For pure road-riding: Neoprene covers over normal road-shoes are the best as long as you don't have to put a foot down too often. The cleats are prone to clogging in snowy conditions. But then you wouldn't certainly get on a bike. On the other hand, ankle hugging covers keep the rain running down the legs into the shoe, which could happen with insulated boots.

For cross-country riding or commuting: Specific insulated and waterproof (membrane-type) shoes with profiled soles for MTB-cleats and MTB-pedals are a very reliable solution. MTB-cleats and pedals by design cope better with adverse conditions like mud and snow. And the shoes are more wear resistant than covers if you need to walk longer distances and there is less trouble to put them on and take them off.


Before you take any more forceful measures, it may be a good idea to think a little about chemistry:

'Rust' is typically the name put on any type of corrosion, but technically & specifically, it is the corrosion of iron (or steel) to form iron-oxides.
Although your bicycle is most definitely steel, your seatpost is not -- it's aluminum-alloy, which does not 'rust', but definitely corrodes (creating aluminum oxide).
WD-40 is a penetrating oil which is designed to, amongst other things, break up iron-oxides. However, it is pretty much useless against aluminum-oxides, especially when they have already corroded & bonded.
Ammonia, however, is spectacularly good at eliminating aluminum-oxides.

Therefore, if WD-40 isn't doing the trick, get some ammonia, apply it in a similar fashion, and let it sit. It may just be all you need!


If I currently have 700x23/25C tires on my bike, will 700x35C winter tires fit?

35c might be a bit too wide for your rims, maybe 32c would be a better choice. They may fit your wheels just fine, but they may or may not rub on the chain stays, seat stays or the brake caliper.

35c tires are not only wider, but also have a larger outside diameter than than their smaller counterparts.

If you have enough clearance on your frame & calipers, you should still consider how big of a change in size you want to try.

Consult the chart below to help determine if they will fit.

From Tire Sizing Systems

  Width Considerations

  Although you can use practically any tire/rim combination that shares
  the same bead seat diameter, it is unwise to use widely disparate
  sizes.

  If you use a very narrow tire on a wide rim, you risk pinch flats and
  rim damage from road hazards.

  If you use a very wide tire on a narrow rim, you risk sidewall or rim
  failure. This combination causes very sloppy handling at low speeds.
  Unfortunately, current mountain-bike fashion pushes the edge of this.
  In the interest of weight saving, most current mountain bikes have
  excessively narrow rims. Such narrow rims work very poorly with wide
  tires, unless the tires are overinflated...but that defeats the
  purpose of wide tires, and puts undue stress on the rim sidewalls.

  Georg Boeger has kindly provided a chart showing recommended width
  combinations:

  Which tire fits safely on which rim?

   Note: This chart may err a bit
  on the side of caution. Many cyclists exceed the recommended widths
  with no problem


Simple idea - turn the wheel over in the truing stand.   The low side of the rim should move to the other side.

If the Right-hand side is still low after flipping, your gauge is out and needs calibrating.


Purpose of 'bore' on spoke nipples - why are spoke nipples not threaded through their entire length?

Adding threads to any sort of bolt under tension doesn't actually make it much stronger, beyond the first ≈5 threads. Adding more basically just adds dead mass; either way the whole thing will generally fail somewhere close to the first thread. So, filling the bore with threads wouldn't have any benefit. What it would do however is move the expected point of failure out of the relative safety of the unthreaded bore, which particularly protects the spoke from being bent at that point, which would further diminish its strength. The bore makes it so that if there's some bending, it will be on the unthreaded part of the spoke, which is stronger to begin with, so not as worrisome.


Mountain bikes are fine for road commuting too.  The advantages are fatter tires which make the bike more stable and the upright riding posture, which many find to be more comfortable compared to road bikes.  This disadvantage is mountain bikes aren't as efficient.  You'll need to expend more energy to get to the destination compared to a road bike, due to wind resistance (from the upright riding posture) and tire friction (from the wider tires).  You may get there on a slightly slower ride too, so it will take a tad longer.  Still, I think a mountain bike is a good choice based on what you say.

What I'd look for is a good quality aluminum (or cro-moly steel if they still make them) fully rigid frame, and , most important, Shimano's economy components all around.  Skip everything that is unnecessary, like disc brakes, hydraulic brakes, 10 and 11 speed cassettes, etc.  Stay with traditional cantilever or V-brakes (really just another type of cantilever).  The more basic, the better.  You could easily get by with 10 total speeds, in a 2 x 5 configuration, though I doubt you'll find that available, but the few speeds, the more robust the drivetrain will be.  For the frame, the more standard, the better.  Avoid unusual drop out dimensions, etc.   And, most important of all,  the more the component set is one that sells in large volumes, the better.  It will be much easier to obtain parts in the future.

After that the most important thing to look for is fit.  Take a test ride on at least 3 or four bikes of various sizes before deciding.  If you think you might want to use the bike for actual mountain biking -- like riding on steep dirt trails -- error on the "too small" side rather than the "too big".  Otherwise, just choose the size that seems to fit best from the test rides.


Would silica gel inside my bike frame be effective in preventing corrosion?

No, it wouldn't work as long as the frame is not hermetically sealed to keep water from entering (I don't know why manufacturers don't do that).

The silica gel can only absorb a tiny quantity of water, a drop or so per packet, then it becomes ineffective. It is only effective to absorb water vapor.

You can bake it in the oven to regenerate it.
If you want to play with it, there is a version with a water-sensitive dye (blue -> pink, now illegal because of cobalt content) and orange to a bit less orange. If left open, it will change color quickly.


Would you ride with this tire with cuts in the sidewall?

I would not ride that tyre.  Pretty sure I can see tube in the second photo, and that's asking for a sudden blowout.

You might choose to put a boot/patch on the inside of the tyre, and use this as an indoor trainer tyre only.   Might be okay on rollers, would make a great front-wheel tyre for a direct-drive trainer (ie, the wheel that doesn't turn at all.)

I certainly would not ride on the road with that ever.

It is dead, buy a new tyre.


With most older quill stems, there must be a minimum of one inch of the stem (above the binder wedge) inside the frame for safety.

Most stems have marks on them similar to seat posts, yes. The longer the quill, the more of the stem needs to be in the frame. I suggest 25% of the length as a minimum.

The scratch marks on the stem in the photo you linked show about where that one should be inserted as a minimum.

Yes, you can loosen the bolt and slide the stem farther up, to raise it, with this style stem. How much you can raise it varies by model and your frame.


Save your money and get a used bike instead (look for bike shops in your area that sell used bikes, or craigslist or something). 230 dollars should net you something decent from the 80s or 90s, along with some accessories (helmet, locks, lights, etc.). It'll be much higher quality than what you're looking at (the bike you've linked is bso-ish), and older road bikes have much larger tire clearance normally than newer bikes.

One of the big problems with buying your first bike online is sizing -- not everyone fits the sizing charts bike manufacturers may publish. And you don't get a test ride online to know if it will fit you well.

The C&O canal towpath just has a bit of gravel on it, not much terrain toughness. I'd not worry about knobs, just 28c+ tires. As for sizing, you have to try the tires with the particular bike, especially with a road bike. Normally with modern road bikes, you can maybe go 1 tire size up with a smooth tire compared to whats originally spec'd. You've gotta check the tire clearance to see if the tire will fit (also note that two new tires will run 40+ dollars on the low end). So, I'd conjecture that the 28c tire won't fit.


Uneven friction in front hub after rebuild

Disassemble the hub, clean away the grease, and carefully inspect the surfaces of the cups and cones.  If you see irregularities then that's probably "spalling" and it means that the part must be replaced.


Clipless pedals, saddle height and proper starting (and stopping)

The rule of thumb of "the highest possible without wobbling the hips down to reach for pedals" seems like a better rule than "having the barefoot heel just touch the pedal with the leg completely straight when the pedal is completely down".

If your saddle is at the right height, it should be difficult to place a foot on the ground while seated. Now that your saddle is at what seems to be a more appropriate height, you may have to change any habits that developed during the time that you had a lower saddle.

Remaining seated on the saddle at a stop is uncomfortable on a well fitted bike. You should find stops much more comfortable if you stand over your top tube with one foot flat on the ground. With a bit of practice, you should be able to use a single push with your foot to simultaneously begin to pedal forward while lifting yourself onto the saddle. Clipless pedals make this easier because you can easily position the crank by "pedaling backwards" to the desired position. With a little bit of practice, this will become perfectly natural.


Trying to tighten a saddle clamp but nothing seems to give

It may be a silly question from my side: Did you loosen the bolt on the seatpost clamp (the one above the blue tape)?
The saddle clamp isn't screwed in but either shrunk-fit or glued in place. So your seatpost is toast. Removing a stuck post is a classic problem. It can be very hard, if the post hasn't been taken out for a long time and put back with a liberal coat of grease, anti-seize paste or carbon compound if either post or tube, or both are made of carbon.
To remove the post, try first with penetrating oil and letting it soak for plenty of time. If you can rely on a mate to hold the frame grip the post with a water pump wrench. Be careful though not to damage your frame.
On YouTube in bicycle dedicated channels you may find several more methods to proceed as it is quite a common problem.


Cassette jerks chain forward intermittently

Since the cassette is being driven by the wheel, the freehub mechanism is catching instead of releasing.

Confirm that by removing the rear wheel, remove the cassette, and spin the wheel/freehub off the bike (ie in your hands)

When powering it through the freehub the wheel should turn like normal, but as soon as the freehub is not driving the wheel, it should stop and will make a faint or loud clicking sound.    If you feel the freehub still being pushed around by the wheel, it needs work.

Fix0 - clean all the impacted dirt and oil, hair and grass out from behind the cassette and around the freehub.   Consider removing the dork-disk if its cracked or brittle or not sitting right.

Fix1 - blast the whole thing with cleaners, then let it dry, and lube it up again before use.

Fix2 - disassemble the freehub and attempt an interior service.

