What year etc is this Specialized Epic Comp?

The nice people at specialized.com have a archive section with pictures of all the models produced since 2008.  Go to the web site and scroll down to the bottom of the page. There's a Support section with Bike Archive as the last item.

Answer shamelessly stolen from here.


What would be the best bike frame to build a gravel bike?

When I was considering building a gravel bike from an older frame I considered two basic frame types: cyclocross and drop bar commuter.  A light touring bike frame would be a good basis as well, although many older touring frames were built for stronger 26" wheels.

The primary features you are looking for are cantilever brakes and clearance for at least 32mm preferably 35mm or more tires. Another is possibly the ability to mount fenders, which you will find on a commuter or tourer.

Steel seems to be the material of choice for durability and comfort, but if you value light weight Al can be made to work. It really depends on what compromise you want to make.

In terms of geometry take your pick between more aggressive cyclocross or more relaxed commuter. One thing to bear in mind is older cyclocross bikes predominantly have a 'Euro-style' high bottom bracket.


Massive loss of pressure in my front tire but it still holds air

A tube is a sealed system.  If the rubber isn't punctured and the valve is closed, there isn't anywhere that air could have gone all at once like that.  The only thing I can think of is maybe you do have a small blowout tire side, and somehow the tube is sitting flush against the tire in such a way that it's holding it closed for now.  May be worth taking the tire off and checking the tube itself, being prepared to replace it.  Because(in the one in a billion chance that this is what happened), if that did happen, it could be hazardous to keep riding on it.


You can't just take a cog off a 10 speed cassette and put it on a 11 speed cassette -- the big one is attached to the spider, so you can't really remove it and use it to build your own cassette.

There are a few options (choose one):

Use a Wolf Tooth RoadLink to mount the derailleur lower and use a bigger cassette
Use a slightly smaller front chainring (46t or 48t)
Do a cage swap from a long cage mountain derailleur
Move to SRAM shifters and derailleurs or a lower speed Shimano group (10 speed?)
Use a JTek Shiftmate 8 (or 8A, preferrably) and a Shimano 11 speed mountain derailleur and a bigger cassette
Use bar end shifters and a different derailleur
Just try SRAM's 11-36 road cassette and see if it works by adjusting the derailleur (linked article claims putting the B-screw down 2/3rds of the way makes it work fine on an Ultegra).

I'd probably start with option (7) and failing that, opt for option (1) or (5). Other Shiftmate configurations are possible with different cassettes (e.g. 11->10 speed and then handling derailleurs+cassettes appropriately).

Note that a 50/34 + 11-32 already gives you a pretty large range, provided you're shifting correctly.


What to consider when changing V-brake for a disc brake?

First, it's an expensive upgrade that won't benefit you much. You'll see quite a few cheaper bikes that only have a disk on the front, because that's where you get most benefit from a disk. So the cheaper option is definitely to buy a better V brake. It will work just as well and be cheaper.

You will need a new rear hub, and it's likely to be cheaper to buy a prebuilt wheel rather than pay someone to rebuild your current rim with a new hub into a wheel (I suggest not re-using the spokes even if you can). You will, of course, need to buy the disk brake as well.

Since it's the rear brake, I'd go with the cheapest cable operated brake I could find. The advantage there is that it's cheap. A more expensive cable operated brake will work slightly better and have both pads adjustable making it easier to set up. But it won't look any more like a disk brake, so there's no real benefit in your situation. Likewise, a hydraulic brake will work better in the rain and snow, but cost more.


Since hybrid bikes may be a compromise with no benefits, why are they still often preferred for commuting instead of drop bar bikes?

Simply, I reject the premise of your question and I'm sure I'm not alone. I say that as someone who has a tourer and a hybrid, and commutes on both - the speed difference is much less than the variability in traffic volumes.

In practical commuting conditions you're rarely aero-limited anyway, rather it's the speed of traffic, and to a lesser extent the acceleration. The extra visibility from the more upright position can mean getting away from a junction a touch sooner than in a lower position.

The biggest aero benefit from drop bars is when riding in the drops - and you don't often see people commuting in the drops. That position is much more useful for sustained effort than the typical stop-start commute.

Hybrids generally have a sufficiently forgiving fit that you can buy nominally the right size, get the saddle height right and go. No hassle, no need to be particularly flexible. Most commuters won't have heard of the concept of having your bike fitted properly, and would rightly have no interest in it.


How to use SKS multivalve adapter with dunlop valve?

The DE Valve, or Dunlop Valve, is the same size and thread as the presta valve, at the tip.  However, the length of the valve where it is the same diameter as presta valve is much shorter.

Pump heads which rely on the compression of an o-ring to attach to the valve, especially with multi-valve heads, often do not find enough surface area on the DE valve to stay attached.

There is no good solution to this problem, aside from changing the pump head.


Adjusting derailleur with bike upside down, is it ok?

Turning it upside down seems to make the most sense, assuming it can be easily balanced. Derailleurs work by spring and cable tension, not gravity, so there should be no problem with working on it with the bike upside down. The only issue you're likely to have is reaching the shifters (assuming they're bar-mounted). Also, if your bike has disc brakes, you should check out this post about potential risks of inverting the hydraulics.

I pretty routinely will invert my bike when working on it, as I also don't have a workstand, and it's never caused problems before.


Individual cassette gears and swap a 10 speed for a 9 speed

A long time ago some bike shops stocked single cogs, but that was when there were 5 speed cassettes and few choices. Back then few people seemed interested. Today with 6,7,8,9,10,11 speed options, three major manufacturers, often with multiple materials in each width as well as other variations, there would be too many options. I suspect even the really big online shops would struggle. For comparison, look at spokes - few places stock more than the most common types in the most common sizes, let alone 2mm increments from 100mm to 400mm (Rohloff 16" wheel to front 36" wheel)

Think about what's required: you want a replacement cog for the particular cassette you have, out of at least 10 options for your particular combination of manufacturer, number of cogs, material and cost. Sure, you would probably accept a cog out of the next step up or down in the manufacturers range, as long as it was compatible (hint: it probably isn't).

Look online: Wiggle have 84 cassettes listed, ChainReaction have 69 MTB and 56 road cassettes, Starbike have 80 options. Assuming they average 9 cogs per cassette and 20% are duplicates/compatible, that's over 400 different cogs to stock.

(too long for a comment).


Well, it depends a lot on the specific model of bike, and likely even on the exact frame size.  You can probably eyeball it to get a good idea.  Remember that larger tires are both wider and stick out more from the wheel.  On a road bike, odds are high that you can put a slightly larger (say, go from 25mm to 30mm) tire but not a hugely larger tire.  If you want to make a big jump you probably also want to get wheels with a wider rim. Note that for off-road tires, the knobs aren't usually counted in the mm size but definitely do affect whether or not the tires fit on your bike.

Look for:

Front and rear: Brake clearance — can a larger tire fit in the brakes? If this is the only issue, you can get different brakes
Rear: Stay width — will a wider tire rub on any of the stays (rear)?
Rear: Stay bridge clearance* — will a larger tire hit the bridge between seat stays or chain stays?
Rear: Seat tube clearance — many bikes have a geometry where too large of a wheel/tire will hit the seat tube above the cranks
Front: Fork clearance — how much room is there under the fork crown? (height and width)
Front: Down tube clearance — how much extra room before the front tire hits the downtube?


There is one thing you can try, if you have disc brakes. It works a lot better than one might think. You can put zip ties around your tire and rim if there is enough clearance. The more zip ties the better the traction. Also the heavier duty zip ties the better. When placing them alternate the heads so that they are on both shoulders of the tire.

I have ridden on ice and snow several times with this method and have yet to go down. I wouldn't get to crazy on them and it helps to keep a pocket of ties, but this method works and does not break the bank like a $100+ studded tire will.

If you can lower your tire pressure slightly that will help as well. I have run this method on a 26" MTB tubeless, running 15psi and it never slipped on a parking lot covered in 1" of solid ice, that i had trouble walking on.


Are the holes always on the tread side of the tube?  Do you often go over curbs or other large bumps with the bike?  The possibilities are:

you're damaging the tube when you change/patch it
you're running over a lot of thorns/tacks
you're getting "snakebite" flats from running the pressure too low
someone has it in for you and is "helping" the tire go flat

In any event, for that much weight on a road bike 60psi is the minimum you should be running -- I run 90-100 on my 700C-35s.  You should get Kevlar-belted tires -- much more puncture resistant -- and get tires that are rated to run at least 80psi.  And I'm wondering if 35s aren't a hair wide for 19 rims -- that may be contributing to snakebite punctures.


The noise was coming from the seat post. Removing the dirt, reapplying some grease and re-tightening the clamp solved the problem. I have also identified that the seat clamp is kind of broken, and the saddle was not leveled.

Thanks for the comments, I didn't know that noises coming from the seat post were that common.


Modern suspensions have a valve inside, and when the suspension moves, the valve moves inside oil, and the oil is forced to pass a very narrow opening.

The size of this opening is different depending if the suspension is compressing or returning. Usually, there is a spring which lets the oil flow more when it compresses, and less when it rebounds (the spring closes the so-called lip-valve), thus damping the oscillations and giving the rider more comfort and control.

Then on these modern suspensions, there is a knob that shuts the valve close, so that is impossible to compress the fork at all (some models), or the suspension locks close to the bottom and keeps some of its travel (some other models), and so on.

The blow-off feature is one that allows the system to auto-release when you hit a very hard bump, because the oil pressure rises so much that it activates an auto-release system. Some extra-super-fancy models allow you to adjust how hard the hit needs to be in order to release the lock.

As far as I remember, some cheaper models have mechanical locking system, which lock the suspension the same way you lock a door (some metal slides inside and blocks the suspension), but this might be considered a not very elegant solution.

Remote lock means the knob you turn is mounted on the handlebar, so you can activate it without taking your hand from the handlebar. I guess this is actually NEEDED only for high-end mountain-bike racers, but you know, mountain-bike is a very fashion-oriented activity...


There is no such thing as 'your' bicycle seat tube size, except as a very rough approximation. Bikes of different models and from different manufacturers that are specified as the same seat tube length say can actually vary quite a lot in size.

