Some example from Austria and Germany for new bikes:

~300€ will get you a cheap city/trekking bicycle with the cheapest components and 3x7speed gears. Often not assembled properly, low quality and heavy.
~600€ will get you a solid brand-name city/trekking bike or cheap MTB.
~900€ is where real road bikes and MTBs start.
>1300€ here you get good aluminium frames and Shimano’s or SRAM’s mid-range components.
>2000€ carbon frames, upper mid-range components. From this point on you mostly get improvements in weight.
>4000€. The best of the best. Road bikes with electronic shifting, aero wheels, <6.8kg weight etc.

I think for the US you can just replace € with $. Of course prices depends on region, discounts etc.
I don’t think bicycles in general are particularly expensive, you probably just looked in the wrong place.
As Pere points out in the comments, used bikes are often a good idea, especially when you need a cheap (<300€) bike. But in my opinion you should have some knowledge about bike fit and bike mechanics to be able to properly evaluate (and repair/maintain) a used bike. Sometimes good bikes are sold as “broken” for a few dozen Euros despite only needing some adjustments, a new chain and new tires.


Why is my drivetrain so noisy after replacing the chain?

Fixed gears don't have as much tolerance for mismatched wear patterns as geared bikes, because there is no "give" in the drive train system.

The small amount of wear shown on the used cog is enough to cause this kind of noise in the case of a fixie. I'd be surprised if the same amount of wear caused you any problems at all on a geared machine.

It's also possible that the chain was over tensioned. I know you said that you use a tensioner, and that you didn't change the settings, but you used a new, unstretched, and therefore shorter chain. You may have needed to relax the tension by a small amount.

As you removed the wheel to change the cog, It may be that the tension has changed as well. Hard to say for certain, as you made the noise go away.


Presumably you are looking for a cheap bike to ride in harsh winter conditions. The advertised price of 35,960₽ is about US $615 (at the time the question was asked) which would be considered a quite inexpensive bike here.

Your choice or tires is going to make a much bigger difference than a carbon fiber vs aluminum fork. An aluminium fork will be fine, but look for a bike with clearance for bigger tires.


7x9 is the size that tends to be used when they're trying to make it compatible with "any" seatpost. Normal metal rails are 7mm, so making it a 9mm oval/rounded rectangle fits in in most cases. It's kind of a hack solution that's become normalized. If you look you could find seatposts where a 7x9 will give either iffy thread engagement or interference/awkwardness with the clamp, although neither are common issues by any means. And of course posts exist that clamp the sides of the rails, and you need to avoid those. What you do want to look for is a post that's got nice abundant contact area with the rails and isn't going to press on them with any sharp edges. You can find posts that are counterexamples of this, mostly older basic ones, and thats what you want to avoid.


Which is the most stringent bicycle helmet certification?

To test a bicycle helmet you attach it to dummy head and drop it from a height onto a solid object. The acceleration experienced by the head is measured, if the acceleration is too high the helmet fails. Stringency of the impact test depends on how high you drop the helmet from and the maximum acceleration you allow for a pass.

There's a comparison of the various standards here. Snell B95 uses the largest drop (2.2m) and is the most stringent on that count, although it allows acceleration of 300g. Other tests (e.g. Canada, Europe) have a lower limit on acceleration, but the drop heights for these standards are also lower.

If you can find a helmet that is Snell certified and also Canadian or European certified then go with that. If not, then just Snell certified is probably the best bet.


Jeans and similar trousers wear fast on saddles. This is partly the seam on the inside of the leg, which is more of an issue on thick, high-friction fabric. They're also not very comfortable for riding in, especially if they get wet (including from sweat). Sitting in wet clothes when you arrive isn't much fun either, and smart stuff doesn't like being rained on.

My solution on commutes over about 8 km (5 miles) is to get changed. This also means I don't get chain oil on anything that matters. I'm not suggesting lycra as a default for commuting; apart from anything else pockets are useful at the ends. Gym shorts are good in summer, but in winter I suggest quick drying hiking trousers, and cheap ones at that. The pair I relegated to bike commuting have done a few thousand miles/km without noticeable wear.


Riding experience of 21-speed vs. a 7-speed?

Do you use the front derailleur?  It seems many people in reasonably flat areas do not.  If not, you are riding a 7 speed.  Take a ride and notice what gears you are using, particularly on the steepest climb and the steepest descent.  The lowest gear will be with the smallest chainring in the front and the largest cog in the back.  The highest gear will be with the largest chainring in the front and the smallest cog in the rear.  Your gear ratios come from dividing the number of teeth on the chainring by the number on the cog.  Now you can compare the ratios available on the new bike to what you are using on the old one.  If you are having trouble up hill, do not accept a bike with any higher a low gear.  If you want to pedal down hill, do not accept a bike with any lower a high gear than you use now.

If you are using all the gears you have, a new seven speed will either have a much narrower range of gears or much wider spacing between the gears.  The spacing won't be a factor 3 wider because the gears overlap.  If the new one has the same range, try shifting two gears at a time on the old bike.  Is that too large an increment?  If so, you need more than seven gears.


This question explains that if you travel on uneven ground, your average speed drops. This is because you spend more time in the slow climbs and less time in the fast descents.


Can I use a derailleur hanger in my old frame?

There are replacement hangers to adapt a modern deraileur to horizontal drops. I have never used one and can't say how well they work. BikeParts.com lists this Shimano compatable piece ID#: BPC109497 that  may do the trick. Talk to someone at the LBS (local bike shop) first,if you get it locally you will be able to try it for fit before buy it.


Brifters plus quill stem suggests around 1997 or 1998 vintage.

The rear brake bridge formed like a front fork, instead of two full seat stays up to the seat post... that's quite unusual.   Makes the smallish frame look even smaller.

I'd guess its a 7, maybe 8 speed on the rear, can't see in the photos.

The front fork has relatively little rake (curve) on the legs compared to older bikes, which also suggests late 90s.

That's a gorgeous bike - you should look after it and will enjoy riding it.


Do you need brakes on a trainer / on rollers?

No. For fixed trainer, it should be obvious.

For rollers, rolling resistance is higher on rollers than on flat surface. Wheels don't also have much momentum, so you can slow down by freewheeling for a few seconds. The only use for brakes is preparing to dropping off the rollers: rotating tires leave a nasty skid mark on the floor but brakes stop the wheel immediately.


How can I remove the stripped plastic cups of a bottom bracket?

FAG bottom brackets (BB) with plastic mounting rings are very common in Germany. The cartridge bottom bracket is really good and resilient, however the polyamide (PA) mounting rings are horrible.

As you found out there is a tool to turn the splined outside (rosette shaped). It is inexpensive and easy to get in Germany (< 10EUR). However, unscrewing the PA mounting rings often fails. The polymer material conforms to the thread and all its imperfections and thus has too much friction in the thread. The bulk of the material is not strong enough to transfer the momenta needed to overcome this. As a consequence it is very easy to simply twist off the entire outer part of the cover including the splines or mangle the splines.

I had to remove such brackets before. In one case I could remove the mounting ring on one side of the bracket with the tool. It is easy then to take out the cartridge and get out the other shell. If one side fails, be very careful with the other one. Try to use penetrating oil, use plenty of it and give it a lot of time to enter. Make sure you turn the correct way.

both mounting rings stuck

failures

Recently I had a bike where both mounting rings were stuck*. In my case the mounting rings were pressed in. My frame had no threads whatsoever in the bottom bracket shell. I will briefly describe what I did and then continue with how I think it could be done better. Starting with my entirely futile first attempts.

I supported the frame well on wooden blocks and used a mallet to hit the spindle. This had no effect whatsoever.
I used a clever arrangements of a vise and wooden blocks to push the spindle.
I removed the outer part of the mounting ring, which serves as dust cover, with a woodworking chisel. I removed more PA material to form a 45 degree face until the outer edge of the cartridge shell was accessible. I selected a deep socket with the same outside diameter as the cartridge. A short length of any pipe would do. I placed it over the cartridge and tried above two methods.
I repeated the same on the other side.
I drenched all gaps with penetrating oil, let it stand overnight, warmed everything with a heat gun, and tried approach 3. from both sides.

None of above attempts moved the BB a bit. I removed the dust covers from the cartridge, removed the bearing balls, and took out the spindle. This left me with the empty cartridge shell, held by the remnants of the PA mounting rings, stuck in my frame's BB shell.