Fix3 - replace the freehub mechanism (last resort)


compatibility for a new cassette and chain

4600 is the previous Shimano Tiagra series (4700 is the current version).
As far as I’m aware all 10 speed cassettes have the same cog spacing, so you should  be able to use any 10 speed cassette and chain. More expensive cassettes are usually lighter and maybe stiffer which makes them shift ever so slightly better. They are a wear part, I wouldn’t spend too much money on them.
Note: The current Tiagra 4700 groupset has different pull ratios for the derailleur and shifter, but that doesn’t affect the cassette spacing.


What kind of gear shifter is this? Single lever

I'd call it a thumb shiifter.   Guess its for the front derailleur, and on a bike that old its probably not indexed, which makes this easier.

Firstly is the gear wire loose?  Check them down on the frame and see if they're slack.  If so, the wire has snapped or the end has come off inside the shifter.

If you can't physically move the shifter then it could be jammed with wire or the "barrel", or just plain rusted.

That plastic bit on top is a handle- its the top of the tension screw.  If you undo it completely you'll be able to see into the mechanism for rust.  This is also how you'd get access to the cable to replace it.  Note your other-hand shifter is more likely to be indexed (ie click-stops at every gear position) so not directly comparable.

If the problem is rust, tell your friend to stop storing the bike outside.
If its a broken cable, that's a fairly straightforward fix, albeit dirty.


Which type of bike is the right for these conditions?

It sounds like what you want is a gravel or adventure bike.

There is not a distinct category, and different manufacturers use different names, but the basic attributes you are looking for are:

Road bike style frame, ISO 622 rims, drop bars
Clearance for up to about 40mm tires
Disc, linear pull (V) or cantilever brakes
Slacker steering geometry
More relaxed body position

There is a blurry line between this type of bike and a cyclocross bike. True cyclocross bikes have recently moved to 1x11 drivetrains. Unless you live in a very flat area you should opt for a bike with a double front chainring.

There are offerings from many manufacturers with aluminum and carbon fiber frames (and some steel) at a variety of prices. You can also look for a used bike.


Do they still make rear shocks with remote flow control valves?

The shock you are referring to was marketed as a 'brain' shock I think. The worked by varying the damping based on detected rear wheel movement. As far as I remember only specialized sold them, first produced for them by Fox and then an in house model. They typically appeared on more XC orientated designs and I've never seen one available as a separate retail product.

Fox have been working on a very similar concept using electronics instead of a remote 'brain' to vary the damping. See http://www.pinkbike.com/news/exclusive-ride-report-fox-live-valve-active-suspension-system.html for more info.


B-tension issues rarely pop up spontaneously. Once it's set, you usually don't have to ever touch it unless you change to a much larger or smaller cassette. Unless you messed with it already...

I see the scrapes on the derailler and think your DR hanger is probably bent. This can cause irregular shifting issues like you mentioned-- good in the lows but bad in the highs, or vice versa.

Or, your cassette/ chain might be worn out. Do you usually ride in the big cogs? If so, those will be the first to wear out and they might not shift right, while the unworn smaller cogs still have the sharp ramps to shift well.


How do I make sense of Bontrager Tire Models?

They are indicators of what product line Trek is placing each tire in. For example, R=road, AW=all weather, t=Touring, XR=cross road (or something like that, indicating smaller tread that is not too big for mixed road riding) G=gravel and so on. I would say that these prefixes don't really mean much, just choose a tire that is appropriate for the type of riding you will be doing.


Some rims have a small-diameter drilling for presta valves, so a schraeder (car-type) valve won't fit.

If your rim is drilled for schraeder valves, you can use presta valves, but you should use a plastic adapter sleeve to hold the valve in position and avoid wear to the valve stem or the edge of the drilling.


Helmets are like hats and shoes — everyone has a different shape head or foot and so the standard sizes really don’t apply. Some heads are pointy, some are flat. Different helmet companies use different head forms — and some even use different shapes between their different helmet line. So a ‘L’ for one helmet might not be the same as an ‘L’ in another.

So I’d recommend going to your local bike shop and get a properly fitting helmet. You’ll be surprised just how much better it fits on your head and how much more secure it is.


It's a wrench that will work on a range of different size nuts and bolts. Each step on the top ramp will grab a different size. A further advantage is that it will work equally well (or badly) on four sided nuts, and on five and seven sided "security" bolts that a conventional adjustable wrench with parallel jaws will not work on.

It will not work especially well, but it's a one-piece equivalent to a proper adjustable wrench, which in turn will not work as well as a proper set of spanners. They're made because they're cheap, light, and easy to manufacture.

Edit: found the ad on ebay and it has another image:

Since it's only about 10cm long, it seems to be about 2mm thick based on the image above. So Daniel might be right, it would work for holding cones and locknuts in place. Wandering the internet I haven't been able to find anything similar, unfortunately, but I recall seeing them in some collections of very old tools.


Machining a 9000 series inner chainring to fit on a 9100 series crankset

Here's the difference in the chainrings.

Shimano might have modified one attachment point to ensure that the ring is oriented correctly. There does not seem to be any differences in the teeth though.

As Shimano removed some material, it's obvious that you can. It would be possible to simply mark out the profile of the modified arm, hand file away the extra material and test fit as you get close to the line. Filing with reasonable precision is not as easy as it looks but there are many videos online that show you how it's done.

If you need to get someone to do it for you, look up local machining shops.


Hitting bumps on a locked out suspension fork

I have read about damaged lockout systems from big hits while locked, so my advise is treat a locked fork as a fragile fork unless you want an expensive repair bill. Probably the key point is what is "a hard hit" and "high load"  for a fork? That said, I have taken a couple of what I would call big hits with my fork locked with no damage, but I weigh under 70kg and what I call big is probably nothing to some people.

The manual for the Suntour forks is somewhat contradictory. In one line it says "...This system protects you when riding in demanding terrain in case you forgot to unlock the fork."

Then immediately it states
"...The fork may become damaged when it is compressed under a high load...."

The take away I get is it protects you but will possibly be damaged. In your case, I would suggest cranking up the pre-load when on the road, and only using the lockout when you know there are no potholes around.


Combining Shimano RS500 crankset with Stages Shimano 105 5800

Many individuals are running non matching hollowtech II stages crank arms with no ill effects.

Stages themselves cites this as OK.

Note the Dura-Ace crank below.

Crank Compatibility: All Shimano Hollowtech II road cranks

Go ahead and purchase with confidence and enjoy cycling with power.

I run an Ultegra 6800 Stages on a 6700 Crankset personally.


Chain slips off biggest cog under torque

Your first image suggests the chain is not meshing properly with the chain ring.  After 8000 km you should be either just finished your fourth chain, or about halfway through the second (depending on if your manufacture says 2000 or 5000 km per chain.)   How long since the chain was changed?

Do a chain length check too - 24 half-links (12 pairs of inside and outside) should be 12 inches long.  Any more than 12 1/8th inches is too stretched.   Running a worn chain normally wears out the rear cassette, whereas the front ones tend to survive because of the greater number of teeth.

Finally - use a straight-edge and confirm the front chainring is not bent.  This can be seen by eye if you turn the pedals while looking down from above.  A deflection could cause a bad meshing.

Over-lubing itself is not as issue.  However it attracts dust dirt and sand, which can do mischief on the chain, accelerating wear.  Best practice is to clean the chain, dry the chain, and then oil the chain.


What bolt size are Shimano brake caliper bolts?

On the approximately 5 different models of Shimano disc brakes I've dealt with over the years, the caliper fixing bolts are M6 x 18.7mm, and they are socket head cap screws in non- bicycle parlance. This length of fixing bolt would be if you were using 160mm rotors in a post mount set-up.  For systems using 180 or 203mm rotors, you'll need about 40mm of length on your caliper fixing bolts to get thru the caliper and the associated adapter.
At farm, home, or hardware stores in their bolt bins you will find in their metric section, "socket head cap" screws (they will have the blunt end like a bolt, but they are screws because they are used by screwing them into existing threads, not with an associated nut.  That's then a bolt.) The closest length you'll get is 20mm, though some places may have 18mm M6 socket heads in stock. They'll also have 30 and 40mm lengths typically.
While you're there, purchase some blue Loctite 242 (aka, threadlocker blue) and follow the instructions for that using it on the caliper fixing bolts (well, they're screws, but Shimano calls em bolts) when you go to mount your caliper.  And tighten to the recommended torque value range of 6-8 Newton-meters (50-73 inch-pounds).
Properly torqued fasteners with threadlocker will not "come loose" without mechanically assisted human effort.  It's still a good idea to check the fastness of your calipers before every ride and recheck with a torque wrench every so often, especially after the first ride or two after install.


How to avoid riding on a gravel on the road sides? + Riding through traffic lights

Depending on your local regulations, claiming the lane might be illegal (it is here where I live, for example). So, my advice would it be to ride on the right side of the road (assuming that right is the driving side), but not getting too close to the curb because of the debris, gravel, car doors etc. When you see (and hear) someone behind you wanting to overtake you, just move some to the right (and optionally give him a sign with your hand).

However, don't go to the right if you see that they can't overtake you safely, i.e. if the road is too narrow there, or if you see a car coming from the other direction.

On the traffic light, claim the lane! That will prevent drivers cutting you from behind, while it doesn't bother no one (you occupy less space than a car, and they are not waiting for you, but for the light anyways). When the light opens, and you pass the intersection, return to the right part of the lane.


How much axle space for the cap nuts and chain tugs?

I would first try a standard nut on the axle because often the cap nuts have a nice rounded entry to the threaded area which means the trhead doesn't start for a millimetre or so. From the photo it looks as though you should have enough axle for a standard nut to work.

The next step is to grind off some of the antirotation washer so your nut gets more space. Those washers are made of a nice hard steel so they're hard to file. Much better to use a power tool if you can. If not, get the finest, sharpest file you can. And try very hard to keep the surfaces of the washer parallel - if they're not you are much more likely to strip the nut.

And Neil Finn, the cable attachment shown above is the less problematic of the Shimano 8 speed ones that I've seen, but it's still prone to sticking bits of broken gear cable into your fingertips. Note that hhh has a broken strand and there's no end cap on that cable. Unless it's soldered it will eventually fray and then grabbing hold of it to fit it back into the hub gets ugly.


