-speed specific and the dropouts aren't vertical (which isn't the end of the world but not ideal). I'd probably either look at a geared road bike, or rebuild your rear wheel around an Alfine/Nexus internally geared hub.

If this is your first race I'd probably just ride what you have to see if you like riding competitively before spending money on upgrades or on a new bike.

edit: This 'race' appears to be a 200km audax - I'd be incredibly reluctant to do that kind of distance as your first race. Have you ridden over 150km in one hit? If you're super fit, or not bothered about your time you could do it on your existing bike, but a specific road/audax bike would do it quicker and more comfortably. Maybe build up slowly to that kind of distance - that's a very long day in the saddle.


Full carbon fiber 29er suspension mountain bike from AliBaba

Ask yourself this- would you buy a car off of Alibaba to save a few bucks, or would you fork over a little more money and buy a Honda/Toyota/whatever?

Buy the name brand bike. If your Alibaba bike's headtube snaps off on a gnarly high speed descent, who's going to do something about it? Not Alibaba, and good luck getting the manufacturer from god knows where to do anything about the catastrophic failure of their no-name bike.

Buying the bike pictured is a total gamble, not just in terms of your money, but in terms of your safety as well. Play it safe, pay a little more, and stick with the Giant- they've got a great reputation, they make great bikes, and they back them up.

Alibaba is for widgets. A bike is not a widget.


Its a Chain tool, the long bit should screw into the back (bottom side in the pic) of the other bit to provide a handle. You can then put an hex key into the twisty bit at the right hand end.


That depends on the tyre, the range of pressures is printed on the sidewall of your tyres. It's your choice what pressure you want - lower pressure is generally more grippy and less bumpy on rough roads, high pressure saves energy. If the road is smooth, go for the upper limit of what is printed on your tyre.


A normal clincher tyre will have a "bead" as shown in the following diagram.

It's possible you have a "tubalar clincher" like this:

If none of those quite look right, could you provide a photo?


Hub shells with pressed flanges, as opposed to being one solid piece, can do things like this. In such a case the press fit wasn't tight/solid enough to resist all the considerable forces on the shell, and it gradually came loose.

The bearing cups that most hubs have pressed into them can also come loose and cause a similar set of issues to what you describe.

Both are rare problems, although it's probably true that most or many pressed flange hubs can self-destruct like this if ridden hard or long enough.

If it's not one of the above, then I have no idea, other than maybe something went wrong with the machining and it didn't have proper wall thickness or something. But this would be a very weird failure from a one-piece hub shell.

Getting a new wheel is the only reasonable fix.


Is a Shimano Dura-Ace 7800 rear derailleur compatible with a Dura-Ace 7900 11-27 cassette?

The RD-7800 manual states that the largest sprocket for a SS is 27T.

Manual here https://static.bike-components.de/cache/dl-rd-7800-2-pdf-ce95c6782564d2bbf75cca831ae0bcbf.pdf


I have a 12 tooth jump on my granny gear from 30 to 42 and don't have any shifting problems using Shimano 2300 level equipment. A standard compact crank is 34/50 which is a 16 tooth jump, so 12 teeth really shouldn't create a lot of problems.


Chain too wide for gap between chainring and chainring guard

the Giant site it says that this is sold with a KMC Z51 1/2" * 3/32" chain.

So it should have a 3/32" chain.

  I've since gone to two different shops who have both sold what appears to be the same sized chain (1/2" * 1/8")

1/8" = 4/32". That's more than 3/32".

  which isn't fitting, as it's too wide.

Funny that.

1/8" chain isn't stronger unless you spend a lot of money on a high-spec track chain, which would have a more complex construction inside the rollers.

Get a 3/32" chain.


Saracen Tenet 2 suitable for long distance

The bike should be perfectly fine for 100 mile ride, specs look similar to other products in this price range. I'd rather bother myself with fit and comfort, these will mean more on long distance ride, ask LBS for a test ride.

  doesnt have disc brakes, is this a big deal?

If you are not going to descend mountains or ride in very wet conditions, then no. People are riding without disc brakes for years, it's just another option.

  sora gears set seem to be well reviewed

Sora should do the shifting alright.

  carbon fork keeps this bike light?

Not exactly, aluminium forks are about 200 grams heavier than carbon fiber, which isn't big deal, given the bike weight almost 10kg. It should be somewhat more comfortable, though.


Is it possible to reverse cable direction in Shimano M770 shifter?

You should switch your derailleur out for one with a reverse pull, but there is absolutely no chance that you'll get the shifter to reverse the operation of the cable.


I found this frame at a garage sale, and wanted to know if it was a GT frame if so what kind? The serial number I found on the bottom is GB06070827?

It's virtually certainly some kind of department store BMX. The welded-on pants-guard attachment points, the battleaxe-like dropouts (which did have their era on actual BMX bikes, but most of that time also overlapped with the ubiquity of 14mm axles), kickstand plate, and the threaded 1" steerer combine to point pretty decidedly in that direction.


Freewheel to cassette Conversion 2016 Windsor Wellington 2.0

Wheels with free hub bodies for 8 to 10 speed cassettes can accommodate a 7 speed cassette with a readily available spacer.

Your bike almost certainly has standard road bike 130mm dropout spacing, but it’s a good idea to check before purchasing s new wheel.

Derailleur should work fine, will probably need limits reset and indexing adjusting.

It’s a good idea to get a new chain with a new cassette. A worn chain will accelerate wear on a cassette.


I can't see how a flat inside ring with no pick-up points machined
  into it wouldn't be compatible, providing the bolt patterns match up
  (which they do, I think).

The bolt patterns are compatible.

There are two reasons why the chainrings still may be counted as non-compatible:

Not all Shimano chainsets have identical fitting of the chainring, even if the bolt circle diameter is the same. Sometimes a chainring has to be slightly filed on the internal diameter. I tend to think that this clearly intentional incompatibility is not introduced without a reason and there is some other subtle difference.

In practice: I used some "force-filed" chainrings and do not remember noticing poor shifting.
28T chainring will not be "hyperglide-compatible" with your larger chainring, whatever size it is. The latter is designed especially for upshifting from the 22T. Being shifted up from the (rightly positioned) 22T, the chain links hit the shifting pins and dents so that the chain engages properly. Being upshifted from another chainring, the chain links would not be correctly positioned (except if by luck).

This is the reason why, for example, the Shimano PDF which you linked lists two different 38T chainrings: "38T-AM" and "38T-AK". The former is "hyperglide-compatible" with 24T-AM, the latter with 26T-AK.

In practice: Some people would say that the difference is again not noticeable; here I disagree. IMO the front shifting degrades seriously.


Spokes both too long and too short on same side of wheel

It turned out that the problem here was grossly over long spokes. I'd managed to miscalculate so they were 4mm overlong.

It appears that this allows the hub to move further than it should so that some spokes cannot reach while others protrude past the rim.

Although mislacing the wheel may cause the same symptoms this was not the cause in this case.


Fundamental principles of tire friction for off-road biking

So let me get this straight before it becomes a mess:

  ..increased downward force from pedalling..

When you pedal the downward force is not increased - you are not getting any heavier. You can only increase the downward force on a rear wheel by shifting your body back - this will decrease the downward force on front wheel though, which is good for steering actually. Controlling your body position is easier and more precise when not pedalling.

Cars actually act differently while cornering than bikes - bikes lean into the corner. But for the tires and traction that part is the same and you are right.

Maximum cornering angle is proportional to the coefficient of friction of the tires to the gravel/road/whatever (this is only affected by the tire tread and tire compound). The faster you want to go in corner the more you need to lean-in with you center of gravity. So if you manage to throw your body off seat closer to the ground the tires won't have to lean that much - see the picture - giving you a better cornering grip.