Seat tube length is a poor sizing system, and only really works to differentiate frames of the same model. This is why many manufacturers just use small, medium, large etc. The stack and reach system is much better, but somewhat hard for new riders to figure out an make use of.

All of that said, a 54cm bike sounds a bit to big for you. All of the bikes I've had are 54 or 55 and I'm a little taller than you.

Advice that is repeated by this community again and again is that you have to try out bikes for size before you buy. If you are buying from a local store, let the sales staff guide you. If you are buying used from private sellers you'll have to do a little research on bike fit and always do a test ride. If you are starting out and considering buying mail order from an Internet site - don't.


Shimano Hollowtech left crank arm getting loose

Thread lock will help hold the bolts on. I would apply it to the bolt thread, and not the actual crank arm thread. You will need more force to remove them when you do come to remove the crankset. But they shouldn't need any more strength to put them on. Just tighten them to the recommended torque setting (it should have it written on the crank arm).

Fundamentally though, it sounds like you have a few problems which only a new crankset and BB would solve.

I got a Tiagra Hollowtech chainset on ebay for around £30-£40. It might cause more harm than good trying to threadlock it all together, and give you more problems when trying to get it off and replace it later down the line.


Can I use a Shimano 105 10 speed BCD 130mm 52t chainring as a replacement in my 9 speed tiagra triple crankset?

Should work fine, assuming the BCD on the 105 52t chain ring is also 130 mm (and not 110 mm - compact).  The 105 chainring will be profiled ever so slightly thinner for the 10 speed chain, but will not affect 9 speed performance. Make sure to orient the new ring in the correct position with the small metal tab (that catches an errant chain)  pointing  toward the crank arm.


Oil it.
Your main hinge is a permanently assembled pin.  It is not a bolt and should not be removed.
I also notice your bike has rust marks - so I guess it has a hard life and is stored outside.  This will absolutely contribute to difficulties opening and closing the main hinge as well as shortening the overall life of your bike.
Are you following the recommended maintenance?  I expect it would say something about lubricate at least yearly, and more often in harsh conditions (like outside storage)


rear shifter lever gets stuck when shifting gears

This is not easy to solve without actually having the bike to play with. It's also something I'd do fairly quickly so I'm trying to give a detailed explanation of something I've learned to do from experience rather than written instructions. I've built my own bikes, worked for a year as a mechanic, and ridden rather a lot on a variety of different bikes. I'm also regularly wrong and still learning. So...

Modern derailleur systems have a lot of things that have to be adjusted fairly accurately for them to work properly. Unfortunately some of the tests that a mechanic will do are destructive, in that they will usually cut the gear cable and replace it. Generally speaking for anything more complex than tweaking the barrel adjuster they will replace the cable and outer, because those are often the problem and they're cheap. In other words, paying $5 or $10 for a new cable+outer will often save $20 or more of mechanics time.

The other thing is that a cheap shifter like yours is only about $20 to replace, so often a shop will just put a new one on and not bother trying to fix it.

Leave the cover off the shifter (as it is in the photo), everything should still work. If you lost that cover in the crash, buy a new shifter (or replace the cover if you can somehow find a matching one). The missing cover isn't a problem in a nice clean shed, but on the road the shifter will fill up with water and muck and stop working fairly soon.

Any of these steps might fix the problem, but in order this is what I'd do:

Look inside the shifter, jiggle the bike, trying to see whether there are any loose parts in the shifter (or random debris). Note that it's full of sticky grease so anything loose will likely be stuck in place by the grease.
Try to work out what everything does, and whether anything is out of place.
If you find something, try to work out whether it broke off the shifter (and if so, whether it's important), or whether it's from the outside. Then remove it.
inspect the cable and outer between the shifter and rear derailleur. If there are kinks or damage that will probably be the problem, and it's the thing to fix first.
Next, get slack gear cable next to the shifter. Often there will be open sections of cable and you can pop a section of outer off the bike to get this. The attachment to the frame looks like this, although they're usually welded on rather than riveted:
Now you can pull the cable to make sure it slides freely in each section of outer. If it doesn't , replace it. What you're looking for here is not "maybe a little extra friction" but "hard or impossible to move by hand".
The shifter. Look for obvious damage. Hopefully you did that already :) Specifically, if the release lever that's not returning is bent it might rub on the body of the shifter. Even plastic levers do this.
If there's abrasion on the plastic at the join between lever and body that can also produce this effect, and carefully trimming away the damaged plastic along the join can sometimes fix it.
Click through gears. Without the derailleur pulling on the cable it will only shift into the lowest gear, but it should do that easily.
Pull gently on the cable as it leaves the shifter. You're just reproducing the pull from the derailleur spring, not ripping the shifter off the handlebars. Now click the other lever on that shifter to change back up through the gears.

It sounds as though the last step is likely to fail. If so all you can do is poke around in the shifter more aggressively, trying to dislodge anything loose, maybe put a bit more oil in there to looses the grease and see if that helps.

I'm sorry this is so non-specific, but in my experience the "generally poke it and lube it" approach works about half the time, and the rest of the time the problem is a damaged part that can't be replaced because no-one sells parts for cheap shifters. In the shop I worked at we had a box of old shifters for times like this and if the customer couldn't afford a new one we'd try to find a second hand one. But that saves $10 on a bill that's already got over $50 in labour costs on it.


Are these extra holes on the frame for disc brakes?

You’ll find similar decorative holes on the opposite side, which is an indication that they are not for disc brakes because those get mounted on the left hand side only.

The holes are mostly through quite a thin section of metal, recessed, which is probably too insubstantial to do anything useful, so no disc brakes.

The ‘Street’ model comes with mudguards and a rack ready mounted through the lower hole, which you’ll see is in a place with thicker metal and presumably the hole is threaded for this:


Correcting An Inverted Recessed Mounted Caliper Brakes On Vintage Bike Frame

I believe they did it this way since it takes a right-angle drill otherwise.
The clean way to do this is just use a front recessed mount brake and install it non-recessed. In some cases one can also find and transplant pivot bolts to make this work. Here since the back side has now been drilled, it would be easy to imagine problems with the brake slipping around if the recessed nut wasn't where it is. Conceivably you could take up the space with something else, maybe an aluminum presta grommet, and then put a front on it. Unless the looks are really bothering you, leaving it is probably best.


Replacing Giant Defy 4 2013 alloy steerer fork with Giant carbon steerer fork

As other have stated you should be able to use the old headset providing it is in good condition. If you are swapping forks due to an accident then replace the headset even if it feels smooth. Your alloy steerer likely used a "star fangled nut " to apply the headset preload. With a carbon steerer you need a expandable plug that is made for use with carbon steerers.


For a single gear ratio turning at a constant cadence (revolutions per minute of one pedal), a larger wheel diameter will have traveled farther/faster. A larger wheel would increase top end speed, a smaller wheel decreasing it.

Gear ratios are gear ratios. For a given chainring tooth count moving at a given cadence, the smaller the gear in the rear the faster the wheel will turn. The larger the gear in the rear, the slower.

Basically, if you took a road bike that was designed for 700c wheels, and put 20" bmx wheels on it, it would be slower at a given cadence in all gears. The opposite would be true if you could increase the wheel size.


Are 26" racing wheels still being produced?

Quick answer is yes.

http://www.zipp.com/wheels/404-650c-tubular

http://www.corima.com/boutique/default.cfm?basketAction=add&reference=161102
 - if that link doesn't work it is for 650c Corima Wheels.


How much aerodynamic drag does each component contribute?

I believe this is a hard question to answer because there are many interactions between different parts of a complex shape like a bicycle and rider.

At a guess, I'd rank components by frontal area and position toward the front on the bike. For instance the rear wheel has less effect that the front wheel  because it is moving through disturbed turbulent air.


Disc brakes and single walled rims - is there something to worry about?

Well, let's compute the forces. For example's sake, I'm assuming 80kg of bike + rider, all braking force on front wheel and deceleration of 5 m/s^2 (extreme, but possible). This equals 400N at contact surface. The radius of 559mm rim and tire is something like 320mm, giving 128Nm of torque. The spoke hole is at 22mm radius, and cross 3 lacing places the spokes roughly tangential to hub flange. Using the axle as pivot and spoke attachment to hub as lever, we can calculate that we need force of 5818N to produce the torque.

Spread over 32 spokes, that is 181 newtons per spoke. Since spokes in a properly built wheel are already at 1000N or more, the increase is around 15-20%. This requires a rim with stronger spoke holes, but not by that large margin.

Keep in mind, that in many double wall rims the spokes attach to outer wall. In this case, the extra wall doesn't help at all.

The case with radial spokes on both sides is different: The spokes exit the hub at zero angle, there is no leverage and if the spokes wouldn't stretch and let the hub twist, the force would be infinite. Calculating the actual force is left as an exercise to the reader :)


Biking to the airport / leaving a bike for a week

This isn't uncommon in our neck of the woods. If you're a light packer, taking your bike the the airport can be a huge money saver.

If your airport doesn't have a bike locker, bring two trusty u-locks with you. Use one u-lock to secure your front wheel and down-tube to one pole, and the other u-lock secure your rear wheel to another pole (please, never use a cable lock unless you're hoping to file an insurance claim for your bike when you get back into town). Try not to use your favorite bike if you have more than one.

Either leave fancy accessories and lights at home or take them off and take them with you when you arrive at the airport.

If your seat post uses a quick release, I would recommend replacing it with a bolt-on clamp. This won't guarantee your seat (or other bolted on parts) is safe from a well prepared perpetrator, but the majority thieves are looking for a quick and easy score, and will skip over your well-secured components in favor of lower hanging fruit.

(photo borrowed from lifehacker)


Can you use shimano m8000 replacement cogs to replace Sunrace mx80 cogs?

While this is not a definitive answer it may help with your decision. If you look closely at the mx80 you can see that some of the teeth on the larger cogs have some extra machine work (notches) done. These areas are to facilitate the chain moving from one cog to the other. For optimum performance the "notches" must be correctly aligned. The variation in the width of the splines on the freehub make this alignment foolproof. Looking at two 9 speed cassettes in my parts bin, the indexing of the notches on the cog and its position on the freehub is not universal between all brands. What this means is that while the cogs may fit, shifting  performance may not be optimized.