Rear hub-adjuster thing - What does it do?

The dangly adjuster thing is most likely the toggle chain for an internally geared hub!

The tension on that chain shifts the hub internally (rather than through a derailleur and cogset). Bike hacks with three-speed hubs are quite common, but get very complicated. Here is some information on Sturmey Archer hubs courtesy of Sheldon Brown.

Below is a picture of the toggle chain and rod which is attached to the inside of the hub. Good luck!


Tips for dexterously handling bike lights with winter gloves

For similar fine tasks, silk inner gloves are ideal. They are very thin but add a noticeable amount of warmth. Their real benefit comes when you remove the outer gloves and have essentially bare hand dexterity with some insulation. Then you just have to get your timing right to minimise the amount of time your outer gloves are off.

Some people use latex or nitrile gloves in a similar way but I find them too sweaty.


I got a Topeak Pocket Rocket a few years back at the LBS spring sale for ~$25. Works great. I made $10 the first time I used it because I didn't have to pay a $35 cab fare to get back home after a flat on a country road.

Fits in my pocket, the nozzle has a snap-on cover, works with Presta/Schrader, it's made of aluminum, feels solid and most importantly gets my tires to an adequate pressure.

For floor pumps, you can check out this thread: What is the best floor pump?


Can a 7 speed torpedo cable index a modern day 7 speed freewheel?

You've answered your own question.  It all comes down to cable pull, so use an accurate measuring tool like a vernier caliper, and see exactly how much cable is pulled per click.  Use a dot of white-out ("twink") to help measure accurately.

The cable itself is quite irrelevant, its the shifter on the handlebar that does the stepping, and the deraileur has a multiplier ratio.

There's a great table at http://blog.artscyclery.com/science-behind-the-magic/science-behind-the-magic-drivetrain-compatibility/  but it doesn't list IGHs.

Shifter cable pull (mm) * Derailleur shift ratio  =  Cog pitch(mm)

So if your cable pull was 2.9mm per click, and the 7 speed RD mech had a 1.7:1 ratio then it should fit a 7 speed cassette/freewheel with the standard pitch of 5.0 mm


Replace vintage barrel nipple Shimano shifter cable

It's a Shimano Positron shift cable.
The outer housing is also special.

Picture from WorthPoint.com
I found a few for sale on ebay - not an endorsement.
There were two Positron systems. The first one was very complicated. The since there was no return spring the rear derailleur had two cables to pull back and forth. The later version had one solid wire cable that could both push and pull. That's why the cable end is so strange. The posted question refers to the second version of Positron.
There were many bikes sold with Positron shifting. For example, there was a version of the Schwinn Suburban in the late 70s that had Positron shifting with the FFS or Front Freewheel System.
Page 15 of the 1978 Shimano catalog has pictures and information.


Hayes Sole Disk Brake sudden loss of pressure.

Sounds like a major fluid loss, somewhere. Check around the hose joints, and the brake levers and calipers for fluid leakage. If not, it's probably a blown piston seal, which in rare cases can leak, but reseal under low fluid pressure.


Which master links for 1/8 inch aka BMX chains?

I suggest asking your local bike shop (LBS) because I've never seen a bike shop that doesn't have them, and they're only a couple of bucks. I found the three piece master links easily enough (on eBay and Amazon). You might prefer the two piece style in silver (Amazon)

I searched for "bicycle master link" rather than BMX to get those results.

For single speed chain I'd always use a master link, but with the narrower chains I often don't bother. But I rarely take the chain off the bike, preferring to run it through the chain cleaner on the bike (but I don't get my chains very dirty). For a single-speed it's possible that a really dirty chain would be easier to clean off the bike, but I still try on the bike first because itś so much easier.


This part is generally called a "brake pad retaining bolt" or often only "retaining bolt". They differ between brake brands and sometimes models, but a quick search for your brake model and "retaining bolt" usually turns up the right part.


MTB front suspension sounds like rusty trampoline

I think you answered the "cause" part of your question already - "long-term lack of maintenance".

Whether you want to attempt the rehabilitation yourself or not depends on your degree of comfort with that kind of thing. Here is a copy of the manual for the 2001 model (PDF file; make sure it actually matches what you have), which should help you get a sense of what's involved.

Just be glad they're not melted-down elastomer suspensions from the '90s like the last bike I inherited... yeeesh. :P


Are high racers safer due to enhanced visibility compared to low racers or classic recumbents?

In my experience, a higher bike will be seen easier and sooner than a lower bike.

I have had multiple riding events where I've been blocked or obscured by vehicles so another road user (driver) makes decisions based on what they know and what they can see.   If you've not been seen, you're not part of their decision.

Likewise, being lower provides a worse view, and therefore less information on the surroundings for the rider. I've had one night ride on my mid-height bent where it was also foggy, and could not see the road surface before it passed out of sight below my bottom bracket (front bracket?)  I ended up riding off the road into the gravel because the edge of the sealed road was not visible.

On the flip side, I have a strong but unsupported belief that once my recumbent has been seen, the observer is much more likely to notice me and change their actions if required.

The human brain has "layers" that roughly correlate to the embryo's stages of development.  For simplicity, the "reptilian" brain deals with autonomous stuff like balancing, walking, breathing, etc, while the "simian" brain is under willful control where you start thinking about breathing etc.

A road user while driving might observe a regular cyclist, and that information might never rise above the reptile level of brain.  The reaction is autonomous and doesn't bother the active thinking processes.

Observing a weird bike immediately kicks the thought up to management layers, where the simian brain has more of a reaction in the conscious space.

  tl;dr the lower the bike, the harder to see but once its been seen you're more likely to be considered by a driver.

I would not use a recumbent for primarily Central Business District (CBD, urban) riding.  My commute is basically 50% rural farmland, 30% residential, 10% park, and 5% dense city so I can ride 30+ minutes without stopping.   Recumbents like to just keep going, and a city environment doesn't encourage that at all with traffic controls and pedestrians.   Dooring near-misses tend to be more common when I'm on the recumbent too, but that may be observer bias (I ride the bent 95% of the time now.)


How do I know the model of my Shimano Torney SIS Index Rear Derailleur, I have a Vertical Henox T3 bike?

The first part to note is how the derailleur is bent. Is the frame aluminum or steel? If the former, is it just the hangar bent? (steel bikes typically don't have a derailleur hanger)

If the cage is just bent, you can take it to your LBS and they have a little tool to put in so they can easily unbend it (or you can do this with an adjustable wrench at your own risk, though i don't recommend it for people without experience).

If its just a hangar, you can spend the 5 dollars or whatever on a new hangar and be done wtih it.

If you do have to replace the derailleur, just get another shimano derailleur like a new tourney (these go for about 10 dollars) or acera unit - the rear derailleurs are pretty much all the same and the cheapest one will do in your case it seems (tourney again). Or check your LBS - they're likely to have a cheap one in their parts bin that fits. Then you can follow sheldon brown's advice to set the high/low limits and do adjustments.

Since the derailleur went into the spokes, I'd also get the wheel checked out.


How to choose the light bulbs for a given dynamo

Apparently the 1970s PX-60 (see the OP's comment  had a Soubitez bottle dynamo ("génératrice") on the rear wheel as sold. Similar looking vintage Soubitez dynamos come up on eBay, where sellers and photos both indicate that they're 6V 3W.

However dynamos labelled 16V 8W really did exist: They were made by Sankyo, and again appear on eBay.  They were apparently fitted to Raleighs and Schwinns in the 70s.  If that's really what the OP has, and the output is really that much higher rather than just being an optimistic rating, I could be tempted to try something like a 12V 5-6W incandescent bulb in the front, and 12V 1W at the back, if you can somehow make them fit.  These are cheap as they're used in cars, so getting a couple for testing would be reasonable, as would getting through them quicker than you'd really like.


How do you use a power meter to pace yourself during steep hill time trial events?

First thing to do would be to get some data about your max power outputs over different gradients & conditions.  So you'll want to know what you can sustain over a 10% 3 km climb, or a 10k climb at 5%.  You'll also need to know how this fits into different length rides - you'll be able to output a higher average over 15 km than you would over 30 km.

The relationship between power, gradient, cadence, gear and speed is complex.  Increasing power will cause your cadence to rise, thus speeding you up.  The steeper the gradient, the more resistance there will be, so it'll take more power to remain at a steady cadence (in the same gear).

Dividing your power by your weight will give you a watts/kg rating which is useful.

Once you know all this data, you'll be able to look at a hill and know that, all else being equal, you'll give your best performance if you maintain, say, 4 w/kg for the climb.  You can then use your powermeter output to adjust your effort accordingly.

Edit:
Mind you, if I understand the event description correctly, I suspect that over that sort of distance you are best off just pushing on the pedals as hard as you can.


Trying to find Derailleur hanger for a custom road frame

I think it might be Hanger #31 from Wheels Manufacturing:
http://wheelsmfg.com/derailleur-hangers/1-fastener-derailleur-hangers/derailleur-hanger-31.html
It's a little tough to see in your photo, but that's the closest I could find.


At what time of year can I buy a bicycle for the best price?

Probably not what you're looking for, but... if you live near a college campus and are willing to buy used, the end of May might be a good time to check Craigslist.


First: based on your measurements, your chain is not worn out. The park tool gauge measures a 8 1/2" links, or 4 inches of chain. It looks for wear between .5 and 1mm of "stretch" in the chain.

If you read the label on the tool, anything up to .5 is what a new chain wil read. A chain is not worn out until it hits 1mm of wear, which is when it usually will skip teeth on a new cassette or chain rings.

To protect you old chain rings and cassette, it is usually recommended that you change the chain at around .75mm of wear.

Second: Shimano's recommendation is that a new chain up to the .75mm mark is good for 880 miles on average. I assume that recommendation is conservative, because it often goes to double that in my environment, but speed of wear is based on maintenance and environmental factors like heavy wet weather, and can vary wildly.

I hope that is helpful.