I tried to saw through the shell of the cartridge by inserting a saw blade and mounting it in a hacksaw.

After wasting two mediocre quality saw blades and lots of toil I gave up. The races of the BB bearings are directly in the shell of the cartridge. The steel around it is hardened through. It is not just surface hardening. I did not want to invest into a diamond coated saw blade. Nor did I have any means to grind through the shell (which would be more than tedious without a power tool that could access the narrow apertures. Don't let the deep cut in the picture mislead you, the cut is only deep where the steel was not hardened.

success

What finally led to success was the following approach:

I chiselled off all of the PA 6 material down to the edge of the cartridge. I applied plenty of penetrating oil in a widened gap that worked as a funnel. Then I heated the cartridge shell with an excellent heat gun and a small propane torch. I used a socket (see 3) as punch and a wood working clamp to press out the cartridge, changing sides repeatedly.

After a few iterations this led to the plastic of the mouting rings to move out a little. I chiselled that off again. And repeated the procedure. Within about 20 minutes I was able to remove all of the cartridge.

method

Based on my experience I suggest the following approach.

A. cut away all of the PA mounting rings that stands out of the BB shell. In particular remove the PA parts that cover the cartridge.

B. remove dust covers from the cartridge bearings. Then remove bearing balls and spindle. Clean the inner part of the cartridge shell.

C. chisel away as much of the PA mounting rings as you can. In particular enough to form a depression that functions as a funnel to channel penetrating oil into the gap between PA mounting rings and cartridge. Fill it up with penetrating oil and let it all seep in.

D. Find an appropriate piston, eg a socket, and press out the cartridge with a vise or clamps. Excellent support on the other side is crucial here. Otherwise you will not be able to apply enough force (without braking the frame).

Repeat D alternating sides. This may wiggle out the cartridge. Apply heat to the empty cartridge shell. The melting point of PA6 is 220 C; the PA of the mounting rings might get soft at a similar temperature. Although, a much lower temperature might suffice if enough force is applied. Be careful not to set the penetrating oil on fire!


How can you find parts for a discontinued bike - in this case, a 2004 Specialized mountain bike

First, try looking for a "scrap" FSR to salvage the linkage from.

Second, BETD have produced aftermarket suspension components for various Specialized, GT, Kona etc designs. They might not have the item you need in stock, but they should still have the files and machinery necessary to make one for you, at a price. http://www.mountainbikecomponents.co.uk/specialized-fsr-04-06-linkage

If you can find some engineering workshop near you, they might be able to copy your damaged linkage. A basic non-adjustable linkage should be achievable using any 3-axis mill.


Name for the thing attached to spokes to remove tires?

Tyre lever (in the UK anyway - WP redirects that to tire iron but to me that sounds more like metal fatigue. After all, they're not made of iron).


Does anyone know what kind of bike this is?

See "J.C. Higgins Girls Flightliner" on this page.  Perhaps not the exact bike, but quite close.  And I think Western Auto was also fond of the "tank" between the bars.


Shimano short cage rear derailleur capacity

As I said in a comment, there are 25+ years of 105 and Ultegra (well, ultegra was called something else back then, but the line has been around for quite a while), so you need to find the right 105/Ultegra you're talking about.

You can find the Product Info at this link.

In 11 speed: The Ultegra RD-6800-SS and 105 RD-5800 SS both have a 28t max. Thus, Shimano doesn't recommend you run a 30t with a short cage. The RD-6800-GS and RD-5800-GS both have a max of 32t.

In 10 speed: The 105 RD-5701-SS has a 30t max.

Note that Shimano has mucked up cable pulls between 10 and 11 speed road, so you can't just put a 10 speed RD in a 11 speed system.

Note that also there may be several RD's under the same group under the same year or # of speeds (e.g. in the Sora case), so you need to look up the particular RD you want to use.


What is the best way to track your mileage, routes and calories burned?

There are several phone apps / web sites you can use. They all have a free mode and a premium mode. A few of them are:

Endomondo
Last time I used this (a couple of years back) it was able to give real time updates and "coaching" on your performance. It can handle many different sports and activities.
MapMyRide
I haven't used this; some other people here do use it. Hopefully they'll say why.
Strava
I currently use this one. The main "benefit" is the social aspect, if you like to see what your friends are doing, and for them to see what you do.

I believe Endomondo and Strava do all that you say you want, and I expect that MapMyRide would do also. They all provide a data export feature.


There are several companies that make masks designed for endurance sports during the winter.  Air that cold can actually cause issues with your lungs when inspired for long periods.  The secret is to find a mask designed to hold the moisture you are exhaling and hold it as a way to moisten and warm the air you are taking in.

Just a plain polar fleece mask can do this, but it can also hold too much moisture in too thin an area and freeze under some conditions.

Another thing to try is a hood with a ruff or edging.  A hood that extends beyond your face can actually create a small pocket of air that your face can keep slightly warmer.  This doesn't work as well in cross winds or such, but it can help significantly.  There is a reason that cold weather cultures have traditionally lined parka hoods with animal fur ruffs.  The ruff extends the area of that air pocket and keeps your face significantly warmer.

The second option will keep your face warmer, but won't do as much to mitigate the effect cold air has on your lungs over a period of time.

UPDATE WARNING PRODUCT RECOMMENDATION BELOW!!

Cold Avenger (https://coldavenger.com/) makes masks of the style I am talking about.  I have no affiliation with the company.  I do own several masks from them and believe they work.  Basically its a traditional polar fleece or windstopper fleece mask with a rubber device around the nose & mouth designed to regulate airflow and retain moisture/heat.


In short, squeaking brakes are caused by the sound of your pads sticking then slipping increadibly quickly, rather than applying presssure to your discs smoothly.

Solution:  Sometimes these problems can be a right pain in the butt.  Sometimes your brakes need time to bed in, sometimes, as you know, your discs just need cleaning, or importantly, drying. But if that doesn't work you need to rough up your discs.  You can get products with abrasives in them just for this purpose, or, less expensively.. I know many people have had success with very fine sand paper.

Give that a try before replacing your discs.


Are braking vibrations a sign of the end of the life of a wheel?

Is there any kind of wobble or unevenness in the rim? There shouldn’t be more than about 1mm of wobble. If there is a noticeable wobble the wheel might simply need truing.

Are the brake pads properly aligned? They should wear evenly over the whole surface.

You can measure rim wall thickness with a caliper gauge. A sign for rim wear is also if you can measure a deformation (change in rim width) between zero and maximum tire pressure.


The K logo is definitely not Kona, my daily rider is a Kona Fire Mountain. KonIA (Konia) maybe? Lower end MTB manufacturer.

BTW my saddle and seat pole definitely NOT Kona. I broke and replaced them myself!


You can avoid this problem altogether with studded tires

The pattern is deep enough so that it grabs quite well on the snow, and the studs give you a very good grip on ice and hard snow. On uniformly flat ice, the grip is almost as good as asphalt.

If the tires are good, you can wear them for all winter season, even if there is no ice. The studs are not very prominent, so the whole tire is still in contact with the road. This solves the problem of having to adapt to weather conditions. At my local bike store they assured me they would last for at least 5 years.

Source: I have tires like the one in the image in the Swedish winter.

PS: here, I have never seen cars them using chains or socks, they have winter tires instead, pretty much a car version of the image. Not all have studs, though.


Anyone seen a hollow crank spindle cut through by an internally-routed derailleur cable?

As clarified in comments, this frame appears to have a 30mm spindle crank with a bare derailleur cable somehow routed internally through the bottom bracket. I surmise that maybe the cable didn’t cut all the way through the spindle, but it might have abraded through the spindle enough to cause a stress riser and later a fracture.
While I haven’t worked on internally cabled frames, my understanding is that most current designs should use full internal housing, I.e. cable housing is pushed through openings in the frame, rather than leaving bare cable. I am not sure how the routing was done on this frame. I am also a bit surprised to hear that bare cable was rubbing against the spindle. If you aren’t routing full housing through the frame, I would imagine there has to be a cable stop to keep the cable under tension. If the frame was designed so that the cable was actually in contact with the BB sleeve, then that does seem like a very elementary error. Basically, I have not heard of this particular issue, and I am surprised by it. It sounds like something might be missing from the story.
While I’m not a frame designer, it does seem like many metal BSA shells with a 30mm spindle would have little room for internal cables or wires. Frame designers may choose to route hydraulic hoses externally at the BB, I.e. the hoses enter the down tube, then exit around the BB, and either re-enter at the chainstay or just get zip tied to the chain stay. One example is the 2021 Trek Domane aluminum bike, photo below from a review by Cyclingtips.