So the correct way is: Pedal before the corner to get your speed, then off the seat and control the centre of gravity for maximum cornering grip (you are not able to pedal now), keep weight on both wheels equally for steering, focus on hitting the corner apex (this is actually the most important part), then pedal again off the corner.

With bikes and cornering also the width of the rim plays a role. If running lower pressure to get more grip (bigger contact surface for the treads to bite into ground) with narrower rims you can get a tire blowout (when tubeless) or lose balance as the tire sidewalls have less support. Wider rims provide better support for cornering (but wider are also heavier giving less acceleration).

TL:DR: your logic is correct, tire tread veeery important, pedaling is BS, use your body weight to your advantage, lower pressure, wider rims.


It's a Tektro RL340, or the same lever under another name. Cane Creek SCR-5 hoods are the readily obtainable option. Tektro made variants of this lever for a bunch of brands, including their own, but the Cane Creek hoods work for all.


Bicycle spokes poking through rim, what can I do?

Well, the easiest would be to trim off the excess of the spoke, preferably with the spoke not in the rim during this process. Or, more preferably, replace the spoke with the one of correct length.
However if you tend to keep the current spoke it may occur that due to incorrect length it does not have enough thread for the nipple to provide proper tension adjustment.

What is more important here is why is this spoke protruding the nipple? Is it of incorrect length? Is the rim not true? Is the lacing wrong?

Could you, perhaps, post a picture showing how this wheel is laced?


As was mentioned in the comments, this question will depend on what derailleur you are using both front and rear (since they have a rated capacity). Too large a difference and the front derailleur will not shift well, but you also have to make sure the the total difference between large-large and small-small is within the range of the rear derailleur so that it takes up the slack and does not overextend. The specifications for your derailleur should have these numbers listed and then you can pick an appropriate sized ring to fit your crank from there.


Can anyone identify this freewheel type?

Clarification - I count 24 slots for a 24 spline removal tool, and not 25 as you state.

Jumping off from there I suspect you may have a Normandy/Maillard freewheel which takes a Bicycle Research Tools CT-3 24 spline freewheel removal tool.

Link to tool: http://www.bicycletool.com/normandymaillardfreewheeltool.aspx

Here's a link to the Bikeforums thread that lead me to the above link to the biketools website: http://www.bikeforums.net/classic-vintage/604233-freewheel-removal-tool-older-simplex-design.html


Front wheel shudder on Cyclocross brakes

The stutter comes from the way the brakes are actuated. From the picture on Javelin's site I see that the housing is held at the top of the head-tube. When you brake the fork flexes backwards causing the cable's tension to change. The brakes will be slightly released causing to fork to move again, re-tightening the brakes, pushing the fork backwards. This happens in quick succession thus the brake stutter. The way to cure it is to move the attachment of the cable-housing to the crown of the fork. There are front cable hangers that can be screwed to the hole where a side-pull brake would be attached.
Google for 'Front Cable Hanger Fork Mount'


Generally you can use any stem and bar you like, as long as they have the correct clamping diameters.

Be aware that you might need longer or shorter brake and shifter cables.

As a sidenote: I think often when people have the impression that there is too much weight on their hands it’s actually because their saddles are too low or in the wrong position. With a proper seating position roughly a third of your weight is on your hands, butt and feet each. With more intense riding it can be more than half your weight on your feet (this is one of the reasons why pro riders can ride such low bars and hard saddles).


Can I replace my self-energizing brakes with regular cantilevers?

The Scott-Peterson SE brakes used standard canti bosses. You're probably safe to replace them with standard cantis or V-brakes (what type of levers are you using?).


How many spokes for a single speed road bike?

If you have the same number of spokes front and rear, either the front wheel is heavier than it needs to be, or the rear wheel is weaker than it should be.

In general, that's still true.

The rear wheel generally is subjected to much greater stresses than the front wheel - the rear wheel normally supports about 60% of the combined weight of the rider/bicycle combination along with all of the power transmission.

The only time a front wheel is normally subject to greater stresses than the rear wheel is under braking, where the front wheel takes most of the stress.  But braking is normally a fairly smooth force that is less stressful than bearing weight over bumps or the peak stresses of transmitting power from the pedals to the road.  And for rim brakes at least, the stress on the wheel is a lot less as there's no torque on the hub and spokes like there is on the rear wheel, where power is transmitted from the chain to the road via torque through the hub and spokes.

Note that was likely written before disk brakes.  Disk brakes change things because the braking force has to be transmitted through the hub and spokes to the rim.  So you don't want to to have a 32-spoke 3-cross rear wheel with a 20 or 24-spoke radially-laced front disk brake wheel (pretty much a normal configuration for my rim-brake road bike 32/3x rear, 20-24/radial front).

But I suspect with a front disk brake, a 32-spoke 3-cross rear paired with a 28-spoke 2-cross front would be fine.

Overall, though, having a few extra spokes on the front wheel isn't going to matter much.  If I could save $50 or more by buying an off-the-shelf 32/32 over a custom-built 32/24, I'd personally use the money on something more useful than a few less ounces of spokes.


Reading the comments I am going to presume the problem lies with the rim/pad interface not generating enough friction rather than pressure from the brake lever getting to the pad/rim interface.

First step - Presume the rim is contaminated with something slippery. Clean the rim presuming its either oil or silicon based. Use an degreaser/solvent first to attack an oil based contamination, the use an abrasive cleaner and scrub well with a steel wool or aggregative nylon scrubber and plenty of soapy water to remove non-oil based contaminants. Don't worry too much about damaging the rim - if you can't get the brakes working do you want you son riding on it?

Now the pads - presume these, even if new, have been contaminated by the rims. Ideally buy new ones (Come to that later), second best and worth a try is to clean them with degreaser, soapy water then file or sand the top layer off.

Assemble them with a bit of toe in (front of pad hits rim first). Put them together. (Look here for good instructions). Now the brakes need to bed in. Go for a ride, and give them a dozen of so max effort stops from high speed (careful you don't do anything silly)

Couple of points: Are the pads good quality one like Koolstop?  Cheap pads are often made of hard compound, take a long time to bed in and have low friction.  If possible, get softer pads with more grip (and shorter life). The brakes are calliper brakes typical of road bikes, that offer poorer braking compared to V brakes and discs. Better callipers may help, but they do have a limit of how good they can get.


How do I maintain a Brooks leather saddle?

Brooks makes a product called Proofide for saddle care.  For normal use, once or twice a year is likely enough.

To use, start with a dry saddle and wipe off any grit or dirt with a dry rag.  Then take a very small dab of Proofide and spread it on the top surface of the saddle.  You want to spread this out into a very fine layer all over the top (finished) side, don't use too much.  Then let it dry -- probably takes 4-12 hours, depending on how much Proofide you used.  Finally, polish the saddle to get rid of any excess Proofide (looks like a white waxy residue).

There's a Brooks maintenance kit that includes a tin of Proofide, a polishing cloth and a tension adjustment wrench.

Also, try to keep your saddle as dry as possible.  Riding in the rain is ok, but make sure you store your bike somewhere that the leather can dry out naturally.


How do I tell if my cog needs replacing?

The sprockets (apart from the 13 tooth) are reversible, so you can get twice the life out of one by taking it off and using the other side of the teeth. From the photo it looks to me as if it's only worn in one direction so far, or at least significantly more worn in one direction.
http://www.rohloff.de/en/products/speedhub/sprocket/index.html

(From my experience with a 3 speed hub, a hub gear sprocket can be badly hooked without causing problems when run with an equally worn chain, long after the point where a derailleur wouldn't shift properly. I'm not recommending that you let it get that worn though.)