Is it worth rebuilding a broken front wheel

You would need to cost it out, as it pretty much comes down to the dollars cents.

With a wheel at that price point its worth considering a rebuild, presuming you have a good wheel builder at your LBS. If you buy a new wheel, ensure the cost includes having the new wheel tuned up by the LBS. (If you not buying through a shop, add the cost having a shop tune it when it arrives).

Unless the hub has low miles, consider a full service with new bearings, or at least put the cost of this into the rebuild of the wheel.

In terms of if its worth it, you may decide reusing the hub rather than adding it to a landfill adds to the worth of a rebuild over a new wheel.


Replacing broken nexus 7 gear hub with second hand one

I took my bicycle to a local bicycle shop. They unfortunately told me that it should jump back to it's original position, and that opening the hub is the only way to find out what is wrong.

The good news is that all the nexus 7 gears can work with the same gear shifter. The nexus 7 SG7-R42 gear shifter is therefor compatible with the nexus SG7-R46.


If you're saying that, off the body, the sprockets move slightly relative to each other, that's not a problem.  The sprockets are only just "tacked" together so that they remain in the right order and orientation while off the body.  The body provides the strength to hold them.

If, on the other hand, you notice that the sprockets slide up and down the body after installation, or if they seem to wobble as they turn, that suggests that they were installed incorrectly relative to the notches or that a spacer is missing.


how to convert my 21 speed mountain bike into a road/cycling bike?

Start with your tyres. Go for slicks, the narrower the better. I used to run 1 1/4" tyres on my old mountain bike, at the time this was pretty much the lower limit on a 26" tyre. This will be by far the biggest bang for your buck.

It will probably also blow your $70 budget if you get good tyres. You may also need to invest in new tubes, depending on what you have currently. But it will make a big difference.

The other thing that springs to mind is to improve your position. Difficult to do this much given the geometry of the frame, although I have heard of people putting aero bars onto their MTBs. Should improve things but its more cost.

As for pedals - remember you'll need shoes as well - and these on their own will probably blow your budget. I'd stick with what you've got for now and think about upgrading as and when you have the cash.


Is there anything concerning about buying a half-price "test helmet" from my local bike shop?

A recent study investigated the impact performance of 675 used helmets (some as old as 26 years) without signs of damage.  (They collected 1500, and eliminated helmets with signs of damage). They all passed, except four. Three that failed were only made to meet the  old ANSI standard, and the only newer helmet to fail was a recalled model.

Because all of the helmets were used, some of the 675 would have been incurred some slight damage (e.g., being dropped, or bumped through regular usage) without showing direct signs of damage .  The fact only 4 failed, and those 4 had other issues, this suggests if you don't see visible signs of damage on a modern helmet, it is probably okay. In fact given the large sample size and consistent ability to pass the impact testing, I now have a lot more confidence in the quality of modern helmets than I did before.

For your helmet, makes sure to carefully inspect it.  If you don't see visible signs of damage you are probably fine,  assuming that the helmet was properly manufactured (i.e., NOT a grey market helmet), that it has passed all the modern certifications (i.e., check for the certification stickers), and that it was not a recalled model.


There is some variance in the manufacturers' claimed weight. Due to slight differences in the manufacturing process of the individual components, it is possible that the claimed weight was legitimate. If they weighed the smallest frame available and mated it to the lightest set of the specified wheels, the lightest saddle, etc, they could produce a bike that is lighter than anything that would come down the normal assembly line. Many brands specify that they don't list weights because of these variations. Some brands actually advertise the weight but don't specify the details such as frame size, was the frame painted, was bar tape installed etc.


Can a greasy chain cause the chain to come off the rings?

No.  A greasy chain won't cause the chain to pop off, and it would have to be exceptionally dirty for dirt to cause this.  (I've ridden many miles with greasy, dirty chains.)  Generally a chain comes off due to maladjustment or because of a worn component (usually a cog).

Poor technique can contribute to the problem, but the technique either needs to be pretty bad or there needs to be another contributing factor.


Rear Center Length
It’s the distance from the rear hub to the bottom bracket. More or less the chainstay length.
Unfortunately Reid Cycles doesn’t have a diagram of what and where exactly they are measuring. For example top tube length could be the actual tube length or a “virtual” top tube length (like in the diagram below) if the top tube were completely horizontal.


Why does my brake keep pinging out and almost killing me?

That looks like the quick release mechanism used when removing the tyre to open the caliper a little wider.

It looks broken? - it should be tucked under in line with the pull of the cable. Since it isn't the cable is actually pulling the release open as you brake.

You might be able to temporarily remedy it by leaving it in the open position and pulling the cable tighter. You would however lose the use of the quick release. Probably not a great idea to run it like this - since the cable will be pulling on the fixing nut at a strange angle.
Best replace with a new caliper.


There's a product called cat ears (reviewed here) that claim to reduce wind noise. They attach to your helmet straps and disrupt the flow of wind.

I've also found that headbands worn over the ears help a lot. Something like these are good. I even wear them in summer as they help stop sweat running into your eyes.


These bolts are usually 18-20mm long M6 bolts. The exact length isn’t important, but going shorter than 15 will likely mean insufficient thread engagement, while longer than 24 or so could potentially result in the bolt interfering with the rotor.
The plastic snap rings aren’t strictly necessary. They act as a second line of defense against the bolts inadvertently loosening. Shimano includes many of these secondary safety systems with their products (eg. safety clips on brake pad retaining bolts, threadlocker, fancy spring washers under rotor bolts, and these plastic things) which certainly will help, but the bike won’t explode if you don’t use them.


What should a big guy look for when buying a road bike?

Here's what I'd recommend

As others have suggested, you should avoid a stock bicycle. They're designed with the top of the bell curve in mind, and you're simply half-again as much man as the normal one. For more information on any of these topics, consult a bike shop!

Crankset: Since you asked specifically about them, I'll start here. The stiffest, strongest crank you can get is an a two-piece crank with an external bottom bracket. There are different types, made by different manufacturers, but they've been around long enough that they should all be durable (and as a bonus, better bearings!).
Sizing: The right size bicycle for you is determined by your leg length. A good shop should be able to measure you for the proper frame size. Along with stand over height, you should be measured for reach (which is a combination of your torso length and arm length), and handlebar width (measurement across shoulders, I believe).
Frame: Material doesn't particularly matter here. In the past, carbon has had durability issues, but that's largely been solved (so long as you select a quality manufacturer). However, with your budget in mind, steel or aluminum is a better choice.
Wheels: This is what you should be focusing a huge portion of your budget on. Quality, hand-spun, 3-cross wheels will last much, much longer than any pre-built wheelset.
Tires (tyres!): Be sure to select a wider tire than the old standby 700x23. I would even consider a 28, honestly. It's a small sacrifice in acceleration, but in terms of long-term comfort and cruising speed, a wider tire will be better.
Other components: What fits within the remainder of your budget. Road bike parts are super pricey, especially those fancy integrated shift/brake levers. Consider bar-end or even downtube shifters if you can handle it.


I think there's more wrong than you've spotted. Unless there's a chunk missing from the end of the axle or the dropout you shouldn't get any  movement under power or not. Bending a QR skewer is not easy to do, which suggests that there's a lot of force being applied, and it's obviously being applied where it shouldn't be.
Here's a picture of that model, and the rear dropouts don't look unusual at all IMO. I'm not a fan of the 5cm long unsupported rear extension, but it can be made to work (obviously enough):

I suggest looking for cracks in the frame, ideally by getting someone else who can sit on the bike and hold the brakes while pushing on the cranks. Wipe it clean, then get down and look for cracks opening up as they put pressure on the cranks and lean back and forth. The dropouts moving will definitely bend a QR skewer. And shortly dump you on the road, BTW, when the frame breaks. Look especially around both dropouts, but also the whole rear triangle. A seatstay breaking loose at the top could possibly cause this problem too (very unlikely but possible). The fix is, obviously, a new frame.
The other thing to look for is a chunk knocked off the front inside corner of the dropout. If the axle can grind into there under power that could also produce the problem you see. The half-arse "fix" for that is to move the axle right in the wheel so there's more poking out on that side. Which will work after a fashion for a while. The real solution is to replace the frame, and on a bike that old, that really means replacing the bike.

Edit: bringing discussion from comments up into the answer.
Matt says

the drive side dropout is definitely more chewed up (axle can move horizontally about 1mm) than the left side is which doesn't move at all. I checked to see if the frame was bent at all with the string method and it was exactly correct. Couldn't find any cracks either.
How insane would it be to have someone add some aluminum (fill in a little bit of the dropout) and then grind it back out to spec?

The issue is that the frame was heat treated after it was welded together. So when you weld it again you're changing both the alloy and the heat treatment. As a rule what you get is both softer in some places and more brittle in others (Murphy's Law says it will be soft where it's vulnerable to abrasion and brittle where it flexes). Even so, that is definitely worth trying when the alternative is throwing away the bike.
The worst failure mode is likely that dropout breaking off the frame, which will probably shove the wheel into the frame and you'll skid to a halt. So it's relatively survivable as such things go.

A buddy who I would trust on this said that JB Weld there is worth trying

Any kind of epoxy or filler is worth a try because it's cheap and reversible. But those fillers will be softer than even the original aluminium, so they will be ground away faster then ideal.
Another approach would be filing a little off the inside surface of the dropout to make space and gluing a steel plate in place, just because steel is harder than JBWeld. If you have access to basic metalworking tools and advice that's probably a better idea. Gluing steel to aluminium can be done, but use a specialist adhesive rather than generic "superglue".
I think your best bet is the aluminium welding solution. Remember that the seat stays are thin-wall hollow tubes and discourage the guy from welding to them, maybe focus just on bulking up the dropout. I'm not an aluminium-working guy, so I'm just suggesting that because I've seen some pretty ugly "add lots of metal" fixes that break because they're transferring stress to places that are not designed for it.


My AWC hub was incompatible with AW hubs.
I find re-spoking much easier than working inside 3-speed hubs.
I left those 3-speed bikes behind at a beach house, but based on memory:
- AWC internals are removed from the coaster brake side, while
- AW internals are removed from the sprocket side.