In general, if you have housing against bare metal or carbon, then if the latter is moving, you introduce the risk of fretting. With some current generation frames with fully internal cables/hoses that are routed against the fork steerer, I wonder if this will become an issue over time. At least some bike reviews on Cyclingtips have raised this as a possible issue, although I forget which ones. That could be solved by putting some sort of foam or rubber insulation against the house or cable housing.


What was the rationale for reverse brake levers?

If you look at drawings of old bikes, both types of brake configurations are depicted. This supports the idea that it was merely a design choice with no significant pros and cons over other configurations other than aesthetics. I suggest that it just so happens that builders in the place and time period you cited used this design because it was fashionable.

There is very limited risk here for "catching" unless the rider is literally going through shrubs (and in that situation, catching would be the least concern). Also, bizarre freak-accidents aside, no one is going to be "speared" by a reverse brake handle. Think about what would actually have to occur for that to happen.


If the shoes seem a little too big, try some insoles. Start with the inexpensive ones you can find in a drugstore for $10. That will keep your foot from moving around inside the shoe without having to tighten the straps/laces so much. And maybe the extra cushion provided by the insoles will make the shoes feel a little more comfortable.


Does crank length affect the number of gears a bicycle needs?

Not really. You might want different gears, but probably not fewer.
Shorter crankarms give you less mechanical advantage—they're functionally equivalent to being in a higher gear. So you might want a lower gear range to compensate.
It is common to express mechanical advantage as "gear inches"—this is
(front sprocket/rear sprocket) × wheel diameter
This obviously doesn't account for crankarm length. Sheldon Brown proposed a measure he called the gain ratio that would do exactly that:
(front sprocket/rear sprocket) × (wheel radius/crankarm length)
From this, you can see that wheel radius/crankarm length will typically be about 2. If the denominator is smaller, the quotient is bigger, so for a given set of gears, the net gain ratio would be higher. For that reason, you'd probably want a  proportionately lower gear range.


Change Shimano FC-M431 Octalink crank arms to Shimano SLX

If you would like to change to the FC-M660 cranks you are going to have to purchase a new hollowtech ii compatible bottom bracket and change everything. The octalink is a cartridge bottom bracket and the hollowtech ii is an external bearing bottom bracket. The cranks aren't compatible between the two interfaces.

You can get away without a crank bolt as this only provides pre-tension when securing the left crank arm. Borrow one off a friend when fitting your crank then stick it back on the their bike. It makes no difference once the crank is secured.

If your reason for keeping the chain rings is to maintain a gear ratio you can change out the rings, they both use a 4 bolt 104 BCD so the rings are inter-changeable.


ICEBIKE has a good page describing studded tires, including how to make your own.  The basic process is as you describe: drive screws from the inside of the tire and cover them with something to protect the tube.

Count the knobs and evenly spread out the 25 screws for each side.
Punch holes, from the outside of the tire, into the designated knobs.
Use Robertson bit in the drill to drive the screws in the tire from the inside.
Put liner inside tire and make sure it covers the screw heads
Put a generous dusting of baby powder between the liner and the tube.
Mount tire on the rim (ouch! watch out for the points!)
Inflate to maximum pressure. Put the wheel on the bike (mind the points). Spin the wheel to make sure that the studs don't catch on anything.

I think the takeaways here are that you don't need screws in every tread block and that the screws shouldn't be in the center.  Screws placed in the center of the tread will simply wear down quickly; you really just want them on the outer tread blocks, positioned such that they barely touch the ground when the bike is upright.


How to increase tension of rear derailleur cable

You started with too much slack for the barrel adjuster(s) to take up. Note you have one on your derailer and one on your shifter, and they both do exactly the same thing, so maybe by using both you'll have enough adjustability, or maybe not. It doesn't matter because you don't really want to be maxing them out anyway. You need to re-anchor the cable in a more reasonable spot, and ideally check a few other things along the way.

Shift the shifter into the highest position. (Slackest cable tension, biggest number, the one you get to by pressing the pointer finger lever a bunch of times.) Loosen the RD cable anchor. Pedal the bike so that the chain is on the smallest cog. Take the opportunity with all the cable tension off to visually check that your high limit screw is set correctly. Looking behind the bike, the center plane of the RD pulleys should be that of the right/outer plane of the smallest cog, or in other words very close to but just a little to the right of the center plane as the smallest cog teeth. (counter-intuitive but true, as per Shimano.) Screw both barrel adjusters all the way in, then screw one out one full turn so you have some adjustability in both directions if needed. Using any pliers, grab the end of the cable and pull it taut while tightening the anchor bolt back down. You don't need to pull it hard. You want it to be clamped at the spot that makes it just taut. Unless there are other problems with cable friction, busted housings, hanger alignment, damage to the derailer, etc, the bike should now be approximately shifting, although the shifting will need final adjustment to perform correctly.

But before you do that, since you had problems with excessive slack that started all this, you should do one more step that will reduce and/or eliminate further such issues with "stretch." (Whether or not the cable is physically stretching at all is a contested issue, but it doesn't matter, and either way it's not the main thing causing the slack.) Keeping the shifter in the same highest/slackest position, hang the bike by the seat off a stand or tree or something, and pedal the cranks with one hand while pulling gently on an exposed part of the cable with the other. Once you're in the lowest/largest cog, stop pedaling, stop the rear wheel from spinning and pull hard on the cable. Let go, pedal again to get the chain back down to the high gear, and see if you've created slack in the cable. If so, that's a good thing, because it would have happened eventually anyway. If there is slack then take it out by repeating the above re-anchoring procedure.

At this point, dial in the shifting with the barrel adjusters so that it shifts smoothly with minimal hesitation in both directions, and you should be set.


Can I fit a kickstand to my bottom bracket?

One bolt of that size wouldn't be enough for a kickstand. And, it would have to be a proprietary one and Boardman doesn't say anything about it on their site or product description for the bike. So I don't think it's anything to do with a kickstand.
It could have been added to the shell (which are often a part that's designed seperately and re-used among bikes for different manufacturers) to mount some kind of guide so that the hose and housing can run there where they're more out of the way of the cranks.
It could also be an auxilary setscrew for the eccentric. Some eccentrics fasten solely via setscrews ramming into them. That's a bad design because what happens is they creak and then when you go to change the tension, the bolt wants to sink into its old groove. But, this could have been added to yours to provide additional holding power in case there were ever issues.
Those are just guesses but it's what I see.


Id check out all the connections firstlt then id check for any breaks in the wiring as with it being a foldup bike ive heard of the wiring being caught/streched when folding down etc it could be a simple cause as this if not it almost definitley looks like a failing on the throttle mechanism to me


I looked at some pictures of the bike.

The thing that fits most of your symptoms is that when the FD cable is under tension, it does something to the alignment of the guide plate that the cables are wrapping around, pulling it closer in against the frame such that the RD cable suddenly has tension relieved from it and therefore can't make it up to the big cog, and downshifts with more hesitation.
That you say the problem also exists when the FD cable is disconnected completely is curious, because it's a little like saying the problem happens when there's tension on the cable and also when there's not. Maybe that also misaligns or destabilizes the guide somehow.
Barring other options, I would pull the cranks and BB and see what you're working with in there. It's possible something has happend that has caused the guide to not be supported properly. You may be able to feel it happening by putting a finger against the plate while the other hand shifts the front.
Another thing to look at would be if you adjust the RD to be at the right tension with the FD in the big ring, does it have the opposite problem in the other direction? It seems like it probably would, but it's worth checking.
The other possibility I can imagine is that it has to do with the internal crossing. Usually one would assume this symptom wouldn't be caused that way, because one cable becoming straighter under tension could contort another cable crossing it in a way that increases tension to that other cable, but decreasing the tension is hard to see. But, perhaps they're crossing each other near the contact point with the guide plate in a way where it makes that possible. If you can reverse which cable is crossing over the top, it's possible that could fix it or you could at least learn more. Also, most frames like this can have the housings set up to not cross the head tube, and thus have no internal crossing, but it will come at the cost of much less clean housing lines up front and likely more housing rub on the frame.