Stopping interference between LED lights and wireless cycling computer

Because the items are going to have to remain in close proximity, it's unlikely that there is anything that will completely solve your problem, but there are a couple of things you can try.

If the lights are wired, it is possible that the wire is working as an antenna, and you can use a Ferrite Choke or two on the wire.

Tape one near where the wire leaves the battery, and another to where the wire lead plugs into the light.  The can be found at stores like RadioShack for a few bucks.

If the lights are wireless, aluminum and tin foil is an excellent reflector for this kind of Electro-Magnetic Interference (EMI).

The first step would be to see if foil will help.  Try wrapping the outside of the lights with foil and repeating the tests you did before.  I doubt you can add foil to the computer because this will interfere with it picking up the wireless signal from the sensors.

If that reduces the interference you can tape the foil to the lights, carefully cutting away the foil around mounting brackets and buttons and see if the EMI is still reduced.  If the lights can be easily disassembled you can try taking them apart and lining the interior with foil as well; take care not to short out the internal electronics.

Good Luck.


I used nail varnish, it sticks well to the plastic and is very tough. It's easier to apply than spray paint,  but a bit more fiddly and forms a thicker layer of paint. I also used it to mark the locks. You get bottles in the most absurd colours in a 1-pound shop in the teenage cosmetics section.


Can I use BMX brakes on my Murray Ultraterrain MTB?

The features that need to match are reach from mounting bolt to rim and recessed / normal nut. A BMX sidepull brake will probably work, but it's better to check the measurements before buying.

For younger readers, Murray was a legendary BSO brand in the 1990s. They did come with centerpull brakes made out of thin sheet metal.


There's also The Sufferfest.  I haven't tried these out yet as I need to get up the courage to try out my new rollers.


What is a modern equivalent to "fir el 201" rims

According to BikePedia, these did not come stock on the Bianchi Eros in either 1996 or 1997. Since this bike came stock with Mirage level components, you're probably looking at a low - mid level quality OEM rim. Fir is/was a good brand, as is Ambrosio (which came stock on this bike). Finding a rim from Velocity or Alex Rims or Mavic just to name a few common manufacturers will provide you with a quality alternative that is affordable and readily available today.

To match the style, you are going to want to get a low profile or "box" style rim as opposed to a deep profile or "aero" rim. All of these companies and more have a style of rim like this.

You will definitely need to purchase new spokes and nipples for this, so make sure you know how to purchase the proper size.


There are off-the-shelf products satisfying your needs at sub €2 price tag
:

This one is actually an adapter for stem tube but I don't see a reason that it shouldn't be used as stem quill adapter. Which means you simply manufactured this part yourself, even using the same material (the one depicted is aluminium).

Coming back to your initial question - since you've also put a length-wise cut on your adapter, the inner diameter varies within some range - it needs to be slightly larger to be able to slide it on the steerer tube. Of course, when clamped, the inner diameter is exactly what it needs to be. So in my opinion, yes, it is correct to make a reducer the way you made it.


At 200km you should be able to take the bike to where you bought it for a free tune-up to adjust brakes and derailleur indexing etc.

Ask to have the front hub looked at as it definitely should not be making noise and will be covered under the warrantee. The problem might be fixed by lubricating the area around the rubber gasket, but you want to make sure there is not a problem with the bearings.


How to stop bike renters overextending seatposts?

I assume they are extending the seat post that far because they need it for an appropriate saddle height.
So the solution is simple: Offer bikes with larger frame sizes or at the very least equip the bikes with long seatposts which can be extended far enough.
Any other solution would force your customers to ride with a too low saddle.
If you still want to make sure that they can’t be extended too far, just in case a giant with long legs comes along, there is a solution I can think of: If you have seatposts where you can see through the tube (common on cheap steel seatposts) you could try to attach a string (or steel cable) somewhere at the bottom bracket, thread it through the seat tube and seatpost and tie it to the saddle rails. Could lead to some noise though if the cable rattles inside the seat tube.


Any tips on riding a roll-off, followed by a trench?

When I come across something like that, instead of riding straight down the hill I will head down across the hill on a diagonal. You can carry more speed this way and you won't hit the far wall of the trench and risk being sent over the bars, when your bike comes to an immediate stop.

This goes for any type of bike, rigid or full suspension.

If the risk of crashing in the ditch is low, I'll go straight down the hill while managing my speed. When at the bottom, simply lift the front end enough to clear the far side of the trench. This of course requires quite a bit of effort and/or skill depending on the surface of the ground, the slope you are descending the size of the trench.

Alternatively, get enough speed and jump the entire thing.


They probably weren't talking about the cranks per-se, but the whole crankset, which is the cranks and the chainrings.

Compacts are cranksets with smaller chainrings (typically 50 teeth and 34 teeth) as opposed to standard cranksets which have say 52:42. Combined with wide-range cassette this can give a good range of gears without having to have a triple-ring.

Biopace were oval rings - you can get non-round chainrings for either compact or regular cranksets.

Note that the cranks themselves do come in different lengths to account for different leg-lengths, but this is independent of the chainring diameter.


The pads are positioned reasonably close to the rim so the brakes are probably be adjusted correctly. The does not appear to be rubbing on the pads. It will most likely not be a problem.

Whether this is acceptable on a new bike depends on the quality and cost of the bike. Most bicycle purchases come with a free tune-up after a short period of time, and a good bike store should deal with minor issues for no cost. Have the store take a look at it.


Why is my front crank clicking/creaking?

Look at the front shifter metal cage. Is the chain touching it? It is the most likely problem. It may be more apparent with certain gears  in the rear than with others.

If yes, shift to the middle in the back. Try to turn the barrel adjuster on your left shifter one way and back. Does the noise change? It should and you should be able to find a position where it does not rub.

After doing that you may need to adjust the limit screws for the inner and the outer chainring.


Annual technology gap of high end road bikes

While not disagreeing with the first answer above I think there are a few more complexities that haven't been addressed.

Changes in bike technology are not linear but rather generational. Component improvements don't happen each year but rather every 3-4 years. Aside from pro and sponsored riders most riders would not see any value in replacing a bike for the next years model and the industry recognises this. Better to sell a new frame together with other new tech as it's released so people actually are getting something new.

Di2 was first used in the Tour in 2009 and it became commercially available in the same year. In 2011 it was released on Ultegra, which marked the first trickle down. In the last 3 years it has still not been released on 105. Until they are released in 105 it won't be available on mid range bikes and they will sit in the $2,000-$3,000 price range. That change should be due in the next year or two, unless for other commercial reasons Shimano sweat the Ultegra Di2 line and the new 11 speed 105 line for a few more years. 1 year after releasing 11 speed 6800 they released the 6870 Di2 version for Ultegra. They released 105 5800 in 2014.

It's worth noting that in electronic shifting they have no real competition from SRAM or Campi's EPS (as opposed to  mtb where after Shimano released shadow+ SRAM quickly followed and released type 2 and then 1x11) so will continue to milk their mid range Ultegra until they see sales of that dwindling.

Electric gears will never be standard because there is a cost/ weight/ don't care ratio to consider. There's a point where most people won't be willing to pay (or maintain) an electric shifting system.


Q: "[W]ould a competent welder be able to fix that crack[?]"

No, that frame is done for. By attempting to weld such a crack, a welder would prove their incompetence.

Even if you fix that crack you might find another crack on the right hand side, mirroring this crack. What is more, the crack will go considerably deeper.

I had a crack at the same spot and we asked the manufacturer (Corratec). According to their frame builder welding would warp the head tube too much to seat the head set properly.

Q: "[Why] can a crack develop at that point[?]"