3-speed hubs that I disassembled seemed beyond repair,
but to help reach your own conclusions about relative difficulty,
this video seems representative:
 Clean/Lube Sturmey-Archer 3-Speed Hub - YouTube


Is it worth time to rebuild an old steel frame?

Buying parts alone is sadly a rather expensive way to get a bike and I doubt anyone would be able to tell you if it's worth it to you. That said, I'd be very tempted.

I like old bikes and it's better they get rebuilt and used than end up in landfill.

You should spec up the components you want/need and compare the price with a new one of similar quality and see which you prefer.


Older road freewheels vs new mountain bike freewheels?

I don't think old freewheels are "better" by default. While it's true that most of today's thread-on freewheels are junk, that doesn't promote the junk of yesteryear to "desirable" status. However, perhaps the median quality level was higher back in the day.

In the days before freehubs, freewheels, like most things, ranged from the downright awful to the excellent. Regina made brilliant freewheels, as did TDC and several others, but they command stupid prices on Ebay these days. And even if you can find a nice NOS example, it will probably need a rebuild to run optimally.

Obviously there was a much bigger market for freewheels 30 years ago, with a higher profit margin, so manufacturers could afford to construct them well. These days it's less economically viable even to invest in quality tooling, let alone top-notch materials. In addition, today's manufacturing trends have shifted further towards light weight, at the expense of durability. Our disposable culture doesn't consider this a great loss, I suppose.

Perhaps it's fair to say that the old freewheels were built to last, but the vast majority of them, even in great condition, would be considered "a bit rough" by today's standards, especially when compared to modern freehub technology. Sadly there aren't any really high-end freewheels on the market today for a fair comparison...

1970s Regina = Ferrari

1950s TDC = Jaguar

1950s Atom = Peugeot

2010s IRO = Peugeot

2010s noname = junker


There are an intersection of a number of reasons:

Public Perception - Carbon as that "wow" factor.  Colloquial it is associated with "space age"  technologies.  Therefore it must be better!  The truth is that the performance of carbon depends heavily on manufacturing techniques used (e.g., materials and layup).  See point 3 for an example.
Weight - Carbon has a high strength to weight ratio. Carbon forks really started to take a hold when steel was still a dominant frame material and during a period in the cycling industry when there was a serious obsession with weight savings. As such, carbon quickly became got the reputation of being material of choice for building light stiff components.  Compared to building forks from some other materials (e.g., an all steel fork) significant weight savings can be had. The weight difference to other materials such as aluminum however is not as significant, but once the public perception is set is hard to go against the grain..
Compliance - Because carbon has good fatigue resistance - it can be flexed nearly an infinite number of times without failure, if the force is less that the critical limit where structural failure occurs - this means it has the potential to be very compliant, if manufactured appropriately.  However it is expensive to customize carbon, because of all the molds required.  As such, many carbon components are intended for a wide use case (e.g., rider weight) and therefore are typically overbuilt for most people needs due to the failure mode of carbon being catastrophic.  As such, carbon forks (which are often lauded for compliance)  can also be harsh.  It really depends on how the part was manufactured and what your weight and use cases are.  Just buying a carbon fork does not guarantee a compliant ride.  For example, the most compliant fork I have ever ridden to date was a thin walled steel fork, it soaked up high frequency road vibrations like you wouldn't believe. My modern 2017 all carbon "endurance" bike with a "compliant" fork comes pretty close, but the difference is still noticeable (which I attribute to accommodating for disc brakes and thru-axle).
Ease of manufacturing - As others have pointed out in this thread, forks are separate components so it is easy to use another material here, especially if you can order forks at a good price. This makes it a relatively cheap upgrade on the production line especially considering point (1).
Economies of Scale - Because carbon forks have been popular for so long now, manufactures know how to produce them relatively cheaply now.  As such, this again makes it an easy upgrade (see previous point).
Quality cannot be visually determined - It is difficult (impossible really) to determine the manufacturing quality of a carbon fork by looking at it.  You need to scan or cut it apart.  This means that manufactures can opt for the cheapest fork possible but still maintain a look of high quality (assuming point 1).

From a functional/practical stand point I think there are many instances where carbon forks do not make sense (e.g., commuter bikes), but manufactures include them because of the public perception out there (which ironically manufacturers helped create). For most regular bikes, I think a steel fork is a more sensible choice: It typically offers a compliant ride and is more robust to physical damage than carbon; but many would view a steel fork as a step backwards simply because steel is colloquially viewed as an "old" material.

Don't get me wrong, I think you can build a very nice bike out of carbon (my daily ride is one), but I think carbon is at its best when it is tailored for its use case, which typically means more higher end bikes.  I would personally skip carbon on lower end bikes as I don't think it provides any advantages as manufacturing and use case coverage dictates that it is often over-built with cheaper layups.  The problem with carbon fiber is that as a consumer you have no visual way of telling whether the carbon fiber fork (or frame or whatever) you are looking at is of a high or low quality, both will typically look identical.


Twenty-plus year old STIs that really and truly have much life left are rare and expensive.
The 7700 STIs are much more serviceable than most, hypothetically. They allow some make-one-good-one-from-two-bad-ones type stuff to be done where it's not practical otherwise. In practice most of them are trashed by now.
The wear parts on pre-Escape Ergo are all replaceable, hypothetically. In practice the world is getting dry of a lot of that stuff.
You ask about derailleur performance in particular. The age per se isn't what matters, but rather how worn it is. A slopped out RD-7700 is garbage compared to a new RD-R7000. Comparing apples to apples, NOS to new, it's hard to get away from giving a subjective answer there in my opinion, but few reasonable people would find anything to complain about either way. 7700 is longer wearing. More reasonable questions would be what are your gearing needs and do you want something closer to period-correct.
The bike is aluminum, 37 years old, and has a 126mm freewheel hub. It's got light construction for its time in terms of tube choice but it also has monster dropouts. If you want to change the group you're buying a 130 wheel, and then you're going to flex its axle and/or add to the already-considerable chance of frame failure. People do all of those things and it can result in a rideable bike. Whether you want to is up to you. You're buying a Campy wheel if you want Campy and Shimano otherwise. Meanwhile the freewheel hub you've got is one of the nicer ones ever made.
If just getting STI on the Klein is what you really want to do and you're more or less happy with the gear range you've got, you could consider keeping the cranks and wheels, getting new 2x8 STIs, a new 7-speed Shimano 11-28 freewheel, an 8-speed chain, a Claris or Sora 8-speed double front derailleur, and whatever pre-11-speed-road Shimano rear derailleur you want. Running 8-speed STIs as 7 is fine and was once condoned by Shimano themselves.
Finally, there are some Kleins that epitomized the 80s crit-geometry-on-everything trend. If your bike is like this, ie sub-405mm chainstays, then getting the FD rub-free can prove tricky no matter what you do with a more modern group.


Where to sleep while touring southern Ontario?

There's an app called Wiki camps which is great for finding campgrounds and works offline.

For free places to camp Community fields can be good. I met a couple guys yesterday who said they have had good luck with firestations, they've not been told no yet when they ask.

There’s also a free camping website which is geared towards RV parking but does have some tent listings. If you google free camping you'll find it.

Lastly Ontario does allow you to camp on Crown land though I'm not sure in that part of Ontario there would be any to be found.


Yes.  Get a new chain.  When I was running Sram Eagle, I found my chain worn out pretty early too, and I also found it made a big difference to change earlier rather than later.
In my experience, this is within the range of normal...on the low side of normal for sure, but not anything that I think you are doing wrong.
Keeping your chain clean is a good thing but not fool proof.
Lastly, I remember reading an article several months ago where several chains were put to the "wear test".  The conclusion was that more expensive chains don't last longer.  In fact someone at a bike shop told me once that the more expensive chains actually wear quicker because they are made with weight in mind.  I don't know if that is true or not.   If I can find that article, I'll add it to the post.
Good luck.


Can I remove the clutch system from bike helmet?

If you mean: is this particular system in this helmet designed to be user removable? Probably not.

If you mean can you remove it and put it back together correctly without compromising its function or safety? Maybe. You could figure out how to dissemble it and photo-document every step.

I'd personally figure out a different way to pack it, as that seems like much less hassle.


Why is standing more common on hills than on flats?

Because in the flats you reach higher speeds, and at those speeds aerodynamics become very important, so exposing more of your body to the wind is a drag.  The standing in flat is then limited to sprint bursts, or just used to give a little rest to your legs and buttock. Whereas going uphill is usually slow so the power advantage you may get standing is worth the trade-off for worse aerodynamics.


Another flatbar to dropbar conversion noob

I think you are out of luck there.
There are expensive cable to hydraulic converters available.
You could get (equally expensive) 10 speed hydraulic brifters and use a 10 speed to 9 speed cable pull converter. This should work with your existing drivetain (you’d have an "empty" 10th gear).
But all of that would be a hack. Is the frame even short enough to be comfortable with drop bars instead of flat bars?


How much of a difference in workout intensity does riding a pedal-forward bike make?

I take it your wife has an Electra 'Townie' style bike with the easy reach to the ground, the high bars and the pedals a little further forward than normal.

Sat down, in the saddle, these bikes do present you with a mechanical disadvantage going up hill as you have not got all of your weight over the pedals. Hence, when going up hill you need to be aware of that, to take a lower gear and inch your way up the hill much like how a recumbent cyclist has to...

...or get out the saddle and pedal with your weight on the pedals as if you were sprinting. Works the same as on a normal bike.

There is also 'easier' handling that is less twitchy but with a bigger turning circle with pedal forward design. So I don't think it is simply a question of workout intensity that you are looking at - ultimately you can put in as much or as little as you wants to...

Many of the 1950's design commuter bikes are effectively 'pedal forward', only when the drop-bar racing bikes with ten speed did the relaxed geometry of a classic 3 speed go out of fashion. You can refurbish an old 3-speed with some modern tyres to get the comfy riding style that the likes of 'Electra' offer.


What is the maximum weight that "normal" racing wheels can withstand?