I assume you have a mountain bike, as you have a 26"/27.5" fork.

Answering the question in the title:

26", 27.5" and 29" mountain bike wheels all have approximately that diameter with a tire installed. Obviously the actual diameter of a particular wheel depends on the size of tire installed on it.

The rim sizes are 559, 584 and 622mm respectively, as defined by ISO standards. In road bike circles 584 and 622mm rims are also known as 650b and 700c - hangovers from a old French wheel size system.

So on a MTB, you need about 1.5" of extra clearance to fit a 29" wheel instead of a 26" wheel.

Can you fit a 29" wheel on your 26"/27.5" fork? Not really.

Even if you have the clearance, adapters to move the rim brakes are not available (to my knowledge, maybe there is some speciality manufacturer out there).

In addition, bike frame and fork geometry is designed around a specific wheel diameter. If you change the wheel size, the steering geometry will be altered, usually with negative effects.


I recently looked (in France) for break post studs and it was surprisingly difficult to find them. The only place I found it was a bike shop that would sell and repair the same bike I had to repair.

The major things that distinguishes break post studs are the diameter and the thread. There are many models (Is it proper to link to shopping sites that sell those kind of parts to show the kind of models?).


Your bike looks like a 1908 Humber Lady Red Tandem Original Vintage Bicycle. You can look up some pictures and it is very close. I doesn't look like anything has been changed from the original and the previous owners may have customized it a small amount (note the handlebar style) . If this is what your bike ends up being, it could be worth something. Hope this helps!


9 speed SRAM X5 trigger shifter only clicks 5 times and skips through a lotta gears

Your question needs to include a list of all the parts of the drivetrain you use in order to get a clear and precise answer.
However this is most likely an issue of pull ratio incompatibility, especially if you mixed components from different producers, and moreso road components with MTB parts.
Pull ratio differs between producers (SRAM vs Campagnolo vs Shimano), but also between road and MTB components.
You can find here a detailed explanation of how cable pull and pull ratio works, but also helpful tables of pull ratio of various components: Science Behind the Magic | Drivetrain Compatibility

The shifter determines cable pull. Every time you click your shift lever, the shifter pulls in or releases a certain amount of cable. Different brands and different drivetrain speeds (e.g. 9, 10, 11spd) pull different amounts of cable. For the most part, all the cable pulls are uniform for every shift, with the exception of some of the Campagnolo shifters. For example, a Campagnolo 10-speed shifter pulls 2.5mm of cable five times, 3mm twice and 3.5mm twice.
Derailleur shift ratios, also referred to as actuation, are the amount of movement from side to side of the derailleur relative to the amount of cable pulled. Older Shimano derailleurs all have a shift ratio of 1.7. This means that for every millimeter of cable pulled by the shifter, the derailleur will move 1.7 millimeters.

Based on the facts above and the little clues and pieces of information you provide, I can assume you are using a SRAM shifter with a Shimano derailleur, as it fits your description of the problem.
According to the tables in the link provided above, Shimano road components have a 1.7:1 pull ratio, while SRAM MTB components are designed with 1.1:1 pull ratio.
In your case, when using a Shimano road derailleur with a SRAM MTB shifter (trigger, as you call it), this means for 5 clicks on the lever, 1.7/1.1*5 = 7.72 gears will be shifted
A sixth click would mean 1.7/1.1*6 = 9.27, which translates to the chain leaving the cassette.
The limiters on the derailleur will stop the cable from being pulled further to avoid the chain from leaving the cassette (stopping it from jumping below the smallest cassette ring or above the largest one). This is presumably why you only get 5 clicks out of a 9 step shifter.


Simplest and best way to keep water bottles clean and hygienic?

I wash mine in a dishwasher. Mostly because that requires the least effort.

I've had to replace bottles occasionally, I find that eventually the nozzle on the cap starts to leak.


What are the considerations before buying a Full Suspension bike (India)?

There are a few questions to ask yourself. 90% of the time what sort of riding are you doing? Hike-a-bike where you'll repeatedly walk your bike up a hill and ride down, do you commute by bicycle, etc. If you want to use it solely for riding down hills and hucking off jumps and nothing else then maybe get a downhill rig. If you do any other form of riding at all don't get a downhill specific design. Their made to be ski lifted up mountains and then ridden down, that's about it.

From what i read though it sounds like an all mountain or all around trail bike would be ideal for you, something you can use the lockout's on the suspension to get around. Trying to ride up large steep hills on a downhill bike is pretty horrible and tiresome. You also loose a lot of work in the bob of the suspension if you're just tooling around town.

A good quality trail bike with 120-140mm suspension with lockout sounds like it would be right up your alley as far as the type of riding you're doing. The most important part of the suspension system is your body after all. But with 120-140mm of suspension that should be plenty to soak up what your doing but still be usable in other aspects and styles of riding as well.


What are some recommendations for a trainer to get better at going uphill?

Whilst it is true that there are some differences in muscle recruitment between pedalling uphill and on the flat, the main difficulty hills present is an increased power output for a sustained period of time (unless you have a tiny gear of course).  However the main factor it comes down to is fitness - pure power/weight ratio - 200W is still 200W whether its uphill/flat/downhill.

Riders that struggle with hills tend to fall into one (or both) of two categories

Heavy riders that are held back by their weight and lack the muscular endurance to sustain a high power output over a long period
Weaker riders who lack the raw leg power to push the pedals round.

Any of the trainers you mentioned should be fine for your needs - find workouts that work on either improving your lactate threshold, or improving the force you can apply to the pedals at low cadence.
If you want to more closely mimic hill climbing, then put your front wheel on a tall riser block, ride with your hands on the tops of the bars, and concentrate on pedalling smoothly from the hips.

For reference, I use the Fluid² you mentioned, and have seen good gains over the last 12 months doing 2-4 minute big gear intervals (60rpm) to build leg strength and get used to applying force smoothly.


How to trim down using Shimano Tiagra front derailleur shifters?

As per alex's answer and the manual you should be able to trim both up and down. Assuming you have that or a similar model Tiagra (there are multiple variants and I'm not sure all have a trimming option).


On the hub side of the freehub, there should be a Allen headed bolt that you need to unscrew.  Some are 8mm, others are 10mm and some are 11mm.  11mm is a hard to find Allen wrench, so hopefully it's 8 or 10mm.
Put the Allen wrench into the center the freehub and unscrew in the normal direction (CCW).


They're shims for adjusting the disc caliper lateral position, for disc brakes that don't have ISO-style mounting bolts.

Those ones fall out easily and are annoying to deal with in general, so they've been replaced by "shim washers" which are equally thin, very flat washers made specifically for the purpose. Normal washers are stamped out of sheet metal and are rarely flat and often not even either, so using them as shims will leave your caliper at a slight angle and often slightly twisted as well due to the two washers not being exactly the same. In the worst case that will make hydraulic brakes leak.

You can fake these to some extend using washers cut from aluminium cans, but you're better off using proper shim washers despite the price.


Old-fashioned cup and cone type bottom brackets have one adjustable cup, with a lockring. The adjustable cup lets you set the bearing tightness, too loose and there is play, too tight and the spindle won’t turn.

With a cartridge B.B., the bearings are self-contained and the cups are installed to a given torque which is normally pretty high as bike parts go. When the two sides are tightly installed, the spindle will turn freely. There is no finessing or adjustment of either cup required.

The problem of the spindle getting hard to turn when you tighten the cup, therefore, is not normal and indicates a problem. Hopefully it means the B.B. is worn out and replacing with a new one will solve it. I would try this first and see what happens.

As for B.B. sizing, 68mm is the width of the shell, you can only use a 68mm B.B.

The length of 118 mm is the spindle length. It determines the position of the cranks, outboard from the centre, and therefore, chainline. Make sure you understand this term. If 118mm gives the bike the correct chainline, then 118mm is the correct size and you should replace with the same size. Spindle length (118mm) is independent of (any) cup adjustment.

Trying to avoid commenting on a given product, you might ask yourself if the only game in town arrived in that position by being crap... probably not.

Update:
As you have a belt drive, achieving the correct position of the belt is critical, so you must use the correct size spindle, ie 118mm. The eccentric bottom bracket just allows you to adjust the belt tension, the B.B. dimensions are fixed.