Aluminium is susceptible to fatigue under light dynamic loads.

The upper bearing of the headset is pressed into the headtube at this point.

The position of the crack suggests it is caused by a force pushing the upper bearing forward. Due to the great mechanical advantage of the fork/headset system forces pushing the wheel backward require the upper support to bear a force pointing forward. This strains the upper support. (The lower support is compressed).

When you pull a ring from the inside it will typically break at the same points your tube cracked. (If I remember correctly from undergrad engineering ±2/3π from the direction of the force.) (Try it for example with a bagel.)

If your headtube showed cracks at any other place it would suggest machining tolerances not met. A head tube that is too tight cracks when the upper bearing race is pressed in. These cracks would then grow, for example, due to stress corrosion cracking.

Q: New frame?

Have you tried to ask Ghost? Corratec have given me a new frame when their ten year old frame failed in the same mode.

PS: Do not ride your cracked bike! Not even a single metre: it might fail catastrophically without warning.


Why are bicycles considered vehicles and not "walking aid"?

a cyclist has the speed, mass and maneuverability of a sprinting person

Not really! The world record for 100 m sprint is 9.58 s, which equals 37.6 km/h, which is fast but not anything spectacular for a bicycle. The marathon world record equals to little more than 20 km/h, which is less than my average commuting speed. Going back to "human" speeds, I would estimate that an average biker goes roughly twice the speed of an average runner.

With double speed:

Braking distance is quadrupled (ignoring reaction time).
Kinetic energy = damage in case is collision is quadrupled (not even taking into account 10-20 kg extra mass & hard and sharp metal parts of the bike).


Ultegra 9-speed brifter upshift problem - beyond WD-40?

This link may be useful to you if you really want to dig around inside your shifter; though it looks like it might require a few special Shimano tools. Also note that he only has full strip/rebuild info for Dura-Ace...though I would expect Ultegra to be substantially the same, differing mainly in the use of plastic instead of metal for some parts.

Also consider that it is pretty easy to find Ultegra 9 stuff on eBay and elsewhere, and it may be more time-efficient to just replace rather than repair.


The two clicks are just one shift. You can do a half shift from the big ring to the small ring by pressing the downshift paddle about halfway. This is to keep the chain from rubbing when you are in a low gear in the back and the big gear in the front. This half shift is known as "trim". So two clicks up for a full shift into the big ring, two clicks down for a full shift into the small ring, one click down to trim the derailleur away from the chain when you're using gear extremes (big-big).


Aluminum fork: paint defect or sign of strained?

I think that's a paint defect.
Aluminum would not stretch enough to flake the paint off like that without staying deformed or actually cracking.
If the fork or wheel had suffered a collision into a solid object that had bent the fork, you'd see evidence in the paint on both the front and back edges.


what could be the reason for very inacurate strava tracks of my bike excursions?

GPS units have variable performance for a number of reasons

Bad satellite position - Simply put, all the satellites transmit "bing!" at exactly the same time.  Your received deals with the differences in the time between reception of each signal.  So the most accurate point will be calculated if the satellites are distributed over the sky.  If all the visible satellites are in the same quarter of the sky, you get a larger possible location, or one with more possible variance.
Urban Valley, regular valley and multipath - if you're in an area with big hills, or tall buildings, or sometimes even very wet trees the signal can be attenuated, slowed, or reflected.  If the signal is slowed by even 0.001% then that's 22 kilometres of variance, (assuming satellite orbits at 22,000 km.  This can be mitigated somewhat by putting your phone in a toptube bag rather than deep in your pocket.

I carry a folded thermal space blanket made of foil when on long rides, and it messes with the phone terribly if they're in the same pocket.  Doesn't matter which is on top.  Also if your clothing has a metallic weave this can interfere with transmission reception too.

Fudge factor - Some GPS, and the Strava app are known for "slewing" results.  They've used the last N seconds as an input to calculate the next point.

Here's an example.  Notice entering on the left at fairly decent speed, probably high 30 km/h.  The path slews out into the river, and then winds its way back to the road.   I have seen far worse at this corner but this was all I could find in a brief search.  I do this segment frequently.

Broken antenna/aerial(s)  Your GPS is on a bike and suffers a lot of vibration.  If the signal is not received clearly then that could add delays which impact processing, or could drop one/some of the time pulses from the satellites increasing error
Lagged CPU.  Historically a GPS was a standalone device with dedicated chips for calculating everything.  If you're using a smartphone, there will be dedicated GPU circuitry but it will still need time on the main CPU to do stuff.  If its busy playing songs and whatever else, then that could also delay the processing of point data.
Your speed - If you're going fast enough, minor discrepancies can multiply out to larger errors.   50 km/h is almost 14 metres per second, so a second's lag puts you out by 14 metres.

I'm not familiar with Garmins, but they're single purpose units and are unlikely to suffer CPU starvation. (other than garmin's rear-facing radar whatsits.)

That's all the causes I can think up now.

Solutions

The best solution is to tweak your strava recording using SNAP (strava needs a polish)   However I've noticed this site has become increasingly harder to get to.

When it does work, you can load your activity from strava, push the lines back onto the road, and it will create you a GPX file to download.

Then you upload that fixed file to strava and once its looking better you can delete the original ride.  Do it in that order for safety, I've lost one big ride by getting it wrong.

Second option is to use your garmin to to the logging and leave the cellphone recording as a backup, deleting the worst once once you return home.


Cosmos is a South African manufacturer. I believe they hand built good quality road and track frames but have long been out of business. You will probably find an enthusiast to tell you more on http://bikehub.co.za/  Nice bike!


microSHIFT on front gears, how does it work?

Microshift is a brand. They are Taiwan base.

Most of the twist shifter operates in similar manner as you described. They are for trimming as Batman said. But in fact it is made from the same machine and parts to keep the cost down.

It is all about how to set up the front derailleur in your system, and find a spot for each appropriate gearing. i.e. avoid chain rubbing on the front derailleur

There is one thing that I like about twist shifter, is that when you shift up, you can go slightly higher than where it suppose to be on the front chainring. This helps your chain to shift up easier and faster.


Can I use a smaller bike inner tube than it supposed to

That's not going to work, you need an inner tube of the proper size for your wheel rim diameter and tire width.

The tire width should be printed on the tire along with the diameter. Tubes come in various width sizes that support a range of tire widths.

If in doubt, take the bike or wheel to the bike shop and let the staff pick a compatible tube for you.


Are pedal washers necessary on a carbon crankset?

If the instructions that come with the pedals tell you to use the washers with carbon cranks then you should do it. The reason for the washers is that that they keep the axle from rubbing against the crank and thus damaging the carbon when tightening the pedals.Oh yes, and you can compensate the thickness of the washers by moving each cleat 0.5mm outside.


Installing downtube shifters on a bike with no bosses or cable stops

For downtube shifters, I prefer to run as little housing as possible.  Your best bet is to look for some new old stock (NOS) vintage parts.  You need two bits: a chainstay-clamping housing stop for the short housing loop to the rear derailleur, and a downtube-clamping cable guide for making the cable bend at the bottom bracket up towards the front derailleur and back towards the rear derailleur along the chainstay.

A quick search of eBay shows both available pretty readily. Several manufacturers make the chainstay clamp, but the Campagnolo 636 is representative.  The best downtube clamp for both a front and rear derailleur looks to be the Campagnolo 626/A double guide, though Huret, Suntour and a few others also made them.


Looking for ideas on how to track bike wheel rotations or distance traveled

Two main technologies picking bicycle speed are magnetic sensors and pickups counting wheel revolutions and ANT+/Bluetooth sensors with accelerometers  counting wheel revolutions.