50km/h = 13.9m/s = 833m/min. Wheel circumference is roughly 2m so that the wheel is spinning at 417rpm. Sealed industrial bearings easily withstand 10.000rpm and more. The steel ball bearings inside even more.


Fixed gear Biking, how to ride properly?

Put a front brake on it if you're using it on the street.
Don't get distracted and forget to keep your legs turning, this comes with practice.
Watch out for pedal strikes in tight fast corners, not sure how you can practice this safely.

Other than that, it's just like riding any other bike.


How to check and ensure parallelism of front derailer and chainrings?

It depends on the derailleur.
Most or perhaps all Shimano FDs intend to have you use the top forward part of the outside cage as your reference surface. Where the logo is. Their published procedures show this. This is especially true of the knuckle type road models of the last few years.
SRAM Yaw FDs have you use the marked lines down the center of the cage in the back and front while looking down. Other SRAM ones use the same forward top surface.
Sometimes you don't know and have to intuit it. Usually you should avoid looking at the inside cage as your surface because it's typically stamped and manipulated all over the place. There are of course FDs, usually older, where the sides of the cage are parallel, but usually those are easy to align. (They're the sort most likely for you to need to angle the cage.)


Can I replace Shimano 105 5500 shifters and derailers with new Sora R3000 ones?

Can I start by switching out the shifters and derailers with new Sora R3000 parts (also 9 speed)?

All Shimano 9-speed parts use the same derailleur pull ratio (except the front derailleur pull ratio can vary between MTB / road components). Thus, you don't even need to change the derailleur, just changing the shifters is enough.
The STI levers are short-pull levers compatible with any cantilever or caliper brake. They are not compatible with V-brakes. As your old STI shifter/levers were short-pull too, no changes there.
Just be sure to select the Sora 2x9 parts instead of going for Sora 3x9 parts.
I'm not sure what issues you have but as the STI levers are expensive, please be sure to eliminate the possibility of issues coming from some other parts first. Perhaps your bike needs new inner and outer cables instead of needing new shifters?


Campagnolo brake, closes unsymmetrically

In the very last image of the video there appears to be a small screw hole in the caliper. Looking from the right side of the bike it is behind the exposed cable, between the adjuster and the cable clamp. That screw will adjust the spring tension. Turning the screw "in" will increase the tension on the spring. The increased tension will delay the brake movement relative to the other side. Based on your video I would think you need to back the screw out. Start with 1/4 turns. As others have commented if you can't adjust the issue away it may be time to strip them down and clean and lubricate the pivot points.


What are the effects of different types of rear shock installation on full-suspension bikes?

The good folks at Bike Radar have already covered this in pretty good detail in a two part article:
Part 1 and Part 2

There's also a chunky thread on the Pinkbike forums that has pictures and descriptions of loads of different setups:
Pinkbike - Basic Full Suspension Types / Reference With Pictures

In regards to price, it is not the suspension setup making the difference, it is the quality of the components.


Symptoms of handlebars that are too narrow? Triceps pain?

I went from 42cm to 40cm bars on a road bike and experienced the same symptoms.  The switch to narrower bars can definitely cause tricep pain at the elbow.  So, yes, tricep pain can be a symptom of narrow bars (it could be from other things too).  Whether it is a temporary or a permanent symptom can be gleaned by how you feel after you've had some time to adjust to your new setup.

It sounds trivial, but make sure when you are riding in this new cockpit, that you keep your elbows bent and use your arms as suspension/dampening/etc.  If you aren't able to ride comfortably with your elbows not locked out, this is a problem.  If this is the case, I'd first add some rise to the stem to bring the bars up a bit.  If you still can't get a comfortable position, then I'd recommend getting another set of 42's and riding what you know is comfortable and works for you.


In such cases, I often check ebay or similar marketplaces for a used/best offer/parts only item to scavenge the needed part from. One often needs to be patient and make multiple offers before succeeding. As far as compatible replacement parts, si.shimano.com documents may indicate compatible parts if you haven't checked there yet; alternatively, a local bike shop employee might know what works and where to get one.


Installing mechanical group set on "electronic only" frame

I have a solution for you (if you haven't got the electronic groupset already), inspired by road bikes from '70s and '80s era.

Namely, the rear brake cable on the top tube.

on some of those bikes runs through the large eyelets through a very lengthy outer cable (the eyelets merely hold the cable in place):

while on others there are two cable stops near the ends of the top tube and the inner cable is visible:

Now, if you do the same with your derailleur cables, namely run them through lengthy outer cables, the force required for shifting is in fact exerted only near the brifter and the derailleur itself, thus places prepared for clamping.

The only question is whether the outer cable stiffness (in length) is high enough to assure shifting accuracy.

  I don't own the pictures, they are purely for illustration.


How does the new Canyon Endurace rim version support 33mm tyres with R7000 brakes?

I talked to Canyon's support and they have clarified that apparently it's an error.


If the cranks are prevented from moving at the same place in their rotation, they are most likely catching something on the frame, rather than the problem being with the gears or chain.

Some basic troubleshooting you can do:

Hold the bike of the ground, slowly turn the cranks forward and backwards by hand, look to see what they might be catching on. Sometimes the front derailleur gets rotated around the seat tube and sticks out into the path of the right crank arm.
Spin the rear wheel forward to make sure there is no problem with it.
Pedal backwards slowly and examine the chain, make sure no links have come apart. The side plates can stick out and catch in the derailleurs.


Tire sizing can be very confusing.  The late, great Sheldon Brown has written a web page that does a magnificent job of answering your question.


What is this brown goop on my new bike frame?

It looks like cosmoline  which is a waxy rust preventative. It can be difficult to remove from finished parts without damage to the paint. If you can, scrape some of the heavy stuff off with something like a plastic knife. Then I would try something like WD-40. If it doesn't soften it right away soak a rag and wrap it around the fork tips over night. You can see if a hair dryer will soften it without hurting the paint


Why is this STI shifter cable corkscrewing?

The corkscrew shape of the housing strongly suggests that the cable is under great tension, and putting excessive compression on the cable housing.  Since the cable doesn't completely fill the housing, it will be ever so slightly shorter around a curve than the housing that contains it.  You've put so much tension on the cable that the housing is bending under the pressure.
The most likely cause is that your derailleur is seizing up at the end of its range; normal pressure will move it over the lower part of the range, but it takes extreme pressure to move it the last bit.  I would inspect the pivots for rust or dirt, clean them and apply penetrating oil and see if you can loosen it up that way.
I see some suggestions of a broken cable strand; I wouldn't expect that to cause a problem only at the end of the action.  But if a strand is broken just where the cable exits the cable housing at the bottom of the down tube, it could be hanging up just inside the termination of the housing.  But in that case the other end of the broken strand would be visible in the exposed length of cable, which I assume you've checked.


I've built quite a few of these. They work very well. They are bulkier, heavier and marginally less efficient than the SP hub but have a good reputation for reliability.
As far as servicing goes, due to the complexity of the electronics within the hub and the necessity for components to be perfectly aligned, dynamo hubs are usually considered a closed box that you send back to the manufacturer or a specialist for service. You can of course change the bearings but it's easy to end up with a hub that no longer functions as a dynamo.
Kasai have just released a field servicable dynamo hub that is, as far as I am aware, the first of its type and the only one available. However, these things are generally reliable when not abused so I'm not certain it's the big selling point it's supposed to be.


Clip-on to temporarily convert Look pedal to stand-on style?

I don't know of any commercial attachment, but there are at least two other ways you can solve the problem.

Mikes linked to a DIY solution for eggbeaters.  You could easily do the same with Look-style clipless pedals.  Just buy a spare pair of cleats for and bolt them to a piece of wood or plastic.  You'd need to drill three holes in the flat support piece, but you can probably buy all the hardware (including cleats) for under $30.  The disadvantage of this method is that it would be difficult to properly weight the clip-ons so that they rest in a convenient orientation when you foot is off the pedal.  You may have noticed that Look pedals always sit with the front pointed upward.  This done intentionally so that you can simply slide your shoe and cleat forward into the pedal to clip in.
I know that the question asks for something to clip on to the pedal, but it seems like the real problem you're trying to solve is "How can I walk around in the same shoes I ride in?"  For that, I would propose an alternate solution: cleat covers!  These are rubber covers which fit over the cleat, available at just about any bike shop in a variety of generics and brand names.
You can, of course, also use the pedals as-is with your street shoes.  For "short" distances (every rider is going to disagree on what short means in this context) I find this works acceptably well.  I place my feet on the pedals the same as if I were wearing cycling shoes with cleats. In other words, I use the top of the pedal and place the ball of my foot over the axle.

Walking around in cycling shoes with cleat covers can be a little awkward at first because your toes are pointed slightly upward (the covers have to go over the cleat, obviously, so that adds even more thickness to the front of the shoe).  Most people get used to them pretty quickly, though, and it's really not a big deal.  One thing you can try is walking on the balls of your feet.  Normally that wouldn't work in cycling shoes because the cleat is smooth and slippery, but with cleat covers you get just as much traction as you would in regular shoes.


Since this was mentioned in a comment, freewheels are not the same as freehubs+cassettes (see http://sheldonbrown.com/free-k7.html) for details. The rest of the discussion should hold if freewheel is replaced with cassette+freehub though with minor modifications - I don't know if this bike has a freewheel or a cassette+freehub since I can't load the product page. Freewheels and chains (which needs to be measured with a ruler, due to some issues with most chain checking tools according to Sheldon Brown), (and less frequently, the chain rings) are wear items - they don't last forever (and the ratcheting mechanism can go and make a lot of noise). In 3 years, you may have exceeded it in commuting depending on weather and mileage - Last freewheel I had lasted about 3500-5000 miles (some cheap sunrace freewheel) since I ran a while with a worn chain. You don't fix a freewheel unless you have to - theres a lot of bearings and what not which makes the complexity high. Buy a replacement freewheel and have it installed, and throw the old one away (and usually, thats a good time to replace your chain as well, though you should get at least 2-3 chains / freewheel).