As a sometime wheelbuilder, I'd say yes. Lightweight wheels definitely come with weight limits and you should respect them. It should be in the manual for the wheel, and ideally on the spec sheet as well.

That's not to say you need to obey them, just be aware that when you don't you're much more likely to have problems. But for a race where they matter, it can be worth it. You're likely to get away with them for flat time trial when a steep climb or criterium will see them fail in the first race. But for the TT, those wheels might shave the critical 5s off your time.

It's not just your weight on the saddle that matters. You're also stronger than a lighter rider, and more likely to have a huge amount of explosive power. Those are the things that actually cause wheels to fail because that's when you're side loading the wheel. Throwing the bike around in a sprint is especially bad because you're throwing your weight sideways at the bike on the down stroke.

I've had customers who can't even get a reasonable life out of standard 36 spoke wheels. All it takes is a 100kg guy who races criteriums or rides to work and likes jumping out of the lights, and their wheels start failing after a few Mm. The tricky ones are the 120kg+ riders who are overweight and are riding to lose it. Often we see them only after their first bike has fallen apart under them (and it's a combination of being heavy and poor technique - they don't lift off the saddle on bumps, so the rear wheel takes the full impact of every lip and pothole). Having to explain that no stock wheel will work can be hard - instead of a $500 bike they're going to need a heavy $600 steel MTB with $300 of custom wheels.


The compatibility info at si.shimano.com is a great resource for Shimano compatibility questions. You can also find the specification handbook (including current models on the web version and pdf archives of the handbook going back to 2004), as well as service documents by model (dealer manuals, exploded views, etc)
The parameters that need to be compatible for a front derailleur are:
Front speeds: triple or double
Top gear teeth: the number of teeth on the large chainring. an FD outer cage plate meant for a 38T will not sit low enough on a larger chainring like a 44.
Rear speeds/chain: different numbers of rear cogs require different chains, and both the width and the profile of the FD cage are designed to match a specific chain. 6, 7, and 8 speeds all use the same chain width.
Shift family: how much cable does the shifter pull? When it comes to switching front shifters, the front drivetrain compatibility chart is not quite exhaustive. I believe all Shimano MTB 3x front shifters pull the same amount of cable, but I could be wrong on that.
Total capacity: maximum accepted difference between big chainring and small chainring teeth count.
Top-mid tooth difference: for triples, how much smaller is the middle ring than the big ring? 3x FDs tend to have some shaping that’s specific to where the chainring is expected to be.
Chainline: distance from the center of the bike to the center of middle chainring, or the average of the chainrings on a double.
Chainstay angle: angle between the line through the center of the  rear axle and the bottom bracket, and the seat tube to which the FD is mounted. Only a concern generally for clamp band derailleurs, and generally only for MTB type front derailleurs. Can be measured directly, found in the geometry tables for a bike, or by referencing the old FD’s specified range of chainstay angles.
Mount type: how it attaches to the frame. Could be a:
-Band clamp: usually includes shims for use with smaller seat tubes
-Braze-on: road bikes, sort of a curved plate on the side of the seat tube, with a vertical slot for the fixing bolt
-Direct mount: mountain bikes, either High Direct/DM, consisting of one threaded hole next to a vertical slot/groove; or E-type/Low Direct, with two bolts a little under an inch apart horizontally
-E-type with bottom bracket plate adapter: older style mtb front derailleur mounted to a plate held by the bottom bracket cup)
Swing/action:
-top swing/low clamp: the derailleur parallelogram swings above the main pivot, generally corresponding to a lower clamp position for a band-type derailleur
-down swing: more traditional style where the cage swings below the main pivot, generally placing the clamp band further up the seat tube
-side swing: instead of a vertical parallelogram, the parallelogram is horizontal; can be had in low, mid, or high clamp band configurations as well as direct mount.
Pull:
Top pull: cable must approach from the top of the derailleur
Down or bottom pull: the cable must approach from below the derailleur
Dual pull: the cable can approach from either above or below the derailleur
Side swing: side swing front derailleurs require the cable to enter from the front, usually with full-length housing along the downtube


How do you know when you need to add more air in the tires?

Look on the sidewalls of your tires, and you should see a recommended pressure range. If your tires are outside that range, you need more air. The lower end of the pressure range is good for soft ground like dirt or gravel or snow, where you need more traction; the higher end is best for roads, and will help you avoid pinch flats.


How hard is it to disassemble and reassemble a bottom bracket?

Any time you see "cartridge" or "sealed" to describe a bottom bracket that means it's not serviceable - you throw it away and buy a new one. Or in some (expensive) cases, replace individual bearing races. The wikipedia Bicycle Tools page has more information. I'm using amazon below to give you an idea of prices.

You will need the appropriate tool to remove the cranks, and another to unscrew the cups that hold the BB in place. Both are readily available but cost about the same as getting new BB fitted. If you want to accumulate tools you could use this opportunity to buy them but it's something that many people decide to get done in a bike shop because it's rare and much easier with a proper work stand.
The problems with a worn BB will be obvious without dismantling anything. If you pull a sealed BB apart it's unlikely you'll be able to reassemble it. The key is how much slop there is in it. If there's too much, it needs replacing. Too much is a judgement call.
The measurement that matters is the spindle length. This is easy to measure once you have it out of the bike but hard to do before then because the cranks cover the bit you're measuring. If you're lucky it will be written somewhere that you can see without pulling it out, but usually the label is somewhere that is inside the BB shell when it's on the bike. Note that they come in 2.5mm increments, so you only need to measure to +/- 1mm.

The easy way is to take it to a bike shop. It's not instant even with the right tools, but you need to apply considerable force to get the cranks and BB off the bike, making it an ugly operation at home. It can be done, but it's not fun. They will pop the old BB out, read or measure the spindle length then try to upsell you from the bottom of the range Shimano BB to however much you're willing to pay. Realistically it's something you'll probably not detect, but the UN54 ones are IMO a good balance between really cheap and just good enough to justify the extra cost (they cost about $US20). You can spend $US200+ on a Phil Wood if you like (they are much shinier).

Also, most bikes come with British BB's, and yours is one of them. Other options are French, Italian and ... read more here (that describes the thread and diameter of the cups).

Edit: one final note. Bottom brackets commonly use both left hand and right hand threads. Again, pedalling the tool forward tightens the part, pedalling backward loosens it. At least with British and Italian BBs, with French they're both right hand threads. French BB's exist to teach us why left hand threads are used on BBs that work.


My disc brake rotors have started to corrode. What can I do?

Generally, it will go away if you apply the brakes a bit (it will be a bit noisy at first, but after a few applications it will look as good as new), since the rust is likely only on the surface (this is one way to tell if a car has been not driven for a few days - rust spots appear on the brake discs, but they'll go away after a short trip around town). Otherwise, if its more serious, you can  try light sanding with sand paper / steel wool / wire brush or something similar and then cleaning the rotor with isopropanol.

It goes without saying, but, don't get oil on the brake rotors while cleaning it.


How to determine what kind of front derailleur can be used on my recumbent trike?

Recumbent / trikes tend to use mountain-bike shifting equipment because they need the extra gear range. While there is a difference in cable pull between road and mountain sets,  front shifters on the whole tend to be much less picky than rear shifters about chain width because essentially  the limit for front shifting has stayed at 3 chainrings (aside from @Criggie with his 4 chainring setup). While it is optimal to try to match the chain width (speed), it is not a necessity. As always: Sheldon Brown

That means you can use pretty much any (Shimano) mountain bike triple front derailleur that fits. The main consideration for you will be how to mount the front derailleur. If you're using a clamp mount, you have to have one that can fit the tube where the derailleur mounts (the 34.9mm in the examples below are the seat tube thickness but many times the derailleur will come with a variety of clamps and shims to match different tube sizes). If you have braze-ons, they need to fit the braze-ons.

The other consideration is where the cable pull comes from (from the top or bottom of the derailleur as it would be normally mounted on a standard bicycle). Many front derailleurs allow for pull from either direction (dual pull) but some like the SRAM below are "top-pull only" or "bottom-pull only."


Inflated tire partially slipped off rim, can I fix without deflating?

Short answer: no.

The only fix is to mostly deflate the tyre (so it's just barely inflated, enough to hold it in place but soft enough that you can manipulate the bead) and work the slack in the bead around the wheel so that you have an even distribution. If you're really lucky there will be a matching place elsewhere that the bead has stuck in the middle part of the rim, and when you push the slack around you'll find that and everything will pop into place. That's the ideal solution.

But this may also indicate that the tyre is slightly too large for your rim, in which case you're better off buying a different tyre. The way to find out is to fix it and see whether it happens again.

When you are fixing this it's tempting to just deflate, push the bead down, and re-inflate. The problem will occur again very quickly. The actual issue is that you have a circular bead that's slighter bigger than the circular bead seat on the rim. If you arrange them so that they're concentric (even all the way round) that will work, but it's not stable until you pump the tyre back up to push it up hard against the rim.

If you have a weird bike with odd-sized wheels it's vaguely possible that this is actually the wrong size tyre altogether. But that's unlikely. More likely you have a cheap bike with slightly undersize wheels, or a damaged rim, and a generously built (cheap) tyre.

It's worth buying a bike pump, not just for times like this, but so you can keep your tyres pumped up which will make riding easier. And it's a step on the way to owning a puncture repair kit (which will save you money as well as time).


How to correctly align "to see" bicycle lights?

Alignment is anything from trivial to impossible. Good lights have a cut-off beam pattern that is more rectangular than circular. That way you can point the light at the road in front of you and not have the central peak that's pointing up into the eyes of people coming towards you. Even expensive lights often don't do this, so you might be out of luck.

The hassle with dyno lights is that you have to be moving to see the beam. I find that getting it roughly right in the workshop than nudging it while I'm riding works best. Having a nylock nut on the vertical adjustment bolt means I can set it to be "just tight enough" and it won't shift while I play with it later. Then I move the light a little while I'm riding - just reach down and push/pull the light a little until it's pointed the right way. If you don't have a locking nut you'll have to stop the bike at that point and tighten the nut fully to lock the light in place.