Magnetic sensor into a micro controller would be trivial and is not really a bicycle question. ANT+ sensors follow a standardized API so you could look for a micro that support ANT+ and look at the ANT+ API for bicycle sensors.

Not sure how the accelerometers go on stationary bikes as they auto calibrate distance/revolutions, and a stationary bike has 0 distance.

I will ignore GPS...


Is it really necessary to physically cross (interlace) the spokes on traditional wheel lacing?

Probably the best source for answering this is Jobst Brandt's The Bicycle Wheel, the definitive text on the wire-spoked wheel and an essential for anyone interested in the art of wheelbuilding.  Excerpted from page 68 of the 3rd edition:

  Spokes in a crossed pattern are usually interlaced at their last crossing before reaching the rim. Spokes coming from between the flanges are laid over those from outside the flanges. Interlaced spokes take up each other's slack during severe radial loading and reduce the chance of spokes becoming loose. If spokes become loose, their nipples can unscrew. Radial spokes cannot be interlaced and therefore, lose alignment from road shock more easily. Interlacing also gives more clearance between the spokes and the derailleur on rear wheels.


Making a very sharp turn by pivoting on your front wheel?

In german this is called "Hinterrad versetzen" -- "displacing the back wheel". I got to learn this in an mtb course I took a while back. If you can, try to find an instructor or other experienced rider to teach you.

How to practice:

Start very, very small and always wear full protective gear, i.e. a full-face helmet and vest in case you crash. You will crash. Be prepared. Have a friend with you just in case.

Look for an open, empty and even space like a parking lot or similar where you can brake without fear of slipping. If possible, avoid concrete or similar very hard surfaces.

First, you practice the stoppie, without turning. Start small, i.e. just lift your back wheel a couple of centimetres. You don't need to ride very fast, it's mostly about the balance on the bike. It's absolutely possible to do this from a walking pace. Instead of moving your weight far back, as you normally would in a hard stop, keep it (more or less) in front. Find the point where it's easy to lift the back wheel without getting the feeling you will crash any moment. Do this a couple of times. Slowly increase the height of the back wheel.

Do only the stoppie until you feel comfortable "standing on your front wheel" for a second or two without losing control.

If you feel safe holding the stoppie, try pushing your back wheel around a couple of centimetres by letting the inertia turn the bike. You need only provide the tiniest motion yourself, physics will do the rest. Slowly increase the arc until you are where you want to be.

Note 1. If you have front suspension, beware of your fork kicking back when in the stoppie. This can easily overturn you.

Note 2. I wouldn't try this on stairs or a rocky or otherwise dangerous path until I was absolutely sure I can do it. Also, don't force it. Practicing this kind of thing takes time and drains you faster than you think. Try integrating training into normal rides instead of riding out just to train.


First, it may not be your bottom bracket.  Creaks and clunks are notoriously difficult to localize.  If you can reproduce it with the bike on a stand (or upside down on the ground), it may be easier to know for sure.

If it is your bottom bracket, you should replace it (or less commonly, replace only its bearings, depending on the type of bottom bracket).

If you continue to ride, eventually it will probably get worse, but this won't harm anything other than the bottom bracket, so it's not particularly urgent.


I've had the same mixed results using the Edge 500 for courses.

It sounds like you used a TCX file for the first course, giving you a better auto-zoom level and accuracy, and maybe a GPX file on the second course, resulting in less accurate performance. Sometimes though, it seems the little 500 just doesn't have the accuracy of other models and strays off course.

To adjust the zoom level, page over to the map/course layout and press the power/light button. You'll see the zoom level is probably set to auto. Just use the up/down arrows to adjust the zoom level and hit enter when you're done.

Generating TCX files with ridewithgps.com seems to be the most popular way to chart a course and add cues and turns. Most popular routes already exist if you search for them.

For what it's worth, the newer models, 510, 520, 1000, etc, seem to have a much better grasp on your location ( and liekly extra processing power to help ) and throw up an off-course false alarm much less often, even under dense tree cover.


There isn't all that much point.

We have a lot of knowledge on how to make steel tough. It's also pretty cheap. This basically makes it win-win for manufacturers: use enough tough steel in a good structure with a good locking mechanism to get a decent lock. It doesn't cost a lot and its easy to fabricate.

The weight of many good locks is not that much to begin with; the main design goals with a U-lock is to leave as little space as possible to get a jack in, hard enough to cut, and has a proper lock mechanism. So, locks like the Kryptonite Evo Mini line are very good for many locking jobs and don't weigh all that much (about 1.5 lbs for the Mini 6). So, there's not all that much point in reducing weight.

There are some locks which are not steel -- Tigr makes titanium locks, for example. But they're less well known and twice the price of a high quality steel lock, such the well tested Kryptonite New York Lock line. And the smaller units don't necessarily hold up.


I have read an article regarding partial fairings for upright bikes.

It is interesting that a partial fairing will reduce the energy needed to keep the bike rolling at 35km/h while in a fairly relaxed riding position by about 1/4 (220 watts to about 160 watts)!! (Data sourced to David Gordon Wilson, Bicycling Science, 3rd ed., p.188).

So the heck with the speed or rain rationalizations: if you want to travel farther and conserve energy in the process (a.k.a. touring), a partial fairing should definitely be considered!


Should I remove the chain before installing new rear derailleur?

It's much better to open the chain. Derailleurs are not really designed to be opened repeatedly, and doing so inexpertly can potentially ruin the derailleur. Chains might have either a lock link or a master link of some kind, find that open the chain and then thread the chain through the derailleur. If the chain does not have one of these links, you will need a chain tool to split the chain. DIY grade ones are quite cheap and do the job well, but you will need to read up on how to use it properly.

Also consider that if the size of the derailleur arm is different, your chain may need either fewer links or more links to fit properly.


Not out of the box. Shimano road and MTB shifters pull a different amount of cable with each shift. Art’s Cyclery documented that Shimano 11s road shifters pull 2.7mm, and Shimano 11 MTB shifters pull 3.6mm. Thus, an 11s MTB rear derailleur will never shift correctly.
I have not used this particular cable pull adapter by Jtek engineering, but it claims to change the cable pull so that Shimano 11s road shifters can shift MTB derailleurs, and vice versa. This might be an option if you absolutely need to do this.


How to properly clean and lube the bearings on a sram apex bottom bracket (GXP)?

SRAM GXP bottom brackets can be user serviced, but it is usually unnecessary.

To service your BB bearings, first remove the crank arms.  Then place your thumb in the BB spindle hole, and bend the joint enough that your knuckle makes firm contact around the entire ring surface of the spindle hole.  Pull outward using fairly firm pressure, and if necessary, rock your thumb side to side.  This will pull free the outer, plastic shield, and expose the inner rubber bearing seals.

Then take a scalpel, or a sharp awl, and use the tip to gently pry up the edge of the bearing seal.  You may need to lift it at more than one area around the edge, but it should pop free with a little force.

Once the seal is removed, clean and degrease the exposed bearings, replace the grease with fresh grease, then replace the seals.  Repeat on the bearing on the opposite side of the BB.

One word of warning: while this is possible, and not likely to cause any issues, it is not intended by the manufacturer, and will not be covered under warranty, should you damage the BB in the process.


What size nipple should I use for granny bike rim?

5.5mm spoke holes sounds ridiculously large and it would not surprise me if that's not correct. Ryde don't mention it on their generic V38 page nor do "Flying Pigeon" on their Westwood listing but they do suggest 2.0mm spokes. No mention of needing large head nipples though.

If you can try the large head in the rim before buying definitely do that. Otherwise I'd be tempted to wait and see, since if you need the large head nipples you'll need to buy them separately anyway so you only lose time by waiting to see if you need them.