I wouldn't call it a banging noise (I haven't thought of what a good description of what the noise would be), but hubs which need repacking or axle damage also do make noise, so you may want to check that too. You can also get a banging-clunking noise from a failing bottom bracket as well (which can lead to a slipping sensation), so checking the bottom bracket area is another thing to do (in doing this, you'll also have to check the cranks and pedals, so this is a bit of work).


What is causing strange resistance when pedalling forward?

Sounds like your bottom bracket is having issues.  Specifically, since it's having issues in one direction that it isn't having in the other, it's probably a lack of grease or the bearing retainers crumbling.  Remove and inspect/regrease or replace your bottom bracket, depending on type and what condition it's in when you get it apart.


Rear-steer tandem with middle child saddle

While I never identified the exact bike, some similar bikes (rear-steer tandems and triplets in a variety of adult/child configurations) are made by a company called Amsterdamair.  They're based in France, only a couple of hundred km from where I saw the bike.  I suspect it was one of theirs though not quite a standard model.


Pain in the toes while cycling using clipless shoes

In addition to getting the right size shoes. Make sure the cleats are adjusted correctly. It sounds like you're getting something similar to "black toe" experienced by hikers and runners. It's usually caused by their toes getting jammed to the front of their shoes (imagine walking down a steep incline).

If your cleats are too far back people tend to point their toes down while pedaling. The cleats should be centered under the ball of your foot, depending on riding style/ experience, they can be moved forward or back by a few millimeters. in a perfect world every shop would have professional fitment analysis to take the guess work out of all this. This also happens if the saddle is too high, people don't realize this when making the switch to clipless pedals.

What I use to tell clients when buying new clipless shoes is to make sure they are snug around your arch and heel, but you're able to wiggle your toes comfortably.


What is a reasonable speed for long distances on a bike?

Speed varies widely by cyclist, depending on fitness, road conditions and traffic.  Some of my observations (cruising speed based on a flat, paved road in good condition):

20km/h (12.4 mph) - many "occasional" cyclists ride around this speed
25km/h (15.5 mph) - most commuters
30km/h (18.6 mph) - fast commuters, slower roadies
35km/h (21.7 mph) - fast roadies
any faster than that on a long flat and they're probably a racer

(based on who I pass and who passes me when riding around 30km/h)

Average speed will usually be slower than you think, once traffic stops and hills are factored in, especially over longer distances (like 80km).  On my 21km commute I'll hit 30+ on every long stretch I can, but my average still only works out to 24km/h.  For longer rides I cruise around 27-28 km/h, which is more sustainable; averaging 22-24 over a very long ride (200km) is a great pace for me.


Adjusting air pressure in the Tyre /Tire

I assume that:

you run stock Trek 3500 so you have 2 inch tyres
you are not 200lbs (judging by your photo, location and fever for fitness in your profile)

Start with 40 PSI on the rear and 35 PSI on the front and ride at that pressure for a couple of rides to understand how it feels. Then adjust +-3 PSI to see how the handling changes. If you ever get a pinch flat increase 1 PSI on front and 4 on the rear.

For trails, aim for a 10-20% height reduction on the tyre height on where it touches the ground when you are standing on the bike.


I hope it's fixed by now! But if it's not, most likely the wheel is not seated correctly. Take it out, and make sure the derailleur is pushed back so the chain loops around the cassette from the top in a counter clockwise direction.

If in doubt, I'm sure you can find a youtube demonstration showing you how...


Is my 2017 Trek Fuel EX 5 Stealth internally routed dropper seatpost compatible?

I googled the current Trek Fuel EX bikes a bit.

The EX series feature internally routed shift and brake cables the down tube, with entry points near the head tube.

The EX 9 comes with internally routed dropper post, and seems to share the frame with the EX 5, so I'd say yes.


What are the technical differences between a bike for off-road touring and a mountain bike?

Aside from touring specific braze-ons (rackss, fenders, spokes, pump, etc), the short answer is that adventure touring bikes are going to be more well suited as an all around machine where as an MTB has a narrower performance mark.

The long answer is frame geometry. Briefly looking at the geometry of some of the bikes you listed shows the Kona having shorter chainstays and a higher bottom bracket. In theory giving the bike better pedal clearance a shorter more responsive wheelbase. The Orange on the other hand has a lower BB and longer chainstays for increased stability and better heal clearance for rear panniers.

Frame geometry, however, is extremely subjective. Builders take a lot of things into account when making decisions. A lower bottom bracket for example decreases frame clearance but increases stability at higher speeds by lowering your center of gravity. One frame builder may value this decision higher than the other.


Pinnacle is Evans Cycles' house brand. Evans offers a free "6-week" check up with all new bikes. Ensure they note the spoke tension problem on the worksheet when you book the bike in.

When wheels are built, the spokes can hold a smooth curve through a crossing point, especially with thicker plain-gauge (unbutted) spokes, rather than forming a kink at the crossing point. With normal "J-bend" spokes, the bend at the elbow may keep its original 90 degree angle and prevent the head from settling properly in the hub drillings. Over time, this bend may tighten or loosen (depending whether it passes through the hub flange outwards or inwards) until the head is properly flat against the face of the hub flange. Both of these stresses may settle over time causing spoke tension to be lost. Experienced wheelbuilders will attempt to relieve most of this stress before finally ensuring the wheel remains true and has the correct tension.

Another cause of tension-loss with lighter butted spokes is wind-up, whereby as the tension is increased during the build, friction between the spoke threads and nipple threads can prevent the nipple from screwing further onto the spoke, causing the body of the spoke to twist instead. As the wheel is used, the twist-tension of wind up can release itself by unscrewing the spoke from the nipple or by spinning the nipple within the rim. Wind-up can be limited by using proper lubrication at the nipple threads and where the nipple sits in the rim, and by using brass washers between the nipple and rim (especially with a rim that doesn't have eyelets). When choosing lighter spokes, a bladed spoke (such as the Sapim CX-ray) allows the wheelbuilder to see wind-up and prevent it by holding the flat section of the spoke.


Can anyone help identify a (presumably) vintage Battaglin bike for my uncle?

I'm going to go against the grain a bit here, and say that you've got a great example of something from the dark ages of Italian bicycle manufacture. It is an early 90s bike. I know this because the phone number on the shop's sticker starts with an 01, dating it to after BT changed all the area codes.
The welding is dreadful/ugly and while the bike will be quite exciting to ride and is a great colour, they tend to be quite harsh and unforgiving, so you'll know it in your bones after you've been out for a long ride. The aluminium aero fork is completely badass though, really nice, though firm!
Last year (2020) I sold a very similar Coppi that had come from the tip; I valued it at £100 after researching past ebay listings for similar bikes. You can try the same method. The guy that has it now really likes it because it looks cool and it has a famous name on it, but it isn't a valuable bike.
Enjoy it for what it is, a cool looking bike with some Italian flair but missing the craftsmanship associated with the older bikes of the same brand.

I'm just going to add that the Coppi Gavia I'm referring to could actually be based on the exact same frameset as the details look pretty much identical.


Are all chainring compatible with all chain?

No.

The chainring needs to be compatible with the rest of the drivetrain.

Chainring pitch (width + spacing) gets tighter with increased cogs on the rear wheel. So a 9 speed chainring is not compatible with an 11 speed drivetrain.  Additionally there are new narrow-wide chainrings for single chainring setups will not work well in a system with a front derailleur.


Front fork pulling to center / "indexed steering"

This is a usual issue if the bearings in the steering tube are overtightened. Re-adjust the bearing (or take it back to the shop) and you're good to go.


"Road Bike" is a pretty broad term, but let's assume we're talking about a bike designed for long-distance road riding and not criterium or even road racing—a category used to be called "sport touring," but is now referred to as "endurance racing." Current examples include bikes like the Trek Domane, Giant Defy and Specialized Roubaix.

Also, it depends somewhat upon what you mean by "gravel racing." If you're referring to short events like Barry Roubaix that are at most a couple of hours, then a cyclocross bike would fit the bill as well as anything, especially if you already own one. The downside of using a cyclocross bike is that most are really designed for short, fast, off-road races and don't necessarily lend themselves well to all-day comfort or long, 40-mph descents.

There are a few cyclocross bikes that are designed to be less aggressive, and those are the ones that tend to turn up at gravel events. Current examples include the Trek Cronos and Boone, and the Surly Cross Check. The Niner RLT9 is marketed as a gravel bike but has a design that fits better into this category. My experience with this class of bike is that they require more effort to arrive at a good fit, and can feel more exciting than necessary on fast downhills.

"Gravel" bikes aren't all alike either, but the ones that are different than cyclocross bikes feature a longer head tube (for more upright riding position), lower bottom bracket, more fork offset and slacker angles. The best current example is the Raleigh Tamland, but the All-City Space Horse is pretty close too, despite not being marketed as a gravel bike.

To me, the best thing about "gravel" bikes coming into style is that they're actually good for a very wide variety of surfaces and emphasize comfort over raciness. Not limiting a ride to one specific type of road opens up a lot more riding opportunity.


Need easier gearing. What would the effect of changing the chainring or cassette be?

10 speed with a 42 really needs a Rad-Cage or Wolftooth Goatlink. It's a dogs breakfast, starts out smelling dodgy, and ends up smelling even worse. Some have succeeded, but many have found the conversions finicky and less than ideal. It had its day when the only 1x was XTR or equivalent, and people accepted Acera performance from 'upgraded' XT. Not sure if those third party bits fit the Deore deraileur you have though.  You could try an 42 with the Deore, but you can run into problems with lack of chain wrap and getting onto the 42 tooth cog - if it works, expect pretty crappy shifting onto the top cog.

This leaves the 28 chain ring - a good option if you don't mind loosing a bit of top end speed. Its cheap and easy to install, but only gives a little advantage over 30.

IMHO The best option by far, is upgrade to an 1x11. You need is a cassette, derailleur and shiftier and chain, so not cheap. It gives you option of a 46 cassette, and will work properly. If you cannot afford this, go for the 28 chain ring, keep the 30 tooth and save for a 1x11.