Actually aligning the beam is a matter of deciding how close to you you want the beam to hit the road and aiming it accordingly. Too close and you have a small, very bright spot right in front of you that actally makes it harder to see than not having the light at all. Too far and you're putting most of your light into other people's eyes. With a circular beam you're going to have light going up, there's no way around it.

My preference is to aim the light such that the top of the beam is just below horizontal. Or with my B&M Eyc that has a nice rectangular beam and sits just over a 406 wheel, actually horizontal. What I do is wait until I'm riding either towards a reflective sign or white wall, or next to a wall. Then I work out where the top of the beam is and push it down/pull it up until it's right. That way I'm getting the light on the road out in front of me without blinding anyone.

That's specific to the type of light and how it's mounted. The only general advice is "make sure it has a proper mount and is installed correctly". Of course, for may lights the answer is "it did not come with a proper mount".

For your fork bridge mounted dyno light the mounts are often cheap steel and if you're lucky there will be a fold or two to strengthen it in places. Those usually end up not working very well.

If the light slips around on the mounting bolt that's usually easy to fix. Get a locking nut and if necessary a longer bolt so you can fit it. The nut you want is deeper than a normal nut and has a plastic insert to make it less likely to come undone. They're cheap, so most bike shops will buy a box of 100-200 for 5c-20c each (more for stainless steel ones) and charge you 20c-50c for one. Your call as to whether $10 for a box is worth it. If you are right on the end of the bolt don't fart round with removing washers, just buy a longer bolt. Most cities have an industrial fastener shop, find it or use an online one (but $5 shipping on $1 of bolts... ow).

Note that the two leftmost brackets in this picture use the curve of the head tube bulge to stabilise the bracket. The other two rely entirely on the bolt being really tight. If you're buying a bracket, try for something like the first two.

If your bracket is bending you need another one. Your LBS or local bike fix crew might have a box of light mounting bits you can go through, and that's generally the easy way. This is where having access to a vice and power drill is helpful, or it's going to be cheaper to get the bike shop to do the work for you. $20 in labour cost is easier than buying a cheap vice and not having any further use for it afterwards.

But, if you have a few tools: Find something that your light will attach to easily and is more or less right to attach to your bike. Or go to a metal sales merchant and see if you can buy offcuts (most sell them by weight), and buy a 10cm piece of angle iron (aluminium "iron", ideally) that you can cut to shape.

Notch the angle iron so you can bend it forward, but don't completely cut off the angled part - you want that there so the light can't be bent too far forward. This is where the cheap pressed brackets fail and you don't want that.

Once it fits the bike and light bend the bottom of the flat so the corners are angled in to fit onto that bulge. It's a little tweak but it makes a surprising amount of difference.


Rather than quoting figures for the right and left flange distances from the Locknut centerline distance, they quote a "flange to flange" distance, along with an offset, for some mysterious reason.

This image: http://issuu.com/novatectaiwan/docs/novatec_hub_dimensions should help translate their "Flange to Flange" and offset figures to be right and left flange distances. In the case of this hub, your left and right flange distances are:

Wl = (F.T.F/2 + Offset) = 36.00mm
Wr = (F.T.F/2 - Offset) = 22.40mm

Using the dt swiss calculator, I calculate 292 and 291mm spokes for building a triple-cross wheel with your selected components.


Buy or rent a bike in Europe for 2 week backpacking trip

Traveling with bikes on international trains, specially in combination with quite a bit of luggage, is not easy.

In most cities you can rent reasonably bikes and going that way will make travel arrangements easier but you can not be sure of getting decent quality bikes that fit you.

For a two week three or more locations trip, I think buying or renting long distance bikes is not going to be worth the effort.
You better decide whether you want a bike holiday, in which you cycle from one place to an other, maybe across country borders or a multiple location holiday for which you use trains to get where you want to go and rent bikes for one or more days in one or more locations.

If you know you want to buy bikes which are available in one of your chosen locations, you might order them to be there when you arrive.
And take them home with you at the end of your travel.
But plan on taking the slower regional trains, with changing trains more often as the fast and long distance trains do not have many or even no bike transport options.
Late July is summer school holiday in big parts of Europe and all long distance trains are likely to be full, needing booking ahead and also the longer runs of the regional trains are likely full and the limited bike space very popular.


How can I store my extra wheels on the wall efficiently, without hanging them by the rim?

While I agree that there are no real risks to string your wheels by the rim, there are a number of DIY and commercial wall mounted racks for hanging wheels at the axle.

Wheelzrack makes one good option, and even integrates a storage shelf for shoes and helmets. They support up to for sets of wheels, which may be a good option in your case.

Feedback sports used to offer a Wheel Arm system, which had a bolt-to-wall mounting option (note: the Wheel Arm is no longer listed on home page but they sell alternate models).  These are designd for shop displays, but will work in the home as well, assuming your significant other is tolerant. :-)

Hope that is helpful.


Front-derailleur bolt undoing: pliers and threadlocker

Just push the cage inward with your hand while undoing the bolt. Use a wad of rag to protect you hand or wear a heavy duty work glove. If you use a pair of pliers you'll scratch the finish.


"Safety levers" are more commonly called "suicide levers" -- they are hazardous to use and make the operation of the regular brake levers more problematic.

A better choice, if you feel you need something along these lines, are "interrupter levers", also called "in-line brake levers" and "cross levers".

https://www.parktool.com/blog/repair-help/in-line-brake-levers


A shim between bottom headset cup and bearing

The custom shim works, I settled with a ~1.4mm option, this was the minimal thickness machinist agreed to make, he said "it would bend in your pocket otherwise". After properly preloading the headset bearings I did not notice any play during pedaling efforts or when applying front disc brake during ~200km the bike made since assembly. That's not much distance, so if anything happens and I survive I'll update the answer.

Apparently, some people experience the same problem.

To get your own shims, find a local machinist and use the blueprint from the question, adjust thickness as needed. My shims were made from a 2024 aluminium alloy plate. The outer diameter tolerance should be in the ballpark of +0mm -0.03mm, the rest doesn't matter.


Can I fix an inner tube if the valve has been pushed inside?

Thanks for the photo! This makes it clearer that your valve body didn’t fall into the wheel rim, rather your presta valve internal valve shaft either fell off or fell into the tube body.

Unlike the photo above, it looks like you have a one piece valve so the core isn’t normally removable (you can’t unscrew the part of the valve pictured above with the words unscrew here) — but if you were to unscrew the thumbscrew too far the inner valve shaft itself  could fall into the inside of the tube.

You’ll need a new thumbscrew at minimum but it might be very hard to get the thin internal valve shaft back up into the valve body properly. Unlike a tube with a replaceable core, I don’t think you can replace the core if you can’t rethread the valve shaft  from inside.

In many ways, it’ll be easier to just replace the whole inner. They are cheap for a reason.


My rear disc brake makes noise when I ride fast

With disk brakes the disk rotor is attached to the hub and not to the rim so a wobble in the tyre is unlikely to be the cause of the noise.

What I'd be looking at is the following:

Are the rotor bolts tight?
Is the rotor warped?
Are the brake pads worn?
Is one or both of the pistons sticking?
Is the calipar aligned properly?

1 and 2 you can check easily.

For 3 remove the pads and make sure that there is at least a couple of mill of braking compound left and that the springs (if present) are in good shape.

For 4, with the pads removed check that both pistons are extended by an equal amount; alternatively with the pads still removed push the pistons back (carefully with a soft implement not a screwdriver) and then squeeze the brake lever, do both pistons move in and out evenly?  Be very careful not to push the pistons out to far! How you sort out a sticky piston is going to depend on the type of brake you have.

For 5 look at the disk rotor as you press the lever, does the rotor displace to one side?  If it does this indicates that the pistons aren't applying equal force to the rotor - this could be a mis-aligned caliper or it could be a sticking piston so you'll need to check 4.


What differs between the Cervelo S5 and S5VWD

They are different frames, with the VWD being lighter than the normal one. It is claimed that other properties (stiffness, comfort, shape) are the same, though.

This thread, in particular the post by em3, point to the following links from Cervelo: a,b.


Front Derailleur Chainring Size Tolerance

According to Shimano front derailleur specs here all road triple front derailleurs support max 50 tooth and have 20 tooth capacity (max difference between largest and smallest rings).

The general consensus on this site is that Shimano is quite conservative in it's specifications so overstepping the max chainring and capacity by 2 teeth will probably work OK.


Suggestions for progressive upgradation of bike

I tried the same approach that you're outlining with a bike I bought (a Shogun), but I had heaps of trouble trying to upgrade components. Every time I upgraded one component it wouldn't work well with the other existing components. I tried to change the cassette but it wouldn't work with my derailleur (even my mechanic couldn't figure out why).

The other problem with upgrading is that each component bought individually will be vastly more expensive than buying a bike with better components in the first place.

So my advice is to live with your bike unchanged as long as you can, saving the money you would be spending on components and then buy a new/second hand better quality bike.


What are the advantages/disadvantages of press fit bottom brackets compared with threaded?

Advantages:

It's cheaper to manufacture cups, even with fine surface finish and reasonable tolerances than threaded shells.
Especially with carbon frames there was an issue with inserting threaded shells which needed to have perfectly parallel faces. With press-fit cups and cartridge bearings having some factory loose, the tolerances are not so strict.
A press-fit bearings are just a bit quicker to install. The difference may not be huge, but is significant when assemblig thousands of bikes.
Removing a threaded bottom bracket after a few years can be a daunting experience. Especially when no grease/thread glue was applied and it was mounted on a steel frame.
Thread could easily be damaged when replacing a bottom bracket without care.
A new standard is always a good opportunity to use for the advertising department.
Although sometimes recommended, no tools are usually needed for installation.

Disadvanteges:

Press-fit connections wear out more quickly when you replace the bearings often.
Bearings which have to account for imperfections in cup mounting, don't last quite as long.
It is possible to re-thread a damaged bottom bracket shell thread while it would be way more complicated to replace press-fit cups.
Bearing removal requires care and experience to protect cup surface from damaging.