Is there a reason why one's calfs would ache on a Turbo or Spinner, but not when riding on the road?

There are likely a few different reasons, but my primary suspicion would be fit. Presumably your road bike is set up to fit your body geometry and angles, where the spin bike is not. Small differences in how a bike is set up can have a big impact on how your body feels while riding.

My n=1 example, when doing higher intensity efforts on the road, I would get high calf cramps after about an hour. When I had a Retul fit done for my time trial bike, the fitter told me that because my feet were somewhat duckfooted, I needed to move to speedplay pedals with longer spindles to allow my heels to drift inward more than my old pedals. Solved my calf cramp problems.


Why are most bicycle gears designed to have so much overlap

Having an overlap between the ratio ranges available with each chainring means you don't have to use your front derailleur as much. Based on your understanding and expectations of the terrain and conditions ahead, you choose a chainring which gives you access to a useful set of harder and easier ratios.

The cassette ratios are spaced to achieve a vaguely consistent %-difference between adjacent gears, with the limits that you can't have fractions of a tooth and for smooth shifting the derailleur's upper pulley has a minimum and maximum distance from the teeth, so the derailleur's geometry needs to move that pulley through an arc that echoes the arc of the cassette.

Having ratios closer together means when accelerating you don't have to "spin out" one gear to avoid getting "bogged down" in the next harder gear, and when climbing you don't lose momentum with a sudden loss of resistance on each change down a gear.

Alternative 1: Internal hub gears

e.g Rohloff 14 speed, Shimano Alfine & Nexave 11,8 or 7 speeds.
Low maintenance but heavy and make removing and fitting your rear wheel more difficult.

Alternative 2: Single-chainring MTB setup with a wide-ratio cassette

10 and 11 speed systems are available with smallest sprocket 9,10 or 11 teeth and largest sprocket between 40 and 50 teeth, for an overall ratio difference from hardest to easiest ratio of 4:1 - 5:1. The derailleur needs to be designed for the steeper cassette angle, of you can use a hanger extender (e.g the GoatLink) to move it down so it clears the largest sprocket, but in the hardest gears the upper pulley may be too far from the teeth to shift nicely.


Rear axle - converting from imperial to metric?

A hardware store is exactly the wrong place to go.

Go to a local bike shop (the older/dirtier the better). They should have the right nuts for your bike in their junk drawer. If not, they can replace the axle in its entirety for you.


This wheel uses internal (inverted) spoke nipples.

You need to take off the tire and tape and true from inside the rim, as in the picture below:

(Source: Park Tool SW-15 documentation)

The tool will be something like Park Tool SW-15/16/17/18/19. You'll need to look up what the particular right tool is for this job -- I don't know which one is the correct tool.


Kryptonite Flex frame bracket slides around a lot

I am going to conclude that this design is poor, is overcomplicated, it only has a flimsy piece of rubber for a strap which doesn't meet with the other elements (namely, the nylon strap and the metal fastener which sit around it) properly in order to achieve a consistent grip, and the rubber doesn't last long. The rubber leaves marks all over the frame as well. I can invent a solution myself that will work better than this Kryptonite thing, which imo only suits bikes that you aren't worried about scratching and aren't going to ride too hard. Any solution needs to mount to at least two tubes on the bike to ensure the lock is held with sufficient rigidity.

The rubber will perish inevitably after a few months outside and then it will be useless, and even before then it still didn't work entirely satisfactorily for when you ride the bike hard up a hill, where it will nudge slightly out of whack, sometimes knocking the knees.


I keep getting flats right at the valve!

As Paparazzi said: make sure the valve goes straight through the valve hole, i.e. perpendicular to the tube. This is likely the solution, but I've seen it happen that even after properly aligning the valve it somehow wasn't aligned anymore after a couple of rides. Which resulted in the bottom of the valve getting cut by the edge of the valve hole in the rim. Which means the tube did not (or not completely) stay in place, i.e. at least a part of it shifted with respect to the rim (and possibly the tyre, hard to tell). As far as I know two things could cause this, first one more likely than the other:

if your tube diameter is bigger than your rim and you force it in the tyre anyway, there whill be one or more wrinkles in the tube. If this wrinkle is near the valve, it's not too hard to see that it's possible that under stress the tyre can move a bit, resulting in an unaligned valve, resulting in cutting
even with a proper tube diameter, if your tube sticks to the tyre around the location of the valve (caused e.g. by lack of some antistick agent like chalk, water getting in, ...) and there is quite a lot of stress on the tyre, the tyre could in theory move with respect to the rim and drag the tube with it. Can, as far as I know, only be caused by skidding or incorrectly landing jumps or so: unless the tyre is the wrong size, it requires sheer force to rotate it over the rim.


Can I install an upright handlebar (curved towards me) on a touring bike?

is this a good idea? Or is there some danger that I'm not aware of?

You can safely install different shapes of handlebars on all bikes (when done properly).  If you want to keep your current stem, make sure you buy a handlebar with the exact same diameter as the old one (this is exact to a fraction of mm).  Or if you want/need to replace the stem make sure you buy a stem that is compatible with your fork.

Edit after photo has been added:

I am quite confident you can safely replace these handlebars with "Dutch"-style bike handlebars.  The most complicated would be to make sure you can safely use the brake levers.  Adjust the angle by rotating the lever before tightening it down.  Most brake levers allow to adjust the reach of the lever, in case you have trouble comfortably reaching for them.  If you don't feel comfortable making these adjustments yourself, it would be best to have a bike shop do it for you.

Good luck!

You didn't provide much information on what handlebar you have now.  Nor what brake levers and shifters are fitted on them.  And this is where the costs might go up quite a bit.  For example, if you currently have drop handle bars, your levers are not going to (safely) fit on the handlebar you want to use.  So then you need to replace the brake levers and shifters, keeping then in mind that you need to buy levers and shifters that are compatible with your current brakes and derailleurs.


Looking for an alternative to the Speedlifter Twist / quickly rotate handlebars solution

There is the n'lock: Nlock. Which appears to be in production and come in a variety of sizes to fit different bars.  I have no actual experience with them but it looks like it meets the requirements you set out.


I believe your bike has a double crankset with 50-34 chainrings.

The general advice is to attempt to avoid cross-chaining, i.e. avoid the big ring and biggest 2-3 cogs in the rear, and avoid the small ring and smallest 2-3 cogs in the rear. There is actually some empirical testing that shows that these combinations create higher friction in the drivetrain, and they likely wear the chain and cassette out faster also.

I'm pretty sure that with almost all groupsets, you can expect the chain to actually shift to all the cogs. In the small ring and smallest 2 cogs, the chain rubs against the front derailer cage quite noisily, but the rear derailer does actually make the shift. In my experience, big ring and biggest two cogs are slightly noisier, and you can often trim the front derailer to reduce the noise (that is, the left shifter often can actuate a partial shift which moves the cage slightly, but not enough to go to the small chainring).

Practically speaking, it is fine to leave the chain on the big ring most of the time, and to shift to the small cog when climbing significant hills. I find that at most normal solo riding speeds, a 50t chainring leaves me in the middle cogs on the cassette. Thus, one rubric I use is that if I hear the chain rubbing the front derailer slightly, I'll downshift in the front (i.e. shift to small chainring, which decreases the gear ratio) and simultaneously upshift in the rear (i.e. shift to smaller cogs, which increases the gear ratio). With the small rings on modern setups (i.e. 34t or 36t), many riders will probably be in the smaller rear cogs on flat terrain, which is not optimal for reasons discussed above.

In the past, when typical gearing was 53/39 and cassettes had tighter ranges (e.g. 12-25 or 12-23 in the rear), riders may have been advised to leave the chain on the small ring most of the time. I certainly recall being advised to do this by people in my cycling club. I believe it was conventional wisdom that you wanted to learn to spin the cranks smoothly, at a relatively high cadence. I don't know that there was a lot of empirical basis behind this advice, i.e. it could just have been fashion. Most newer cyclists will pedal at relatively low cadence, and will probably work their way up to a more optimal cadence gradually.

NB: please read what Adam and Argenti said about overlapping gear ratios between your two chainrings.


What is randonneuring? How to get started?

The short answer is "marathon cycling".  Others have called it "touring with time limits".

As a sport, randonneuring is based on rules laid out by Audax Club Parisien (ACP).  Rides are known as "brevets" and are organized by local clubs.  They may have slightly different interpretations, but you can count on brevets being basically the same around the world.