Early Klein Mountain Bike - need suggested component rebuild ideas

I think you're going to have to pore over photos and Klein fan-sites like oldklein.com to find the specs, answering one question at a time.

In terms of the BB, I believe they were press-fit bearings, in press-fit cups (like an old BMX), so you might have to remove them, measure them, and then approach an engineering supplies shop for replacements. Bearings are surprisingly universal so don't be put-off too easily by people saying "ah they are proprietary Klein bearings, forged by Klein faeries from Klein precious metals".. they are probably available!

The rear hub width can be measured easily by you, it's probably 135mm but that's a guess. Things like cranks will be square taper LX types, maybe something oddly 90's like bio-pace oval rings :)

I can't guess the model, but I don't remember the Pulse or Attitude havign internal top cable routing like that, so is it an Adroit? If so, I'm pretty sure they aren't the original forks.

Let us know how you get on! Lovely bike, I lusted after Kleins when I was 15!


Can I fit 26 x 2.2 tyres to my 26 x 2.25 wheels on my mountain bike?

If you want to put 2.2" tires in place of current 2.25" tires, then yes, you can do that.

That's less than a 2mm difference, given that tires conform to marketed width at all (which they tend not to). Generally, any smaller tire size (of compatible beat seat diameter) won't cause any issues, unless there's a huge mismatch between rim and tire width (i.e. 40mm internal width rims and 25mm wide tires aren't a good idea, same goes for 10cm fat tires and 18mm rims, but that's not your case).

I advise to consult this page on a topic of tires sizing.


Why not have the bearings in the forks themselves with through-axles?

Interesting idea but the front axle (whether is be a 15mm through-axle or a 9mm QR axle) does not rotate, the hub-body and by extension the rest of the wheel rotates about the axel via the bearings. Making such a system where the axel does rotate (e.g. unicycle fork) would require creating a capture system (which is the current function of the QR) to secure the wheel to the fork that would likely be less user-friendly that the quick-release based systems we have come to expect.


Its not a light bike, even by MTB standards, and will never be a great road bike as it will always be heavy.

Start with the easy and relatively cheap stuff - tires and tubes. Dump excess rolling weight by getting light tires an even going tubeless. The next biggest bang for your $$$ will be replacing the fork. You should be able to pick up a second hand fork for next to nothing - just watch the geometry. If you do this, canti brakes on the front is likely worth doing.

Replacing wheels is probably not worth the effort, you will shave off  a few hundred grams (admit-ably rolling weight), but it will cost big money.

Look very hard at the costs of any proposals. My guess is that for what you are proposing, a cheaper option that will give you a better outcome would be to buy a second hand bike that does what you want, rather than trying to make your current bike into something it is not.  You may have access to cheap parts, but in that case you probably have access t cheap bikes.


Building up second hand frames to resell

There could be some sticky points with what you propose in that even though you won't see what you're doing as a business, your customers probably will. You'll be accountable to doing right by them and there will be times when that will feel like work, be work, and cost you money or time like work.
The answer to your question also depends entirely on what you're paying, if anything, for the bikes and parts you're working with. In some times and places, old bikes in need of work that's hard to time-justify outside of being a labor of love are abundant. But if there's a strong used market, maybe not such much.
A very good avenue for the passion you're talking about is getting involved with community or nonprofit bike shops as a volunteer. Most cities have organizations or businesses in this vein, and most of them welcome volunteer labor to make sellable bikes out of their old parts. And, they typically have proper insurance and other trappings of actual businesses in place, which are all other ways the outside world could expect you to be a business even if you don't consider yourself one if you're just doing it on your own.
Some of these community initiatives keep a very low profile, often without any web presence, and might be tricky to find. They are sometimes side projects at various charities (focused on homelessness, substance abuse or prisoner resettlement), schools, churches or even squats. It's definitely worth asking around in local bike shops or clubs.
If you don't have a community bike shop or project nearby, consider starting one. But the time you've done all that asking around you will likely have some contacts etc.


I can't extract sealed bearings out of hub

I haven't done this one in particular, but here are some things that may be applicable:

The spacer between the two bearings may be a tubular spacer that with the axle out is simply held in place by friction. If so, with some persuasion you can nudge to one side, allowing you to hit the outer bearing with a punch from the inside out.
The inner bearing may be held in place with a circlip you presently can't see, keeping what you're trying to do now from working. It's been a while but I believe this is how Campy freehubs are put together.
An expanding collet type bearing extractor looks like it could work here. Here are the ones made by Wheels Mfg. The whole kit is expensive but individual ones are pretty reasonable. You'd do the outer bearing first and see what that uncovers once it's out.


If the effect of wind resistance was linear with respect to speed, then yes, the forces would balance out. That is to say: if pedaling into a 20 mph wind was only twice as hard as pedaling into a 10 mph wind, the forces would balance.

But this is not the case, as @Daniel mentions. The effort to overcome the 20mph wind is more than twice that needed for the 10mph wind. If we simplify your loop into an out-and-back (half directly into the wind, half with it at your back), say the wind is a constant 10 mph, and that you cycle to maintain 20mph, you can get an intuitive idea of how this works.

With those assumptions, for half your trip you would be fighting a 30mph headwind (10 wind + 20 from your own speed). The second half the "headwind" would be only 10mph (20 from your own speed - 10 from the wind). This is compared to a day with no wind, in which the whole trip would have a headwind of 20mph. The jump from 20mph to 30 requires much more energy (what is the last time you hit 30mph?) than the energy saved from dropping from 20 to 10mph.

Drag varies as the square of velocity. This means that velocity is the dominant factor in the equation (as opposed to drag coefficient).

From wikipedia:

  For high velocities (or more precisely, at high Reynolds number) drag will vary as the square of velocity. Thus, the resultant power needed to overcome this drag will vary as the cube of velocity. The standard equation for drag is one half the coefficient of drag multiplied by the fluid mass density, the cross sectional area of the specified item, and the square of the velocity.

For an excellent treatment of the forces affecting a cyclist, see Rainer Pivit's article. The graphs are especially helpful.


Approximately where is the center of mass of a mountain bike?

Assuming you want the center of gravity of the bike alone (not with a rider), there is a very simple procedure you can perform yourself, as long as you have some bike (you could borrow one):

For simplicity, strap the front wheel to the down tube of the bike, so the handlebars won't turn; You could also strap the brake levers in the "full braking" position;
Lift the front wheel from the ground, balancing the bike on the back wheel. Lift as much as necessary so the bike keeps almost falling back. Now the vertical line passing through the rear hub is the line where the center of gravity is;
Repeat the procedure with the rear wheel lifted, so that you know the the center of gravity is directly above the front hub;
The approximate center of gravity position is where both lines cross.


Usually the inside width of the rim should be at least half the tire width and can be almost as wide as the tire itself. So for a 50-622 tire anything between 25 (a bit less would probably still be okay) and 50mm should work.

The problem with wide tires in narrow rims is that the tire will be unstable in corners at low pressure and can break the rim at very high pressures. I’ve ridden 35mm cyclocross tires inflated to less than 2 bar on 13mm rims and  wouldn’t recommend it.


Can I fit a 32-630 tire on a 20-622 rim?

No.  The bead seat diameter (inner diameter) is different by 8 mm.  You cannot shrink a steel or Kevlar bead by 8mm, as they are designed not to stretch  or shrink (otherwise a clincher tire will roll off the rim in a corner).   You can try but the tube will burst out from the extra space.

The tire bead is what interfaces with the rim.


Wax lubricant - what components need wax applied to them, and what is the recommended re-application procedure?

The wax needs to be applied to the chain and specifically its rollers/pins.  Nothing else needs waxing on your bike.  (ball bearings need grease or oil, not wax)

The reapplication process is to remove chain from bike, and degrease it with a can of degreaser.  I use two rinses, first gets very dirty and the second less so.  Then the chain is hung to dry.

I use an old electric frypan to melt my wax.  I lay the chain in it back-and-forth so there are no overlaps.  Then melt the wax, using an IR gauge to read its temp.  Around 150 degrees C is good IMO, where the wax is liquid but not super-dangerous.  It should be clear too and have lost all the white.

With the chain submersed in the liquid wax, I look to see the streams of bubbles coming off the chain.  This indicates something is cooking off.  Once those bubble streams drop off, power down the pan and let it start to harden.  You want to get the chain out without the wet wax running out of the roller, but you don't want the wax to be too hard on the outside.

Let the chain cool so you can handle it.  The wax on the outside will flake off easily, making a bit of a mess so do this somewhere you can sweep.

While the chain is cooling, clean your chainrings, jockey wheels, and cassette.  Use gear floss or something to get in between cogs and make it shiny and pretty.  Also clean road grime from your frame and from within the derailleur cages.

Once its all cool, refit the chain, and test ride.  No additional lube is needed, though you might choose to oil or grease jockey wheels while the chain is off.

Some boilers have a "low spot" where contaminants collect.  Or you could peel the hardened wax from your pot and simply cut off the bottom centimetre or so, whatever thickness looks extra dirty.  Then dispose of that bit properly (area dependent)

Another option is to melt the wax so the dirt sinks, and decant the top clean layers to a temporary vessel.  Then tip the bottom layer into a scrap container, scrape the pan out, and throw the wax when it has set.

The cool thing about wax is that it melts back together so easily, and its relatively cheap, so that I could throw the whole pot full out without qualms.
5 kg of paraffin wax cost me around $35NZ, and I used less than 800g in a cooker and after two chain cleans its barely dirty at all.


Reducing saddle bounce when increasing cadence

It is a matter of both fit (frame-geom, saddle position, stem & cranks), practice, and gearing.

Everyone has a max RPM after which they start "bouncing" and you'll find this RPM is even lower if you're at a relatively low gear.

Assuming the bike fits you properly, raising your max RPM is simply a matter of practice. This can't be done at will in one session. It is a motor skill that has to be trained by drills and observed for progress. Informally you can try forcing yourself to ride at lower gears than you're used to. Over time your body kinematics will become more efficient and your form will improve (bouncing will start at higher and higher RPM's).