There are more diferences, but they are more specific to a given type of bottom brackets, and the ones above are more general. Most of the advantages of press-fit are felt by the manufacturers rather than users, although I do appreciate the ease of installation of these bottom brackets.


How to remove pedal bolt with round, smooth head

I expect that when you try to turn the nut you'll rind that the round bolt head is eccentric on the bolt. Side on it looks like the sketch below, and means the bolt won't rotate once it's in the hole.

This is quite old school, and they're very easy to manufacture with only fairly basic hand tools. Imagine trying to cut a hexagonal hole into a pedal using only a drill and file.


It is a machine used for heating the shoes so that they can be formed to your feet. the shoes are heated. You then put them on your feet and they use a vacuum bag around the shoe to compress it against your foot so it gets the proper shape. Here's an article that explains it. I've had something similar done for hockey skates, although without the vacuum, and the result was quite comfortable skates. Hockey skates are quite hard, so I could see this being necessary to get the right shape. Cycling shoes are often rigid, at least in the sole, so I could see it helping with fit.


Generally you'd take the fender off a bike, put it on an anvil, find the right place on the horn of the anvil that matches the radius of the curve, and bang out the ding. Then you'd buff out any scratches or rechrome it.

(this anvil's horn is upward curving, you'd want one with a downward curve that matches your fender angle more).

You don't need a big huge anvil, there are hobby anvils that are much smaller. You do want to choose the right type of hammer (most likely bronze faced) so that you don't scratch or mar the finish too much.

You can  also take it to an autobody shop or a metalworker and have them do it for you.


The idea is to wrap them so the friction against your hands when riding tightens rather than loosens it. I find I have to swap the direction of wrapping as I go past the shifters. Start at the bar ends and go "up the inside and down the outside" (cw on right, ccw on left). If you do an extra loop around the shifters you can change direction for the tops.


Could a flat tyre two days later be due to a clumsy service?

To me, this sounds like coincidence. If the shop had punctured the tube and caused a leak, I don't think it would have held air for two days before showing any signs of going flat. Especially given the fact that you reinflated the tube and it went flat again by lunchtime. The leak is fast enough to make the tube go flat in just a few hours, so it seems unlikely that the tube would be OK for Tuesday and Wednesday and only start leaking on Thursday. When replacing the tube, you should look for the cause of the leak. You might be able to find a foreign object that caused it, but it's possible you won't with a typical puncture. If you find the side of the tube leaking, that might indicate that it got pinched by the tire during installation


I'm going to see how many answers I can say this in today - don't overthink it.
A 100mm full suspension 29er is going to be able to shred anything you can throw at it for a long time. That's a good amount of travel to start with, and on a 29er it's going to feel like even more while staying efficient. The epic has a really well balanced geometry as well. It's not too twitchy, and it's not so slacked out that you have to fight it through twisty slow stuff.
Full squish 29ers are great 1st mtbs because they are so versatile. Plus if you end up really enjoying mtbing, then believe me, you will end up owning more than one bike down the road so don't sweat your decision- you made a good one.
While you own the one you have, swap with buddies, go to demo days, take advantage of opportunities to ride different styles of bikes instead of just guessing what type you think sounds good for your next purchase.
Keep in mind that everything is a trade-off. More mm of travel equals more fun to point down technical descents, but less fun to get there, and less precise handling. Heavy big squish bikes can be really taxing for riding cross country, which I'm assuming is what you'll be starting off doing.
Regarding your 2nd question, you can safely go up 20mm in the front (fork) although it will slack the geometry out a bit. The RockShox Reba that came installed on that bike can be converted to 120 by removing a couple of spacers inside the fork (it may only be 10mm of spacers that can be removed in newer models, ask your dealer). As for the rear shock, that's a bigger can of worms that you probably don't want to open.


How can I increase my speed on my hybrid bike?

It really depends on how you're lagging.  If it's because of feeling tired keeping up with them then reducing friction might be an option.  I'd suggest that the most likely reason for lagging behind is that there is a fundamental speed difference though.  See whether you're having to pedal faster than them to keep up.

Your top speed is governed by your cogs.  Take a look the number of teeth on the front and back.  If you have a 13 tooth smallest cog on the back you could get that cassette replaced with one that starts at 11 teeth.  Up front you're probably running a 46 tooth chainset whereas your road bike friends are probably running 50 teeth.  Again, you can replace that if you fancy it.  Just be careful if you do make it faster that you don't lose the low end you want for getting up hills.  You should be able to get quite a decent range with the right set of cogs.

Reduced drag from narrower tires may reduce the friction allowing you to accelerate more easily and maintain speed better but won't affect your top speed appreciably.

Clipless pedals may allow you to improve your efficiency with pedalling.  I would only look at these when I was happy with a bike though, rather than as a solution to a problem like that.

Update:  Based on zenbike's comment I'd say the switching to a road bike warrants more consideration.  Assuming it is the gears he's right that a hybrid may well be difficult to alter to run the gear ratio you want to keep up with your friends.  When thinking of getting a new bike take a look at how similar it is to the ones your friends ride.  Simply getting a cheap heavy one if they have light racers may well leave you with a similar problem.

If 2 bikes have the same gear ratio but one is heavier it will be able to go as fast, but it'll be more effort to get it up to speed, and a little more effort to cruise at the same speed.  It's less of a problem than not having the right ratio, but you'll probably find your self lagging a little at first.


My hydraulic Hayes brake lever comes down and clicks, and it doesn’t retract?

Either the mechanical linkage to the piston is broken - which would explain the lack of return force, but if the lever is not loose and appears to be pushing the piston then the problem is in the hydraulic system.

The lever not returning indicates you have a bigger problem than just needing a bleed. If you lost substantial amount of hydraulic fluid you should be able to see a leak.

I think you have no option but to take it to a good bike mechanic for diagnosis and repair, or replacement.


How much more expensive are hydraulic disk brakes compared to mechanical disk brakes?

It depends on wether you are talking about disc brakes on a drop-bar bike or disk brakes on a flat bar bike. Hydraulic disc brakes with integrated shifters (on drop-bar bikes) are pretty expensive. Generally I made the experience that for the same price you can get a flat bar with hydraulic or a drop bar with mechanical (e.g. Bulls Daily Grinder 1 vs Canyon Commuter 5.0).

On flat-bar bikes the difference seems to be fairly small when comparing hydraulic vs mechanical disc brakes but this varies a lot, since there are also mechanical and hydraulic brakes of vastly different quality.


100 x 1.34 x 1.34 = 180.
With three gears you've got a starting gear (100%) and then two change-ups of 34%, leaving you at 180% of where you started.
You'd probably find similar sums work for the other two examples you gave.


Can a BB30 Crank Arm (Left) power meter can be used with a BB386EVO Crankset

The first two you list are BB30 arms and will not be able to work on a BB3860EVO spindle. BB386EVO and other "long-spindle BB30" left cranks almost by definition are going to have the flatter profile of the third one and not flare out like the first two. They would go on the same frame but with the BB386EVO there would be an external cup in the way taking up that space. If it's any of these it's the third.

The third one looks like it probably would work in terms of physically being able to bolt to the spindle, but one frustrating thing about where we're at with these kinds of cranks is that FSA has never actually come out and said, "Hey, all our 8-lobed 30mm spindles interchange with all the 8-lobed 30mm left cranks for a sound connection." So given that your crank model doesn't appear in the compatibility list for that version of the power meter, it's kind of no guarantee.

The other thing is that even if the spindle interface compatibility is likely to be fine regardless of what the compatible model list does or doesn't say, the same inference can't be made that you're going to wind up with an exactly symmetrical Q-factor, although it would likely be very close.

You really should contact FSA with this question before you buy. They're the only ones that can answer questions about cranks such as this that are a few years old and don't show up in their public-facing documentation. Also the model number is that CK-OS6020/86/79.


My method for measuring ERD is simple for a normal wheel or a deep section aero wheel.

Feed a white or light-coloured string through two spoke holes directly opposite each other.  Count the empty holes on either side to be sure.

Then thread a nipple onto the string on one side.  Knot string behind nipple and pull string so it sits in the proper place.

On the other end of the string, thread enough nipples so that the first one pokes through the rim and sits normally.

Use hand tension to take the slack out of the string, but not so much it stretches.

Use a permanent marker to dot the string where it enters the second nipple.

Release it all, and then measure from the knot to your dot, and add the height of one nipple.

Note if you have access to the base of the second nipple then dot there and don't bother adding an offset of one nipple height.

Then repeat this in two more places around the rim - bare rims can be quite out of round, so averaging three results should get you a more accurate number.


Will a 11-speed cassette fit my Giant SRC 3 frame (~2007)

Presumably you are planning to upgrade the older frame to a newer complete 11 speed groupset. Makes sense as 105 rim brake groups are relatively inexpensive now.
In 2007 11 speed road groupsets didn’t exit, so we can assume your Giant had a 10, 9 speed or less groupset, and a 10 speed or less compatible hub.
When 11 speed groups were introduced the width of the splined free hub body on the hub was made a little wider to accommodate an extra sprocket. This means 11 speed cassettes will not fit on your hub, so you need new wheels with an 11 speed free hub body.
However, some wider range cassettes can overhang the inboard end of the free hub a little and will fit on a 10 speed hub (a spacer is used on an 11 speed hub), but of course you need a long cage derailleur to work with the wide range cassette.
FYI, frame dropout spacing didn’t need to get wider for 11 speed groups, still 130mm for rim brake setups.


Is Sram PG850 cassette a substitute for Shimano TZ31 freewheel?

SRAM Cassettes are compatible with Shimano Cassettes, but a cassette and a freewheel are different components. You will not be able to use the SRAM Cassette to replace your Shimano Freewheel. You will need to replace your freewheel with a freewheel.

The difference between a cassette and a freewheel is that a cassette is just a bunch of cogs that slides onto a free hub. This allows the wheel to spin without the chain moving. With a freewheel, the cogs and freewheeling mechanism are all in a single assembly, and this is screwed onto the hub of the bike.