I won't go into all of the gory details, but here are some of the highlights:

Randonneuring is a non-competitive sport.  You get credit for finishing a ride within the time limits, but there are no rankings, no awards for coming in first or setting a great time.  Some ride just to see if they can finish, others are trying to set new personal best times.  This means that you can team up with a group of similarly paced riders and help each other make it to the finish, which is very helpful when you're new to the sport.  All the riders I've ever met have been very generous with information, tips and motivation during brevets.
Riders must be self-sufficient.  You're riding on regular roads without a sag wagon or cheering throngs of spectators.  Some brevets might have a lot of volunteers, so there may be food & water at some of the checkpoints.  Other rides might only have someone at the start & finish.  In between, you're on your own so you need to be able to sort out mechanical problems and take care of food & hydration.  Being prepared is essential since some routes can send you through very remote areas.
Controls (or checkpoints):  you have to follow the specified route (instructions given out at the start, or possibly in advance) which passes through a series of controls.  At each control, you need to get proof of passage.  Typically this means getting a control card signed or stamped.  Sometimes this might be done by volunteers, other times it's a bewildered 7-11 clerk or cafe owner.
Time limits:  there is a time limit to make it through each control, including the final (finish) control.  The limits are generous and are based on maintaining 15km/h for rides 600km and under.  Keep in mind that this includes rest/food breaks, mechanical problems etc so you need to average above 20km/h to keep ahead of the cutoff times.
Distances start at 200km.  A basic series would be a 200km, 300km, 400km and 600km brevet (depending on your club they might be spaced 2 weeks apart).  So for a 200km you have 13.5 hours to finish; 600km has a 40hour time limit.  It's a running clock, so the longer distances will involve plenty of night riding (on a 600km it's possible to build up enough of a time buffer for 4hrs of sleep, more if you're really fast).  Other distances include 1000km and most of the premier events are 1200km (90hr limit, typically), including Paris-Brest-Paris.
Paris-Brest-Paris (PBP) is the biggest event on the randonneuring calender.  This is a 1200km event which draws thousands of riders from around the world.  It only runs every 4 years, and 2011 is the next one.  Participation in randonneuring clubs usually spikes during a PBP year, so it's a great time to get into the sport as there will be many other new riders.

My favourite resource is the BC Randonneurs website (very biased, since I'm a member).  The links at the bottom of the page go into more detail on what I've covered.  Randonneurs USA will probably be useful if you're looking for a US-based club.

If you love riding, enjoy challenges and are very persistent (read "stubborn") than I'd highly recommend it.  Most clubs run shorter rides called "populaires" which are open to non-members and give people a chance to try the sport with only a 50-100km committment.


How do I tell what needs repaired/replaced/cared for?

Clean and oil the chain regularly.  A "chain washer" (about $30) is good for cleaning while making minimal mess.

Since you have to store your bike outside, use "wet" chain lube (at least in rainy season).

Buy yourself an inexpensive "chain wear indicator" for about $10.  Replace the chain when it's stretched to about 0.8, and, when you replace it, check your cogs to see how worn they are.  (The Park Tool site likely gives some hints as to how to check for cog wear.)

Visually check your brake blocks every now and then (assuming rim brakes), and replace before the metal part comes close to touching the rim.

Occasionally inspect your cables for fraying or excessive rust, and replace if indicated.  As the bike is stored outside, occasionally put a few drops of lube on the cables where the inner cables slide into the outer housings.

Occasionally inspect your tires for wear, and for cracks in the sidewalls that indicate they are "drying out".  (And, of course, get a good "floor pump" with built-in gauge and check your tire pressure at least weekly.)


Brand new Shimano BB-UN300 hard to spin when drive side is fully torqued

It is possible for BB shell distortion from welding to cause excess friction in BB cartridge units. Usually this is accompanied by roughness screwing in one or both parts of the cartridge. In those cases, chasing and facing the shell typically eliminates the issues, and there's not much else that can be done.
What you describe could be the normal friction of a new lower-end cartridge, which will tend to get better in use, or it could be a symptom of the above. Doing a test with a crank as you describe may make it harder to see what's going on, because the crank creates so much leverage. I would install the cartridge in the normal way and then test how freely the spindle turns by hand. A little friction is okay but it shouldn't be much more than that.


Cantilever brakes for older narrow fork bosses (55mm)?

What brake pads did you try? I had a heck of a time getting modern Tektro cantis working on a fork of mine until I used Kool Stop Thinlines with the spacers set for in their thinnest configuration.


What skills/drills should I learn to descend faster and more confidently? (for mountain biking)

I happen to be one of those who attract new riders into the sport, and have given the basic training to many people. Here is a brief of what I try to teach them:

Riding position
Be ready to react
Have your bike properly tuned/fitted
Scan the terrain(Look forward)
Use a proper braking technique
Never get to the extremes
Grow progressively
The most important: never stop trying/practicing!

The attack position

The position that works best for me is slightly raised from your seat, knees bent, lowered torso with elbows bent. Feet at the same height with the dominant foot on front.

Ready to react: Your hands should be firmly gripping your handlebar, but not tense. One or two fingers ready to activate brakes. Choose the fingers you want on the bar based on whether you get the best grip. It is a little more important to control the handlebars than to freak-ly squeezing the brakes all the time. This is critical over rock or roots sections that shake the bike in all directions. You need to hold those bars captain!

Besides this, your elbows and knees should be slightly bent at all times, giving you chance to extend or contract them as needed, so you absorb terrain irregularities as you pass them over. It is like moving the bike around you (up/down, front/rear, right/left). This is why I do not recommend to sit way back arms fully stretched: In this position you have no freedom steer or to lower the bike while entering a hole or a "step down". An easy way of thinking is this: Your arms and legs are "your" suspension, you want to be positioned rather in the middle of its travel.

Properly tuned

You should tune your bike as best as possible. This includes brakes and suspension (if any). Your brakes should be at best performing shape. This is a whole complete subject, so I wont go deeper on this, but basically, they must have won your confidence. The levers should be placed where you can be more effective to apply the brakes. The distance between the brake lever clamp and the handlebar grip should allow you to actuate the lever with the index finger, the middle finger or both. The "reach" is how far is the lever from the grip when brakes are nor being applied. This distance should make comfortable for you to grab the lever, not too far that it is difficult, not to close your fingers get tangled with it. Also, when you apply the brakes, the lever should go down to the position where your fingers feel stronger doing so.

The suspension should be properly adjusted too. The two main adjustments are preload and rebound speed. Preload is how "stiff" is the suspension and it determines "sag" Sag is how deep the suspension travels on rider weight. A proper amount of sag allows the wheels to travel down when required. When you have too little sag your tire looses contact with the ground too easily and you loose control. Too much sag makes the suspension makes it easy to bottom down, hitting the far end of the suspension travel. This may also lead to loss of control or another failures.

The rebound speed is how fast the shock absorber returns after hitting an obstacle. too fast and the bike will feel shaky (you'll feel no confidence) and maybe it will bounce off the ground loosing traction. Too slow and it will feel like getting stuck after a bump, effectively it will not be ready for the next bump if it comes too quickly. The correct intermediate position depends on your riding style and the particular terrain characteristics.

There are other adjustments that can be made, but they vary a lot model to model, brand to brand, so the best approach is to refer to the user's manual.

Scan the terrain

Look forward, never look down to the tire. The faster you want to go, the further up the trail you must look. Scan the terrain and look for the best line. Choose areas where you have more traction, or surfaces were is better/safer to brake. Dry solid rock or compact ground are commonly good options. There is a saying that the bike will go wherever you are looking at, so, focus on your route, choose where you want to go and stay there! It is common for a rider to stare at that rock sticking out, having fear of it, and... crashing into it. Avoid that behavior, don't stare at obstacles, but trace your path around or over it, and focus in that.

Braking technique

The most important skill regarding brakes (IMHO) is knowing when NOT to apply them. Braking is instinctive, as soon as you feel danger, you'll squeeze the brakes. But there are a lot of situations where it's best not to. First of all, never squeeze the levers quick and hard: this makes you lock up your tires and loose traction. You have to be gentle. Usually you have to release your brakes when going over wet roots, slippery rocks, etc. Specially you should release your front brake just before hitting a rock or a hole, so it will be free to roll over the obstacle and thus avoid being tipped over the bars.