A cadence of 100 without bouncing is achievable by almost anyone who tries for it. Elites on a track have motionless backsides at cadences of well beyond 150rpm.


Used WD-40 on headset and now it loosens daily

Using WD40 on a headset should not cause it to loosen.  Something else is wrong.  You need to find out what that is.

First - don't ride the bicycle until the problem is identified and fixed.  Doing so might be dangerous - both to you and anyone near, as you may lose control.

If your bicycle has a new-style "threadless" headset, the stem bolts may be undertorqued.  Or, they may have been overtorqued in the past and crushed the steer tube that the stem clamps on to so that it no longer stays tight.  Those are by far the two most likely problems with a headset that won't stay tight.

Park Tool has a series of good videos on bicycle maintenance.  This one is for troubleshooting a headset:

What you do to fix the problem depends on what the problem is.

Update:

Given the posted photo, this video appears more relevant:


Nine speed derailleur on 10 speed cassette

Assuming you have Shimano components, it depends if you have an MTB or road groupset.

Shimano used the same actuation ratio (ratio of cable length pulled to lateral movement of derailleur cage) for road 8, 9 and 10 speed systems then changed for 11 speed. Theoretically a 9 speed derailleur will work with a 10 speed shifter and cassette.

On the MTB side the change to a different actuation ratio was made at 10 speed, so a 9 speed MTB derailleur will not work with a 10 speed shifter and cassette.

A well known exception is road Tiagra 10 speed 4700 series which uses a road 11 speed actuation ratio (although I'm not sure that it's exactly the same, a Tiagra 4700 10 speed derailleur may not work with a 105 5800 or Ultegra 6800 group.)

Indexing is not too hard to get right (if you have matching shifters and derailleurs of course). Park Tool has a good page that explains how it works.

If you cannot get the indexing right at both ends of the cassette you may have another problem. A bent derailleur hanger is a common culprit. Cables hanging up in the housings is another.

If the chain is skipping over sprocket teeth rather than ghost shifting you likely have worn sprockets.


Answer:  reset your expectations and give it a go.
The first race I entered, my only goal was to finish.  Second time I did it, the goal was to pace better and finish with a better time than my first effort.
After that, personal improvement is really the goal, developing racecraft and strategy.
When riding in a group/bunch/peloton/paceline of cyclists, you won't believe the amount of boost received from the draught.  Simply watch and learn, parrot what others do, and listen to any advise offered.
It would be good if you could do some group riding before a proper race.  Look for a publicised group ride and try to join.  It can be hard to ride close enough behind someone to benefit from the aero gains, and it can be unnerving to be followed closely by someone.  Practice will help.
Even if you fall off the back of a group in short order, you'll experience what group riding is like.  It can be addictive!

If you possibly can, ride the race route beforehand.  Even some of it is better than going into it cold.  Use an app like Strava etc to log a time, and expect that a bunch ride will drop your time by about 20% assuming similar weather.
Gender is relatively irrelevant in a race - different categories are all run at the same time, perhaps with a few minutes gap between the start times.  IE the full length race might start at 0800 with the half-length version leaving at 0810.   So there's always some mixing between classifications whether they're age, distance, gender, or whatever the race organisers chose.
As a large middle age man, I'm able to descent faster than a lighter rider, but I have to work to maintain and carry that momentum up the next climb.   And then those lightweight little weeds pass me at triple my climbing speed.  Knowing what kind of road is coming up, whether its a long straight descent or a 20 minute climb helps you anticipate and pre-react.
Upshot  life's too short .  Get out and give it a go.  I've seen a guy in his 70's win his age group on a 1960s three-speed city bike.
You can't finish unless you start.


Why are bicycles triangulated at the back but not at the front?

Forks on bikes and motorcycles do pay either a weight or stiffness/strength penalty for their lack of triangulation. One can imagine systems for steering the front hub with a linkage rather than a conventional cantilevered fork. That sounds more heavy and complex than it's worth for a bicycle once you have it able to handle the full range of motion needed, but that's just a guess, and it's not say there's not some other application for such an idea.

One piece of the answer is that the main drawback to a cantilevered fork is that they're vulnerable to being smashed into things head-on. If all else was equal that would be a nice vulnerability to eliminate, but it's hard to imagine a situation where all else is equal, especially considering the forces the bike encounters in such incidents are quite high. Good forks offer a degree of valuable micro suspension even if they're not suspension forks, and losing that just to be able to smash into things would not be a welcome compromise for most.

This is to say that a more triangulated design employed in a way that increases stiffness likely would be unwanted. If you could keep it at the same stiffness but with less weight, I would say the main reason that doesn't exist is no one's been able to figure out how.


You could try leaving the bike in your car, but covered with a dark blanket so that its not visible at night, it would be even better concealed if you took the wheels with you into your room at night as it could make the blankets profile flatter (handlebars turned to be inline with the frame).

If you dont mind taking it apart even more (pedals and wheels) you could even get a bike box to put it in, when you cover it with a dark covering then it would present a flat surface in your car which would be almost invisible in the dark.

Additionally, park near a street light or as close to the entrance as possible so its covered by the "security cameras" you mentioned.


Is there a measurement for tyre profile or height from rim?

If you look at the ETRTO specification of a tire you are thinking of using, e.g. 47-406 (a 20 x 1.9" tire) the total diameter of the mounted tire will be pretty close to the rim diameter plus twice the tire width: 406+2*47 = 500mm ~ 19.7".  (the designation 20" wheel here comes from the diameter of the common 50-406 tire).  The width of the tire will vary depending on the tread, but will be within a few millimeters of the ETRTO width.

While the most common 20" (406) tires are ~2" / 50mm wide (especially on kids bikes), it is possible to find skinny 20" tires but you need to get skinny rims to go with them.  ( Schwalbe has a chart of rim widths http://www.schwalbetires.com/tech_info/tire_dimensions).

As others have mentioned, if you have rim brakes, only one or the other of 406 or 451 will actually work for you and if it isn't a BMX frame, I would guess it is more likely to be the more common size of 406.


What tire should I put on my road/commuter bike to prepare for a New York winter?

You say you've got a small apartment that can't accommodate two bikes, but how about two sets of wheels?  The only thing that can deal with ice is studded tires, so for those 20% of the days that include ice, you need studded tires.  Your Tricross should be able to accommodate such wheels, so it would simply be a matter of changing wheels rather than buying a whole new bike or using transit.

As for those days it seems okay in the morning but turns into an icy day in the evening, all I can suggest is paying careful attention to the weather guessers and guessing conservatively.


First up - consider buying a bike in the colour you want.  That will be the easiest/cheapest solution.

Anything with threads (internal or external) and anywhere that has flat machined surfaces for nuts/bolts to tighten against should be masked to prevent paint.  If you do paint surfaces like dropouts, the paint will crack and flake off quickly.
You should also mask off anything you want to stay chromed, and remove all parts like groupset, bottom bracket, seatpost, bars, stem, cables, etc.
The best paint job comes from a completely blank frame, so remove all decals/stickers and wash the bike to remove any oils.  Then scuff the existing paint with sandpaper all over to give the new paint somewhere to tooth into.
I would also strongly recommend you take lots of before photos and post them here, along with the serial number.  In the future someone might come along asking to identify their dirty old BMX that was overpainted decades ago.
Progress and post-painting photos might be cool too.
Do consider that this painting will void any and all warranty as well.


Why do my handlebars wobble left and right?

Different bikes can have different geometry. The head tube (the tube that continues the line of the front forks up to the handlebars) angle has a big effect on how the bike handles.

A steeper head tube makes the bike more "twitchy". You can feel like you're all over the place. A bike like this would be a more serious road bike, and if you are used to using flat handlebars then it probably has narrower handle bars (drop bars) also.

Both of those make it harder to control, until you get used to it.
So my advice is: keep trying, it will get easier.

For more reading see

Frame geometry
Explaining the effects of frame geometries
Geometry of bike handling
What effect does head tube angle have on a bicycle?


Looks to me like you've managed to unthread the brake boss from the frame.  That's not part of the brake lever.

Normally you'd undo the dome-head silver bolt visible on the left side of your photos.

If you stick a 5mm allen key/hex tool in that bolt, and mount the allen key in a vise would be a start.  Then you need to grasp the thread and undo it without damaging the thread.... that's difficult.

One "dirty hack" is to find two nuts of the same thread and internal diameter.  Thread them on fully and cinch them up against each other as hard as you possibly can.  Then put those two nuts in your bench vise tightly, and use a long arm 5mm hex tool to lever it off.


Would a Portland Design Works 700 x 37 fender fit a 700 x 32c tyre?

It's never going to work great, but whether it works at all depends on how much vertical clearance you have to work with. When you push the tire size, what happens is the fender can't wrap around the tire properly, and instead the tire wants to rub against the "gutter" or side of the fender. If you can simply gap the fender further away, you might be able to get by, but many bikes won't give you the ability to do so sufficiently.

Having this little overhang tends to result in an installation that needs readjustment all the time and wants to rub.

Also the actual inflated width of the tire is important here, especially since rim width can have a major impact.


How to define if brake pads suitble for carbon clinchers

Yes, you need special pads. Every manufacturer of carbon rims has their own recommendations for what pad to use, which you should follow. Zipp makes their own pads.

Normal brake pads are harder, and can wear away the carbon rim surface. This is very bad, of course. Brake pads for carbon rims are softer and wear down more quickly so that they preserve the rim.


It depends on what type of tubeless standard you are using.

UST

UST rims are designed to be able to be inflated with a floor pump. The rim profile has an inner channel. The tyre bead should be placed in this as per the picture when you begin inflating the tyre. When it reaches a high enough pressure it pops into place and you can continue to seat it easily with the pump. You can also add sealant before inflating with USTs.

Tubeless Ready

Tubeless Ready have a shallower rim bed that require far less volume to inflate with a floor or CO2 cartridge. This is trickier with a floor pump and people often remove the valve core to allow a higher volume of air in. Once the tyre is suited you can also to remove the core to add sealant.

Ghetto Setups

If you are using any other tyre/ rim combination it's really just luck if you're going to get a tyre to seat with floor pump, compressed air or ever at all.


The dent is not in a high stress area.