'584', '27.5' and '650B' are all the same thing, specified in different wheel size systems.

These size wheels originated in the older French wheel size system and are called 650B (650mm being the diameter of wheel and tire). ETRTO (European Tire and Rim Technical Organization) specifies wheel rim diameters in millimeters (584mm in this case). Mountain bikers call these 27.5" (the approximate diameter of the wheel and a fat MTB tire).

The tire width specifications of your tire and the tube are given in both millimeters and inches. Tube min tire width is 50mm / 2.00", max is 62mm / 2.40"

Your tire width is 57mm / 2.25" so the tube will work with it just fine.


Why does my back wheel keep becoming untrue?

I strongly suspect your spoke tension is quite uneven. If you installed the new spoke by just adding the new spoke, then that's even more likely.

A wheel with uneven tension will do exactly what you describe. There should be only two different spoke tensions in a rear wheel - the tight side and the loose side. Wheelbuilders will keep working a wheel until they get +/- 10% or so. Smaller range on a new wheel, wider on a cheap and/or old one (wheelbuilders rarely build cheap new wheels, those are made by machines). If you don't have a tensiometer (Park tool one, ~$60) you can possibly do it by the pitch of the spokes but I've had little luck with this - it's more affected by where the spokes cross each other than by spoke tension (ymmv, I have perfect pitch and am in other ways fussy, plus I have access to a tensiometer).

The problem with older wheels is often just getting the nipples to move on the spokes. That can take lube and time. Often more time than the cost of a new wheel. But if it's your time, that's "free". Again, use a grease-based chain lube (or for once, WD-40 or similar) on the spoke/nipple junction and also the rim/nipple area. Then work each spoke gently (less than half a turn) until the spoke moves on the nipple. Realistically, gently is an exaggeration - you don't have a lot to lose by breaking the spoke doing this, except that breakage normally happens on marginal wheels (cheap and broken), so you run the risk of breaking enough to make the wheel uneconomic to repair even if you're only paying for new spokes not labour.

I think your best bet now is to make sure as many nipples are free as possible, then take it to a bike shop. It'll cost $30-$100 to fix, but most shops will let you say "spend $X on it, then call me".

At some point the wheel is so warped and unreliable that you just need to buy a new one. I think you're 90% there right now. It depends on how much you're a gambler... you might spend $30 and get the wheel nicely trued and solve your problem. Or you might spend (say) $50, get the call and they say "it's definitely broken now" and you have to buy a new wheel.

If you're short on money another second hand wheel might work, and it'll definitely be cheaper than a new one. Check your local tip shop/ bicycle recycler for cheap ones.

edit: tensiometers are standard bike shop tools, the cheap Park ones work pretty well and are only about $US60 online. The more expensive ones don't work a huge amount better but cost a lot more ($US300+). I've compared a DT Swiss micrometer-based tool to a Park one and no-one in the shop could reliably measure more accurately with the DT one. It was harder to use and heavier so we went back to the cheap one.


Mystery leak from brake caliper. What to do?

Sounds like a bad piston seal to me. Could also be any seal from around the calliper area, split line, cracked calliper.

Assuming these are newish and you've not bashed them up this should be a warranty claim. This will almost always have to go through the place you bought the bike, but there are exceptions.

You should email SRAM, the maker, and the shop to see who wants it back and see if the whole bike needs to be retuned or just the failed brake.


Openstreetmap with the cycle layer certainly shows some. Here's one
I was very grateful for in the French Alps.  OSM is not complete but it's open source so you can improve it (I haven't added any taps, but I have added bike parking).  This is a good approach, as it also shows cafes and shops where you should be able to buy water if there's no tap (flipping between the "standard" and "cycling" layers can show more facilities).
In the UK, the cafes on Cafe Network will almost all be very willing to fill bottles for customers - I normally plan on a cafe stop every few hours and take the opportunity then.  Pubs and coffee shops generally will too. Some chain fast food places won't - they say they can't. This is problematic late at night when nowhere else is open.
A possible fallback in the UK is churchyards - there's generally a tap outside, but no guarantee the pipes aren't lead.
It's possible to query OpenStreetMap for drinking water by modifying the following link to give an appropriate bounding box (the last 4 comma-separated numbers):
https://tools.wmflabs.org/query2map/featurelist.php?key=amenity&value=drinking_water&types=points-areas-infos&BBOX=-2.9914,51.5871,-1.32,50.81
changing value=drinking_water to value=water_point returns some more (e.g. next to canals, for filling boat tanks).
Of course some are on private land.  I've seen campsites and schools showing all their water points.  But that's fairly obvious from zooming in.  The bigger downside is that many are missing.


Park Tool list the BBT9 as the tool to use for both Shimano and FSA external bearing bottom brackets. I would see how tight the wrench fits on your new Shimano bearings. If the fit is as loose as on your FSA I would replace the tool so you don't strip the notches off your new bottom bracket. While the type of wrench with the open side allows tightening the bearing with the crank in place it is more prone to spreading than the type that forms a complete ring around the bearing.


Rear rockshox thru axle. How to remove it if skewer got broken off?

Assuming your axle looked a little like this before the break.

Purchase a new 12mm thru axle of appropriate width for your bike. It is nothing to do with RockShox on the rear axle. Check your bikes spec on the internet or original supplied manuals.

Unscrew the handle from the new axle and use that to undo the splined axle from the original. Once you have done that replace the handle on the new axle and install on the bike.

A couple of issues.

The splines on the original axle might not be the same as the new one unless you get exactly the same brand. If you have access to a LBS this might be the time to use one instead of internet mail order.
Rear axles are sometimes fairly tightly screwed in. Ensure you are careful to not injure yourself or ruin the spline by skidding off the unsecured handle when removing it. Wrap the handle in a rag and apply pressure along the axis of the axle with your palm. Maybe lie the bike flat to do this task. A soft mallet may come in handy to break the initial friction as well.


Are there any manufacturers of steel road bikes today?

Depending on what you consider a "major brand", there really are a lot of nice steel bikes around these days.  If I were going this route, I'd look to some of the brands that focus on the steel frames, rather than complete bikes.  The list below should get you started.  While they aren't the biggest names in the industry, they do have good distribution so you should ask about availability at your local bike shop.  Or order a frame online.  Good luck!

http://www.somafab.com/
http://surlybikes.com/
http://salsacycles.com/
http://gunnarbikes.com/


From Sheldon Brown:

The lever goes on the non-drive side of the bike (i.e. the side without the gears). One spring should be on the non-drive side of the bike and the other spring should be on the drive side. The smaller ends of the springs should be pointing towards each other, towards the center of the skewer.

Since you asked this, I strongly suggest you read the "Installing a quick-release wheel" of Sheldon Brown's page (linked above).


What is a "road" bike? Don't they all ride on a road?

Yes, all bikes could ride on roads. However, a road bike is one that's optimized for riding on smooth pavement. It usually has skinny tires (no wider than 32mm, often much narrower) with a very light tread. (If they have any tread at all. Some road tires, such as the Kojac, are treadless or "bald", to cut down on rolling resistance.) Road bikes usually have handlebars that are designed to be comfortable for long stretches of time, sacrificing a little bit of fine control that you'd get with a wider flat bar or riser bar.

By way of contrast, mountain bikes come with wider tires that have more agressive tread ("knobby" tires) designed to grip gravel or dirt.

Road bikes can sometimes ride on packed dirt or gravel, but the ride will be very harsh. A bike optimized for off-road will be easier to control and can ride on surfaces that'd be problematic on a road bike, such as rocks, gravel, loose dirt, or pockets of sand. There are even bikes that will accept extra-wide tires (3 - 4"). People who ride on very bad roads that have had potholes and cracks installed copiously may prefer a mountain bike to a road bike, or may decide to get a hybrid bike, which is exactly what it sounds like.