I recommend to use BOTH brakes at the same time. You'll find a lot of divergent opinions about this but, I've found that each brake serves a purpose. The rear brake alone can slow you down just a bit,  but it tends to straighten the bike while over slippery surfaces or loose sand/gravel, a little like the rudder on a plane. The front brake can stop you down, but it tends to trow you to the front. It is vital to learn to brake without locking up the wheels, specially during a turn. If you are focused on where you are headed, it is more dangerous to over-brake than to brake a little less. It is also important not to hold the brakes all the way down, thus avoiding overheating, which can lead to brake failure.

Never get to the extremes

Never adopt extreme postures. Not to far back, not to low. I made such mistakes at my beginnings, but I had to correct those. Stretching to be too far back lessen your ability to maneuver. Using the seat too low for "improved stability" also puts your legs in an awkward position that does not let you negotiate ups and downs. While going downhill over the roughest section you should be off the saddle to avoid hitting your spine anyway.

Grow progressively

Never try too hard to get up to your buddy's riding level, do not take risks that are beyond you skills. Go a little at a time. Practice a lot. Find the way of practicing the obstacles over and over. Grow in technique before you grow in speed. Each kind of obstacle requires specific movements, as you learn them, you need to build "muscular memory" before taking it to another level, so be patient, but never stop trying/practicing. Be humble and practice even what you feel you've mastered. When you conquer an obstacle/jump/drop etc. for the first time, try to go back and do it again, and again, and again...

You may have already built skills in some of these areas, but each one of these points has way more to discuss about. I'll be happy to go deeper in any subject if I find questions directed more specifically towards any of them. My credentials: I am a cross country and downhill rider with a few podium positions at local DH races ;) .


What is the process of adding a light to a Yamaha PW equipped ebike?

Okay, so I did some research into this and here's what I found:

The Yamaha drive offers enough power for many, but not all, ebike lights to be connected. For example, Supernova M99 Pro won't work -- that's my favourite bike light. But lights like the Lupine SL S or Supernova M99 Pure work just fine.
To install the light, one needs to remove the protective plastic cover and undo two out of three bolts that connect the motor to the frame.

So I've ordered the light and the Light Cable to connect it to.

Update: did the entire installation process, here are the approximate steps I had to take.

Step 1: remove motor cover. Also the step where I get unpleasanly surprised that the bottom plastic motor cover has a hole in it. I wonder what idiot thought of that... this is where all the dirt and mud will accumulate. This is insane. Reminder to self: tape it over. Haven't seen this level of insanity from Bosch.
Step 2: unscrew two out of 3 motor bolts, loosen the third... also the step where I realize that those bolts are tightened with 22Nm of force. I did not, do not, nor will I ever own any instrument with a hex key that can apply 22Nm of force. This seems excessive and downright cruel and no, Bosch does not do anything as evil. Consequence: had to improvise a long handle for a hex key. Pretty sure I did not tighten it back to 22Nm, but I don't care. It's not going to fall off.
Step 3: connect Bosch LightCable to the motor (there's no ambiguity regarding the port or direction) and run it to the handlebar. This was also annoying because Haibike has these black plastic plugs where the wires came out and naturally, there's no space for extra light wire. Had to clip away some plastic.
Step 4: connecting wire to Luping SL S light... where I found out that Lupine does not mark the type of screwdriver you need for opening up the light. Furthermore, I watched their video where they suggested a Torx T5, so I ordered one, waited two days only to find that the light actually opens with a T6. Insanity! Also, they ignored my support request :( and when a manufacturer does that, well, they get blacklisted in my book.

To sum things up: the process of light installation is rather annoying, but manageable.


Will brand matter between a rear derailleur and front derailleur?

I believe you are referring to the shifter, not the front derailleur. The shifter connects to the derailleur with a cable
Sensah Reflex is an 8 speed system with components designed to be interchangeable with Shimano 8 /9 speed.
http://www.disraeligears.co.uk/Site/Sensah_Bicycle_Components_2020_page_6.html
Probably the Sora RD is slightly better quality, not because it is 9 speed but generally Shimano have better manufacturing standards and shifting quality than most other brands, though Sensah doesn't seem to be terrible at all.
There is no difference between an 8 speed and a 9 speed RD so that part is fine. (Often a 9 speed is a more expensive part and made from lighter materials , but that's all)
Given that you still have shifting problems and have identified that the derailleur hanger is bent, it is obvious that that is the source of your problem. So find a replacement derailleur hanger, keep your Sora RD. If you can't find a replacement hanger perhaps you can straighten it, but given your mechanic has failed to do so replacement seems a better option.
https://www.parktool.com/blog/repair-help/rear-derailleur-hanger-alignment


Olympia bicycles are as good as any, and the company has been doing for about 100 years longer than any you mention.

Having said that Olympia produce good bikes, they have a different brand for pro-level equipment: Scapin, one of which I am privileged to ride.

I gave an Olympia to my brother-in-law, three years ago. He's been riding it 500 km per month ever since without problems.


That sounds like 3/8 inch.

Take the hub to a bike shop, they'll be able to pick out a compatible axle for you.


Do Master Link pliers help with SS / fixie chain assembly?

If you're looking for a way to get the chain off without loosening the wheel then this won't help you. This tool require there to be enough slack in the chain to pull two links together. I'd say the links move about 5mm in order to break the link. I would recommend having this much slack in the chain normally.

What you want is a 3 piece master link that uses a c-clip to hold it together. These don't require any slack in the chain to disassemble. They seem to be more common for 1/8" chains though.


There are two basic adjustments that apply to all types of rim brakes (v-brakes, cantilevers, calipers):

Tension:
The cable tension from the brake lever to the brakes adjusts how responsive your brakes feel.  Tighten it up and both brake pads will engage sooner and the braking action will be harder.  Loosen it up and braking will feel spongy and you may not get enough power.  Normally you want to add tension; removing tension is only done when you put on fresh pads or if you set the tension too tight.  Adding tension periodically is important since your pads wear down over time and the cable stretches a bit too.

The easiest way to adjust the tension is to use a barrel adjuster: they're usually on the brake lever or the brake or both if you're lucky.  Add tension by turning the adjuster counter-clockwise (looking at it from the side where the cable housing goes in).

But whenever you adjust tension, you need to fix...

Balance:
This controls how far each pad is from the rim.  Adding tension will pull both pads closer to the rim, but usually one will move more than the other.  So by adjusting balance you can move the closer one further away and the other pad will do the opposite.  You want to balance the pads so that they're about the same distance from the rim and engage at about the same time.  If it's skewed (like your brakes) then you won't get as much braking power.

For v-brakes and canti's there's a spring inside each brake arm.  You can adjust the spring force by turning a small set screw on the side of the brake arm.  Screwing it in (clockwise) will pull the arm away from the rim (which pulls the other one closer).  It's best to adjust the two arms together:  screw in the closer arm first by half a turn to start, and screw out the other one by the same amount.  Check the balance and then repeat as necessary.

For caliper brakes (road bikes) there's normally just one set screw to adjust.  Turn it to see which way the brakes move.


XT 11 speed derailleur (RD-M8000-GS) rubbing 46T cog with b-screw all the way in?

As the comments suggest, you need to install the chain to adjust the rear mech. You can test this yourself by manouvering the shifter to mimic having a chain and you should notice that the mech cage can move up and down.
The proper intaliation process is:

Install derailleur with b screw half way on the hanger
Install chain, length calculated using the manufacturer's instruction
Adjust b screw according to manufaturer's instructions
Fine tune the shifter/ cable
Re-check the b screw as the fine tuning of the cable can change it

On a side note, I tried this same setup, but with xtr 11s mech and xt 10s shifter, and the middle gears where always off and a little jumpy. So I just bought the 11 shifter and I wouldn't recomment mixing it.
Whether the mech is direct mount or not, shouldn't affect this, as long as the mount is not bent or damaged.


The Schwalbe Marathon Plus (not just the Marathon) is widely regarded as the most flat-proof tire out there. It's also heavy and expensive, but if your priority is avoiding punctures, I don't think it can be beaten. ISTR reading about a round-the-world rider completing 50,000 miles on a pair without a flat.

Specialized Armadillos are not, in my experience, particularly flat-resistant, although there might be a beefier version than the one I was riding on. I have no experience with the Gatorskins.