If the headset turns OK, I would ride it.

Inspect regularly for cracks, both near the crack as well as the welded side of the headset.


No, not officially.
The authorative document is https://bike.shimano.com/en-EU/product/component/grx-11-speed/RD-RX810.html which says

MODEL NO
RD-RX810

SERIES
GRX 11-speed

Low sprocket_Max.
34T

Low sprocket_Min.
30T

Max. front difference
17T

Top sprocket_Min and Max.
11T

Total capacity
40T

So the minimum and maximum tooth count on your cassette is 11.  That says it has to be 11 tooth.
At the big end, minimum is 30 and maximum is 34 tooth.  Since your desired 40 tooth is more, its out of spec.
Can you make it work?   40 is a long way from 34, and while you could probably push it to 36 without issue, 38 is getting iffy and 40 is unlikely.  It may be possible with a derailleur extender like a tanpan or wolfs tooth, but then you're compromising somewhere else.  Read on...

Separately there's the part of the question about is this going to work with a single chainring.
I'd guess that you're not exceeding capacity, so its nominally no worse than simply riding on one chainring of a double.  You're only using 34-11=23 teeth of capacity.  However the rated "40T capacity" is not all in the rear cassette, its up to 23 teeth in the cassette and up to 17 teeth in the chainring difference.

Upshot 42:34 is not a terrible gear for climbing, but its nowhere near the sub-1:1 range like a triple could give, and not approaching what a compact double could do.  All depends what you want to ride up and how fast.
Answer You want a RD-RX812 which has a 40 or 42 tooth low gear rating.  That would let you use 42:40 as per your question.  You need an 11 speed chain as well, and an 11 speed GRX shifter that suits your bars and brakes.  Downside, 42:11 isn't going to spin you fast on a downhill or a tailwind, but they're not as common with offroad riding so less of an issue.
I'd consider going 42:42 cos the meaning of life at both ends of your transmission is fantastically nerdy.


Native BB30 crankset or adapted Shimano?

If the frame is made for BB30 I'd recommend using that.

Advantages of using native BB:

BB30 spindle is thicker (30mm) and stronger than a gxp (24mm)
No extraneous parts

Advantages of using adapter:

Ease of service - no bearing press needed except for initial install, after which you will have a threaded BB that's easy to remove.  BB30 requires relatively expensive tools to service, e.g. Park Tool bearing press and puller, which most enthusiasts don't own.  Also, the fact that you only need to service a BB30 once in a while (maybe once or twice a season) makes buying the tools less attractive when one can just take it to the LBS and have them pull your BB30 for relatively cheap.
Q-factor - can be an advantage or disadvantage. Your stance will likely be wider with the adapter. I consider this less desirable but it's all about the fit. I like a narrow stance.  You may have knee pain if your q-factor is too narrow or too wide


Shimano MTB and Road Components Compatibility

You need a 10 speed chain. You can buy one from Shimano, SRAM or KMC. There isn't a compatibility issue between different Shimano/SRAM Mountain/road drivetrains in regards to the chain. The only 10 speed chain on the market you can't get are ones marked for Campagnolo (*).

I'd prefer an SRAM one (e.g. PC-1051) or KMC one (any 10 speed chain that is marked Shimano/SRAM compatible, which is pretty much all they sell) because they use a special link, rather than a special rivet like Shimano (which is annoying, at best). The SRAM link is one time use, but the KMC one can be disconnected multiple times.

(*) Well, depending on who you ask, it will work; I don't know anyone who would actually run that situation. Plus, there are 2 varieties of 10 speed chains for Campy as well.


Why is there so much friction on my rear wheel?

Possible options could be

Damaged bearings
Bearing closed too tight
Bent axle
Spoke that touches the axle (I had it once when I put a straightened j spoke instead a straight pull one).


Why wear sunglasses in indoor velodromes?

Track cyclists are travelling in excess of 30mph.  At that speed you need eyewear to protect from the 'wind'.


Steel (531) road bike conversion to disc practicability

Answer: Its not worth doing, from a financial stand point.

Adding disk brakes to a frame is expensive, risky, and ruins any vintage value the frame had.   The stays are not engineered or designed for the new sideways loading.

Also, you talk about stays, but braking on the rear wheel is nowhere near as good as braking on the front.

If you're dead-keen on fitting disks to this frame, then a better solution is to buy a new front fork with disk mounts, a new front wheel or hub with disk mounts, a front caliper and rotor, new cable/hose, and a new brake lever that suits.   Keep the old fork and parts too, that way you can revert to original spec for no cost.

If you want a disk brake bike for bad weather, buy a second-hand MTB and fit mudguards, leaving your loverly vintage bike for rides.


Extending range on SRAM PG-1130 cassette / cassette specification

SRAM PG-1130 cassettes fit on a Shimano HG freehub body, not the SRAM proprietary XD driver body.

If you see 11-42t cassette fits 10 and 11-speed non-XD™ driver bodies in the description on the SRAM page that means HG.


You seem to be looking for a puncture resistant semi slick mountain bike tyre. That's a whole set of compromises, and they're not intercompatible.

For a mountain bike tyre you want big knobbly sections and a thin tyre casing so it flexes easily when you run it at low pressure. But on the road you want high pressure, and for puncture resistance you need a thick casing. The problem with getting both big knobs and a slick tyre is obvious, but that's the most easily solved part - a semi slick tyre - and there are lots of them available.

Problem is, off road they don't have as much traction as a proper MTB tyre, and on road they're fine until you lean the bike, at which point they lose traction. I've used these for a while when my commute had an off-road option, but I quickly decided I would ride that to work only when it was dry enough to do it on slick tyres. The semi-slicks worked better than slicks on the gravel, not detectably better in mud (but they did throw more mud up onto me and the bike), and on the road the "lose traction on corners" feature was downright dangerous.

My solution was to buy a second hand mountain bike and use the wheels off that for offroad riding (the bike itself was in very poor condition, so it wasn't worth fixing, but the wheels were ok).


The small chain ring is considered the first gear, so it goes 1-2-3. The derailleur spring pulls the derailleur always towards the smallest chain ring, which makes sense if the cable snaps during a ride: you could still get home without having to walk your bike on hilly terrain. If it was always on the big chain ring, you would need some serious legs depending on your local hills.

Did you ever check a Shimano manual regarding the front derailleur adjustment? They explain very well what you have to do in detailed steps. But if you can't get it right using the mentioned Park Tool tutorial, i would really recommend visiting the LBS.

What i am missing in the Park Tool tutorial is the step where you have to loosen the inner wire. This should be "Step 0". The wire has to be loosened while adjusting height or rotation of the derailleur.


Skipping bolts on seatpost , please help?

₹ 555 (Indian Rupees) is about $11 NZD or about $7.50 US, 5.64 UKP or 6.27 Euros.
So you've got a seatpost that is incredibly cheap and likely made of low-grade metals.  Zooming in a bit shows the terrible surface finish, and the inside won't be any better.

By repeatedly alternating between tight and loose, the threads inside have become "stripped" and there's not enough metal left to hold the bolt.    I bet you found little half-moons of metal flaking out of the hole when removing the bolt fully.
There's a chance you over-torqued the bolt too, which uses the bolt's thread as a kind of lever to force the metal threads off the sides of the hole.
You may be able to put a wider bolt in after re-cutting a new thread with a tap, but given the cheese-nature of the metal, it won't last very long.  You can also fit a replacement thread, but the tools for that cost more than a decent seatpost.
On the other hand, if its the bolt which is missing its threads, and the threads inside the clamp are still okay, a replacement bolt would resolve the problem for now.  Do make sure its a quality bolt.
Buying a better-quality seatpost will fix your problem.  For me, a low-price good one is four to five times as much.   You don't need to spend excessively, but based on the pricing and what has happened, it was a piece of junk.   You might also explore returning the item, though that is up to you.

Your second photo clearly shows no threads left in the square "nut"  If you could replace that with a thicker nut it would hold for longer, but some other part could fail too.  I would expect the pressed metal rail holder to give up next, or maybe the bolt itself.


My chain did something similar but less severe, I was cleaning it and adding dry lube from a posh brand, then keeping it and riding it indoors. The chain got gummed up and harder to turn.

What I needed to do was to clean it more thoroughly. I might have been breaking down some of the oil every wash but it must have been leaving a cumulative sticky residue, 1, adding friction and 2, preventing new lube reaching every inner surface. What I was doing was effective for a different lube but not the one I had switched to.

Try giving a more thorough wash (degreaser first) and use a sponge on the chain rollers to carefully work the dirt out of the links. Then rinse thoroughly. Dry the chain with a towel and allow it to dry fully before adding new lube to every link and turning the chain backwards to work it in. Wipe away excess lube.

I you think any dirt or residue remains when you’ve rinsed the chain, repeat the cleaning.

I don’t think ‘bad’ lube would be the main cause, because you should be able to clean away any bike lube with the right cleaner.


The Park Tool CWP-7 is the tool for this job. Remove the outer cap using an allen key and then install the CWP-7. There is no need to tighten it ultra hard. Then use an allen key on the CWP-7 and start tightening the bolt. The extractor will "penetrate" the crank and the crank arm will start detaching itself from the other crank arm which also has the spindle.


How are the racing categories in the US decided?

Usually, it is the USA Cycling racing categories that people are referring to.

Road Upgrades
Guidelines and Notes by Category:

5-4:   Experience in 10 mass start races.
         Local Associations may also establish policies where upgrade
         credit is given for taking asanctioned rider education clinic.

4-3:   20 points; or experience in 25 races with
        a minimum of 10 top ten finishes with
        fields of 30 riders or more, or 20
        pack finishes with fields over 50. 30
        points in 12 months is an automatic upgrade
        - USA Cycling-sanctioned rider camps and clinics that are
          approved by the Local Associations for upgrading will
          count as a maximum of three upgrade points when upgrading
          from category 4 to 3

3-2:   30 points
         40 points in 12 months is an automatic upgrade

2-1:   35 points
         50 points in 12 months is an automatic upgrade


Deformed/uneven/bumpy wheel/tire/tube, how to diagnose or repair?