In the end, road bikes can sometimes do a little bit of off-roading, and mountain bikes can ride on the pavement, but these kind of bikes have different strengths.


Putting Shimano SORA STI Shifters on Touring Bike with Deore Derailleur

For the rear, a 9 speed Sora brifter will be fine -- 9 speed cable pull is the same between Shimano road and mountain.

For the front, the bike has a Shimano Altus front derailleur. You'll need to swap a road triple front derailleur for that (make sure to check the spec sheet to ensure your crankset's chainring sizes are within spec (not a problem) and the difference between the largest and smallest chainring are within spec (can be a problem) ) -- the bike you have has a tooth difference of 22t for the crankset, which is slightly higher than the 20t that the Sora FD-3403 or FD-3503 is rated for.

There are triple front derailleurs (e.g. Microshift R539) which will have the right front tooth difference though (comes in braze-on and band mounting, depending on the type of mount on your frame).


What type of bicycle parking rack should my company install?

As someone who rides their bike everywhere I have experienced a great many types of bike rack. In my opinion the best choice is a Sheffield Stand.

  Image Copyright David Wright CC BY-SA 2.0
  (http://creativecommons.org/licenses/by-sa/2.0), via Wikimedia Commons

They are cheap, simple and readily available to purchase. When installing them make sure they are far enough apart so that riders have enough room to comfortably part and lock their bike.

b|s|b    b|s|b
i|t|i pe i|t|i
k|a|k rs k|a|k
e|n|e on e|n|e
 |d|      |d|

As others have said, avoid anything that holds the wheels. These provide poor locking options and don't easily accommodate bikes with different sizes of tyre. They can also damage rims and spokes.


Pull the post and hold it next to the seat tube to see how far it goes in.

If it does not go in far enough to be into the seat tube below the top tube you are putting a LOT of stress on the top of the seat tube.

Believe that maximum mark on the seat post.  A seat post is not that expensive to risk damaging a frame.

This is just one (not cheap) seat post but that min mark is pretty conservative.  If you are cheating the min mark you playing with danger.


Do I need to use thread locker or spoke prep when building wheels if spokes come pre-treated?

DT Swiss make a series of spokes called ProLock which incorporate a re-usable thread-lock type feature. You can build these over several days no problem and re-true them for years without trouble. It isn't blue, so that isn't what you have.

The usual blue stuff is Loctite 242 which I would not personally want to use on spokes because it sets in ten minutes and is fully cured after 24 hours; after it cures you can fully break it apart but not make small adjustments, so later truing will not really work. Should you wish to remove it Loctite's data sheet suggests the correct solvent to use is methylene chloride.

I personally use grease on spoke threads, as on any other threads which don't need locking. With grease or ProLock you can take as long as you like. I never tried Spoke Prep for lack of a UK supplier at a reasonable price.


Seatpost clamp arrow and too wide saddle rails

Thank you. I actually just screwed the clamps in and it seems to work pretty well.
None of them (top and bottom seemed to fit.


How do I use retro drop down handlebars with no hoods?

You have the option of purchasing a product such as this:

These are secured to your drop bar where your brake hoods would normally reside. They provide a hand position on the ramp of the bar without having to use drop bar brake levers. They also can install directly over your tape (but it will eventually ruin the tape, so ideally you'd install them and re-tape everything.) While it would be the cheapest and easiest option, it doesn't address the issue of your hands being away from your brake levers (which is a very important feature when riding in traffic!)

The existing brake levers are Tektro RL720s. They're known as "interrupter" levers because they are generally installed in tandem with drop bar brake levers and they interrupt the housing, creating two sets of brake levers at two different hand positions. You could purchase any aero levers and install them on the bar along with the 720s (they need to be aero levers where the housing runs under the handlebar tape). This would require some housing and new brake cables, but it would solve both the hand position and brake access issues you've posed for ~$40.


Replacing the front derailleur: unlink the chain?

If your chain has a powerlink, you can disconnect it pretty easily. Otherwise, it is pretty straightforward to open up the cage and slip the chain out. It shouldn't damage it (as front derailleurs are pretty simple mechanisms).


Knee feeling after long ride with road bike

If you ride further or faster than you're used to, then some weariness in the legs is normal and should pass within a couple of days. I rode my biggest ride to date a couple of weeks ago and when I got home I nearly lost my balance walking around the house as my legs were a bit weaker than I expected. With a couple of days rest they were back to normal, however.

Besides rest, what can help your recovery is static stretching (not bouncing or bobbing). Here are some suggestions for knee stretches.

As others have suggested, a higher cadence (therefore a lower gear) may help, even if you can't measure it precisely. I have a knee injury from running, so I change down a gear the moment it gets uncomfortable.

For bike fit, trial and error can work well, here's a link to some simple bike-fit tips which may help you move in the right direction.

All that said, if discomfort becomes pain you should obviously stop doing what hurts and get advice from a physio, ideally one with cycling expertise.


Old Kalkoff cross bike, worth restoring or not?

That isn't a cross bike. First, make sure the bike fits you. If it doesn't, its not really worth restoring (give it to someone who could use it). It looks to be spec'd with relatively cheap stuff, so I wouldn't sink a lot of money into it.

The first thing to check is if the frame has any major cracks or damage. If that is in good condition, check the headset to make sure its working smoothly, that the fork is functional (it probably doesn't work well, but if it bottoms out automatically its relatively useless), the pedals turn smoothly, tires hold air, wheels are true, brakes work (probably will need new pads), shifters work, chain is OK, derailleur not bent. A lot of this will likely require elbow grease and real grease/oil rather than new parts.

If the fork is in bad shape, you can likely pick up a rigid fork for not much money, but you need some tools to install it which probably means a trip to the bike shop or local co-op. If you take it to a bike shop and ask the guy to give it a safety check, he should be able to quickly determine what needs to be replaced for a few bucks. As for aesthetics, well, not much you can do there.

In all likelihood though, all you're going to need to do is oil the chain, adjust the brakes , adjust the derailleurs, throw on some new brake pads, adjust the cables (some may be broken and need replacement), pump up the tires, adjust the seat and handle bars and you're going to be riding off.


What is this fender part called and where do I get one?

You could try finding the fender online, and then see what parts come with it.


Mysterious case: chain falling off large chainring, how to fix?

Yeah. A modern double chainring is ramped and pinned, in order to be more easily shifted from one ring to the next. Simply put, the chainring "wants" to pass off the chain to the next cog. Without a derailleur to keep it in place, the lateral pull of the chain shifting across the rear, combined with some road jostling, can make the chain fall off the front.

A couple solutions:

install a singlespeed chainring without ramps or pins, with "straight" teeth.
use an outer chainring guard and inner "dog tooth" chain keeper
combine the two (which is the best solution).

The free and easy way to keep it on while looking at other solutions is to reinstall the front derailler and adjust the limit screws so it keeps the chain in place.

This is a pretty common concern with cyclocross. Racers often use a single-chainring setup for the sake of reliability, and either or a dual chainguard or chainguard-and-chain watcher setup for just such reasons (also because they keep picking the bike up and putting it down whilst running and jumping over stuff), so you get stuff like this: http://www.bikeman.com/CC-SRAMS300CX.html.


It it impolite to "informally" join or draft a group of cyclists?

It can be considered "impolite" by roadies, but not because of the bike you were riding or the fact you didn't take a pull (although I am sure some will argue for this).  The main reason random drop-in riders are generally frowned upon are because of:

the dangers associated with unpredictability of a new rider
lack of insurance coverage

Potential Unpredictability

New riders can behave unpredictable especially in a pace line.  In the same way, groups can  behave differently than you might expect even if you are an experienced road rider.  Jumping into a group without knowing what they are doing can lead to unanticipated behaviours which may or may not result in a crash.

From the groups perspective, they don't know if you are a stable rider or if you will try to ride too close and clip a tire.  They don't know if you will block one of them when they try to rotate their positions.  You are a complete unknown who has just shown up.  Most people are suspicious of unknown factors.

Likely they have also spent a lot of time training.  Maybe they are racers.  Maybe they are getting ready for a charity ride.  It doesn't really matter.  The last thing they want is to get taken out by someone looking for a quick draft or thrill.

Anecdotal Experience - Collision

I was starting to get ready for for cyclo-cross a few years back in August and part of my route was on the road with a transition to some local trails.  On the transition from road to dirt I usually hopped off the road to the shoulder, scrubbed about 10 km/hr in order to make a sharp turn on to the trails.

On the road I was in my drops plugging away on an interval when unbeknownst to me someone on a road bike had snuck up behind and was drafting me (my road section began at the bottom of a hill so I suspect this played a big role with suddenly picking up a rider). I was pushing hard on the flat so I suspect he was drafting tightly. When I sat up, to get ready to transition onto the shoulder, he collided into by back wheel.  I hadn't hit the brakes yet, but he must have been drafting me tight enough that simply letting off the throttle was enough to cause a collision.

Luckily we were both ok. I was livid that he was drafting me without notice and bent my wheel.  He was livid that I didn't continue my pull to where he figured I should finish (at the very end of the road).

This belies the danger of an uninvited riders. NO COMMUNICATION had occurred between either of us as a result there was an unanticipated maneuver which lead to an accident.  NO COMMUNICATION while riding in close proximity is dangerous.

Insurance

For a number of years I was on the board of directors and/or running a large cycling club in western Canada.  Insurance, believe it or not, is an important consideration for a club.  We can't hold training rides or other official club events without it.  One of the Caveats is that everyone on the ride must be properly insured. For a new rider this can mean signing a one-time insurance form.  For other riders it can mean belonging to either our club or another club and being a member of the local cycling licensing organization.  If an incident happens and someone is injured (I have attended many  ambulance visits over the years from group ride mishaps) and it is caused by a rider that showed up uninvited this could void the insurance coverage.  We would have to prove that you were not invited, and that we didn't mess up our insurance forms with respect to your unofficial attendance.  If people are recovering from injuries the last thing we all want is to deal with lawyers and a court-of-law.

We are not deliberately unfriendly

All the above reasons may seem very unfriendly, this is not the intended effect, it is just the consequence of the world we live in.  If you are interested in attending a club ride, contact one of your local clubs (a quick internet search away).  You will likely find that:

Most clubs will have a relaxed "C" group where you will be taught
the ropes.
They will be able to go over group etiquette and how the group works. For example:

where we double up pace line;
where we single up pace line;
average speed;
how the group should operate around traffic signage;
how to point out obstacles and road hazards to drafting riders; and
riding route

Most will not care what bike that you ride.
And finally, they can ensure you have filled out the proper insurance forms.


As @Carel mentioned, try using rubbing alcohol to clean the discs. It's often called Isopropyl Alcohol or isopropanol.

You may have inadvertently contaminated your pads which often means replacements. Did you use any sprays which may have blown on to the disc? Frame protector and water displacers like gt-85 or wd-40 will play havoc with your braking power.

I suggest taking the pads out and keying the surface with some emery paper. It'll take a little while to re-bed them in but it might bring them back to life.

If a contaminant has soaked in to the pad too deeply though you'll need to swap them out.

You may also want to take the opportunity to re-centre the calliper whilst you're tinkering.


It's not good but it's a fairly common problem and there's nothing you can really do about it short of replacement. Shimano doesn't sell replacement caliper internal parts or rebuild kits.

Oil there is capable of getting worked on to the pads or rotor, possibly causing sudden loss of braking power.

Pistons getting extended too far is something that should only happen by accident when the wheel is out. If it leaked some oil then and only then, that's not something to be alarmed about. Likewise, if it only leaks immediately following a bleed, or it had some leakage there when new but not again, that's annoying and not something it "should" do, but probably (and only probably) not an indication of bigger or imminent problems.

If it does it all the time in normal use, I'd recommend replacement.


Shimano GRX groupset with mechanical brakes for CX/Gravel

The 2019 European Champion thinks Ultegra is quite fine for off-road https://www.cxmagazine.com/bike-profile-yara-kastelijn-stevens-super-prestige-cyclocross even for the 2019/2020 season. And yes, she is using 1x, although with hydraulic brakes and Di2 (electronic shifting). Many professionals are using Dura-Ace with 1x.

There is a difference in the brake lever (perhaps only the Di2 lever, see the comments) in the GRX shifters to allow more efficient braking from the hoods, but it is not considered essential yet. Many people do without. All other top non-GRX shifters should be pretty similar as the Ultegra.

I do not know if the the unconnected left shifter would feel weird, as Michael suggests, but GRX would be the same. You have the option to connect the GRX shifter to your dropper post. But if you don't have one...

As for the Apex, the front part of the groupset is independent, so you can have it and as long as you are only using it for braking the only wierd thing that remains is having two shifters with a different shape o one bike. It might feel or look strange. If you change everything to SRAM, you would have to be switching shifting between bikes, but many people manage with that.


Just a 10mm allen wrench was needed.  Looking at the head for the bolt, it looks special, but its not, so I was deceived.  Probably not a traditional bolt head, as the axle must fit through it.


Is cycling on this 35mph road too dangerous?

As an experienced cyclist who has been all over the country and even done hundreds of miles on interstates, after finding that location on Google Maps, and checking  how you might conceivably get there, there is absolutely no way in hell I would ever be caught dead there on a bicycle.
How you answer this question is not by taking one isolated photo out of context, but by looking at the totality of how you would get into and out of the location on your bicycle. By doing this, we can quickly see that it would be unwise to use this road, and a serviceable (and far safer) bike path alternative exists.
There are two ways to get there: The first is to exit H-1; your picture was taken where that off-ramp merges with Nimitz Hwy. I won't discuss this further as it would be illegal to cycle there anyway.
The second is to enter Nimitz Hwy from Kamehameha Hwy at Middle St here:

That means you would have to ride in one of the two left lanes, likely in the middle of heavy traffic, from at least there until you merge with H-1 later on up the ramp:

You would be cycling in the lane where this picture was taken, and would then have to cross those two lanes to the right which are full of cars coming off H-1. This is extremely unsafe unless there is virtually no traffic. I might do it at four in the morning. I would not go anywhere near it in normal waking hours.
Fortunately you don't have to. Just to the right is a bike path which runs parallel to this bit of Nimitz Hwy, ending at Peltier Ave. The sidewalk on the right turns into the bike path just after Middle St:

Instead of trying to play Frogger with high speed vehicles up above, I'd use this bike path.
Given that it's pretty much impossible to get to the point in your picture safely, I've omitted the analysis of how to get out safely.


how to remove through axle on raleigh 2.0?

It seems that you have through axles front and rear, most likely 15mm (the Raleigh site is unclear).

The sequence for installing the wheels is shown on this Fox front fork page:

If you're screwing the QR lever around the axle you're almost certainly unscrewing something you shouldn't. Try closing the lever to the locked position, screwing it tighter, then when you meet resistance open it, screw another half turn, then close it. You should find it takes a little pressure to close, but still locks the wheel in place.

The animation and detailed instructions on the Fox site might help.