It's hard to tell from that video - a side view would have been more useful.

From what you say it seems the rim is actually round in both planes - it doesn't wobble side to side or up and down as it rotates, so it's not that (but I can't see the rim in the video so I don't know for sure).

If the problem is the tyre it will be either because the tyre is not seated properly, or it's defective/worn out. But that sort of dip is unusual for a worn out tyre - normally they bulge (then pop). If the tyre isn't seated properly you'll normally be able to see it when you look at the side of the tyre. Where the dip is the normal markings on the side of the tyre will dip in too, meaning the bead has been pulled in on the rim rather than being pushed out against the sidewall/braking surface. If you're lucky that will have happened because the tyre wasn't installed properly. This is probably only on one side of the wheel, so check both sides. If it's on both sides probably the tyre is the wrong size for the rim, or you may just be particularly unlucky and have a slightly oversize rim and a slightly undersize tyre.

To fix, mostly deflate the tube, then work round pushing the bead in on the rim as though you were about to remove the tyre. Then pump the tyre back up slowly until the bead pops back against the rim. When this happens stop pumping, and make sure the bead has popped back all the way round. if not, work the tyre with your fingers where it hasn't popped - just squeeze the tyre in with your fingers. The movement should be enough to seat the bead properly.

But if it's a size problem you will need to buy a new tyre. If the size should be right but isn't, try a different brand of tyre. Some manufacturers are known to make "tight" tyres (slightly undersize beads), others do the opposite. Be aware that it is sometimes possible to put a 700c tyre on a 27" wheel (700c = ISO 622, 27" = 630 or so. ISO is roughly diameter, so the difference in circumference is 25mm or about an inch). It's very, very difficult to do, and shouldn't be done at all. If you're unlucky, you have one of the weird size wheels that's almost a modern size. Sheldon Brown discusses wheel sizes here

If the problem is the tube it'll be slightly harder to detect. Tubes are not every strong compared to the tyre, but if you somehow tie a knot in the tube that will affect the shape of the tyre. The most common problems here are a twist, which basically turns the tube into one of those balloon animals; and getting folded back on itself. The fold usually happens when the bike is ridden with the tyre very under-inflated or flat. The whole tyre rotates slighting on the rim as you brake or pedal, but the value stops the tube rotating with it. Until it breaks off, anyway. So you get a stretched part of the tube, and the other side of the value all the slack collects and folds up. When you re-inflate the tyre there's wobble like in your video.

I describe that first because it's easy to check and fix. Deflate the tyre, pop it off, and if there's a big lump of folded up tube next to the valve, there's your problem. Often you can tell just by deflating the tyre than pressing down around the valve.


Can I use a SRAM 10-speed cassette on my Shimano 105 9 speed groupset?

If you had 9 speed on both the wheel and trainer, or both 10 speed, then it would likely work fine.
However you have once of each, and that won't work well together.  There may be one or two cogs on the 10 speed cassette that line up with a 9 speed position on the rear derailleur.
Your best option is to buy another 9 speed cassette and keep the whole lot 9 speed.


What speed of wind gust will cause a cyclist to swerve by 1m or more?

Having ridden near Bristol this morning in a similar forecast gust speed, I'd say you're right to be worried, but keeping aware of the wind direction and speed can make a huge difference.  For example: passing side roads on your left, if the wind is coming from the left, you may want to aim slightly towards them so that you get blown back towards the middle of your lane (swap left/right for US readers).

Considering my ride this morning: I was lining up for a left turn at a T, then was suddenly closer to a right turn position as the gust coincided with me leaving the wind shadow of a house.  That was probably a sudden smack of 45mph wind broadside on, I'm tall and ride a hybrid with a rear pannier, and tend to sit up tall approaching that junction to see better (also loose clothing, so close to worst case).  It probably moved me 1-1.5m sideways.  I was already braking and unclipped.

If you're already riding in the middle of the lane you're in a good position.  But don't forget that when that wind is in your face you'll be doing something like walking pace, so you have to balance your right to the road with the behaviour of drivers, and that balance is shifted both because of your reduced speed and the worse-than-normal effects of close passes.  Taking the lane, but not slightly left of centre would make a big difference here.

Also:

Use your ears - you can normally hear a gust coming before it hits you.
Remember that when around queued vehicles the wind may change unexpectedly and you may lose most of your headway.
Don't forget that you will be going more slowly than normal, giving you more time to react (some of that wind will be in your face).
Don't fight to hold a perfect line - if drivers can see you being blown about they'll give you more room (I'm not saying exagerrate it either).


Front wheel "shudder" or "pulse" when braking

By your description, it totally seems to be some slight irregularity on rim surface, be it a bent spot, some fluctuation around valve-hole or seam, or some slight variation on total width.

I had the exact problem you described three times: after hitting a pothole too hard once, and after my bike fell off a moving car's bike rack thereafter.

Both times, it was some rim irregularity, and it was on the same rim. First time, I kept riding and the very rim wearing out with braking eventually solved the problem. Second time, I had to put a new rim, because the "pulse" was very intense and dangerous (fork flexing and all).

The third time I had this problem, I had a defective rim which eventually cracked on the side, and I felt a progressive worsening of this "pulse".

AND HERE GOES THE SOLUTION!

I noticed this irregularity caused an assymmetric MONLIGHT REFLECTION because I was riding at night, leaned the bike to the side, and was marevelled by the beautiful circle of moonlight on the shiny breaking surface of the rim. But there was a bent spot, pretty much invisible to direct observation.

So, I propose you go with your bike close to a shadowed wall on a very sunny day, and use the braking surface of the rim to reflect sunlight on this shadowed wall, optionally letting the wheel turn slowly, and repeating the procedure with the other side of the rim.

For sure, if there is a bent spot, the slightest one, you will see it.

You can increase the distance to the wall to make the effect more obvious, and you should expect some natural assymmetry. The "abnormal" thing to watch would be a very localized spot of aberrant light distrtibution.

EDIT: suppose you found the micro-bent spot, a good way to wear it away is to put not-so-expensive brake pads, go to your favourite muddy downhill track in a wet day (preferrably one where the weels completely sink in the mud), and use the brakes mercyless. Your rim will begin to shine!! (pun intended ;o)

Hope it helps!

(well, you could always turn the bike upside down, spin the wheel, close your eyes, and literally feel variations on rim surface with your bare fingers. It is not so sensitive as the sunlight method. Do it with caution!)


How do I increase my cycling duration or distance limits?

As to your initial question, there are no hard, general limits.

Listen to your body and don't push yourself if anything starts hurting. If something (like your Achilles tendon) hurts only afterwards, that's also a clear sign you overdid it and you should note what you did so you can go a little easier next time. Of course also wait with your next tour until nothing hurts anymore.

The issue when your whole body is really exhausted as Daniel says should only arise when you overdo it a lot and/or don't eat/drink enough. In my own experience, you will notice that you feel stupid and very simple things like going through a roundabout and taking the right exit will suddenly seem as difficult as a math problem and eventually (not in my own experience, luckily) you will faint.  As long as you are looking out for the signs of this, really I don't think anything bad should happen. Just don't push yourself too much. If you reach this exhausted state, you might feel pretty bad (in a general way, tired, mostly) for several days.

Some proper high-calorie sports drink should help to keep your body running if you don't eat enough, but there is a limit (raised by training) on how much your body can metabolize so sooner or later you'll still run into the above issue.

The question was edited to make the question more about how to raise said limits. I don't actually have a lot to say about this. It will go up by itself the more you train, it's as simple as that. Regularly go to your limits, but not beyond them (or not too far). You will improve.

Personally my way to do this is to just use your bike for all the travelling where it's at all possible. Commute all year round. Visit a friend or parent 50km away? Maybe you can go by bike (and use their shower). Need groceries? Go by bike.


Yes. The shorter spokes go on the drive side. Satisfy yourself by looking at the picture below:

Imagine two right-angled triangles sharing a common side (the red-dashed line). The hypotenuse of the left triangle (non-drive side) is longer than the hypotenuse of the right triangle (drive side). Generally only by a couple of mm, but it makes a difference.

Failure to observe this will mean in the first place that you might not be able to attach all the spokes to the rim. Even if you manage this, you'll likely not get the wheel in dish. Assuming that you asked the question because you've actually done this, my advice is to undo it and to start building the wheel again. On the plus side it is likely you won't make this mistake again ;-)


It depends on how much the rim is bent, and if the deformation is lateral (side-to-side) or radial (in the direction of the spokes).

Take the wheel to a bike repair shop and get it evaluated. The shop may be able to true it. If it's not repairable they should be able to recommend a replacement.

As a safety precaution, don't ride the bike in the meantime.


Shimano Dura Ace wheels do not require the extra spacer behind the cassette that every other wheel requires. So, no the 7900 wheel should not require a spacer with the 7800 cassette.


Dahon is an American bicycle company founded in 1982 by David T. Hon (Da Hon). They are famous for their folding bikes, which are manufactured overseas.

Dahon officially markets under its own brand name as well as through affiliated brand names such as Yeah, Biceco, and Novara.

But in the years after the Dahon came out, people noticed that very similar-to-identical folding bikes were being sold under other (often unknown or house) labels. These were often not the newest models, but a generation older and with some changes such as different grips, locking mechanisms, or gearing.

It's unclear whether Dahon officially licenses their older designs to other companies to market under their own names; whether these are "excess" but official frames that have been repurposed or made during a "ghost shift"; total rip-off designs using the original plans; or, simply "inspired" by the Dahon design. Given the variety from perfect-clones to off-copies, most probably all of the above.

Because of the family connection and resemblance to Dahons, these folding bicycles that appear to use the original Dahon designs are called Dahonesque.

Note 1: some people also use the term Dahon-clone to refer to exact copies.

Note 2: The Tern Company was founded by the wife and son of David Hon (the Dahon founder). The first Terns were definitely Dahonesque, but recent models show considerable genetic drift, perhaps enough to make them their own species.

Finally, let's play, Spot the Real Dahon!

From top to bottom: Dublin Explorer (a £99 copy); the real Dahon Curve; the Fnhon VG2018 - an unlicensed clone; the real Dahon D9.