Anyhow, there are definitely differences between flat-resistant tires. There are even differences between Schwalbe Marathons variants.


Is the Shimano 2303 crank arm and the 2300 crank arm the same?

Not a specialist on this, but I assume that the 2303 (being a triple crankset) would have the chainline aligned to have the middle ring right on the center of the cassette, while the 2300 would probably have middle of the two chainrings in line with the cassette. You could probably get bottom bracket with a shorter spindle to move the two remaining chainrings closer to the frame to make things line up perfectly. Be careful that the chainrings and crank arm do not contact or rub on the chainstay when using a shorter bottom bracket.

As far as your levers go, you will probably be fine, as both the 2300 and 2303 are build for road shifters, and there's no different between road and mountain groupsets anyway in the 2300 level of components. For instance, my bike uses 2300 shifters with a deore rear derailleur.


Preventing lamps being stolen / thieves' motivations

I've never had a problem like this with dynamo powered lights. While thieves seem to be interested in clip-on lights, they don't seem interested in lights that need a wrench to remove.

Of course, adding dynamo powered lights means adding a dynamo first, and it's important to take either a hub dynamo or a good bottle dynamo. The vast majority of bottle dynamo models is utter crap! The added advantage of dynamo powered lights is that you cannot forget to charge them, and they'll serve you well should you decide to ride through an entire night...


Will there be compatibility problems for crankset and bottom bracket for vintage motobecane?

Old Motobecanes are all over the place with BB threads. There are large numbers of them each with French, ISO/English, and Swiss. (Swiss may seem odd, but the deal with it is that it's the same 35x1 thread as French but with a left-threaded drive side cup, to prevent loosening. So it's kind of a natural progression from French, although I don't know the exact history with Motobecane using it.) Many but not all BBs have their thread type inscribed on the outside of the cup. I'm sure there's also a heavy correlation with where in the world the bike was originally sold - i.e. if it was for the domestic market it's probably not ISO.


While price is not the defining factor, there is no doubt that it is a key indicator of quality.

List of Groupsets

Below is a list of the three largest manufacturer's groupsets for Road and MTB applications.

Each manufacturer's offering is arranged in descending price/quality.

The number of sprockets of the cassette in each groupset is shown in brackets.

The total number of gears is determined by this number multiplied by the number of chainrings, for example a bike that has a double chainring and a 10-speed cassette has 20 gears, although some of them overlap.

Road:

Shimano - 2009

Dura-Ace 7900 (10)
Ultegra 6700 (10)
105 5700 (10)
Tiagra (9)
Sora (9)
2300 (8)

Campagnolo - 2009
Super Record (11)
Record (11)
Chorus (11)
Athena (11) - new for 2009.
Centaur (10)
Veloce (10)
Older Campagnolo groupsets that were discontinued from 2009 are the lower-end:
Mirage (10)
Xenon (10)

Campagnolo also offers 3 triple chainring offerings for steep hill-climbing:

Comp Triple (10)
Race Triple (10)
Champ Triple (9)

SRAM - 2010

In 2006, SRAM released two groupsets for racing bicycles, aimed at competing with Shimano and Campagnolo's offerings. The top SRAM groupsets are called 'Red' and 'Force', being the pro-level and amateur racing level lines, respectively.
It is worth noting that SRAM has trickled down its technology at an accelerated rate to compete, and that each year production groupsets feature several upgrades, some years more than others. In 2010 SRAM have released a new groupset, Apex, which is aimed at a more casual level.

Red (10)
Force (10)
Rival (10)
Apex (10)

MTB/General

Shimano - 2011
XTR (10)
Saint (9)
Deore XT (9/10)
Hone (9)
SLX (9/10)
Deore LX (9)
Deore (9)
Alivio (8/9)
Acera (8)
Altus (8)
Tourney (8)

SRAM

XX (10)
X0 (10)
X9 (10)
X7 (10)
X5 (9/10)
X4 (8/9)
X3 (7)

SRAM also offer parts under several different marques as they've slowly bought out several smaller, specialist bike part manufacturers. These include:

Brake systems - Avid
Cranksets - Truvativ
Mountain Bike Suspension - Rock Shox

SRAM are phasing out 3 ring front chainrings in their MTB range for a 2 front chainring, 10 sprocket rear cassette setup, commonly found on road bikes.

Specialist

There are some groupsets which are designed for a specific purpose (track cycling, downhill etc.). Some are just partial groupsets which are intended to be used with other groupsets.

Shimano Dura-Ace Di2 7970 - (10) - electronic shifters and derailleurs intended to be used with regular Dura-Ace 7900 parts (cranks, cassette, chain, bottom bracket etc.)

Shimano Dura-Ace (track) - (1) - Track bikes

Campagnolo Pista - (1) - Track bikes

Campagnolo Time Trial - (N/A) - Time Trial components with bar-end controls, chainrings with oversized toothing and super-light brake levers in composite material.

Shimano Hone - (9) - Enduro and Freeride applications

Shimano Saint - (9) - Downhill and heavy-duty applications

The Shimano Nexus began as a internal hub only and has slowly grown into its own groupset including a higher end internal hub (Alfine, previously Nexus 'Redline'), chain, shifters, cranks, brakes and calipers.

Shimano Alfine - (8) - Internal (planetary) hub gearing, hydraulic disc brakes or mechanical calipers

Shimano Nexus - (8) - Internal (planetary) hub gearing, drum brakes or calipers
[edit]See also

This information was copied wholesale from the linked Wikipedia article.


Changing one of the chainrings on SR Suntour NEX crank?

The Suntour NEX cranksets are marked as "Interchangable Chainring Design" by Suntour, while the XCM's are marked as "Full Interchangable Chainring Design".

This means that you can replace the big ring on a NEX crankset, but the middle and small ring are one piece. So, if you want to replace the middle chainring, you have to buy a whole new crankset (or somehow source the middle and small together). Given the NEX is a fairly low end part [~ 30 USD], another crankset is likely a better idea [ You can pick up a Shimano crankset or similar with all chainrings replaceable for around 50 USD ]. Note that  a new chainring would have been likely ~20 USD if you could have replaced it.

Also note that you can go a good while with a "worn" crankset provided the teeth aren't mucked up too badly (e.g. bent), so "suck it up and deal with it" may be a good option depending on what state the crankset is in.

The crankset replacement procedure is here - you may need some tools you don't own.


If your problem is just that you're heavy, remember that things have changed significantly in the last 10 years. Bike manufacturing has taken up new materials and technologies now, so we have high-strength alloys (of steel as well as aluminium) and a lot of parts are stronger or lighter than they used to be. It's likely that 14mm 10 years ago is no stronger than 12mm now.

What you could easily do is a custom frame using MTB through axles and disk mounts with matching MTB hubs (singlespeed hubs, of course) laced into 406 wheels. It might end up being a $US2000 BMX, but it could definitely be done (I build my own bikes as a hobby because I end up in this position - what I want isn't on the market, so I build it myself). It would be cheaper if you could buy a trials bike with disks, but that might not be strong enough for you.

Disk hubs are very common and available in a variety of hub/axle sizes, as well as being fairly straightforward to make if you have a CNC milling machine (so many machine shops will be able do it for you). The question then becomes how much you're willing to pay. Unusual sizes and combinations are likely to be more expensive.

Custom framebuilders make and sell disk caliper mounts to be welded or brazed on, they're not expensive and buying some will save you a bit of hassle. But I suggest getting one that includes the dropout to simplify alignment and position.

14mm hubs with disk brakes are something I don't think I've seen, 14mm strikes me as more a flatland thing for people putting huge loads on the axle-mounted foot pegs rather than being needed for the actual wheel. So you may never find a disk+footpeg hub. Is 12mm an option? I'm pretty sure I've seen 12mm axle hubs with disks. Sites like BikeRadar have opinions that might help you decide what's worth looking for

Also, I don't think you'll find bolt-on adapters to do what you want. I'm not sure they could even be made as the forces are quite large by bicycle standards and things have to be made specifically to deal with them. I suggest looking at trials bikes because they use small frames, 406 wheels and disks for the most part. You could almost certainly get a 406 size front fork and fit that to your frame, for example, but you'd likely end up spending more money that way than just tweaking a trials bike for BMX.


Cross bikes are generally ok for less serious trails where you're looking for decent speed, without the need for serious climbing, suspension and traction.

You've got more clearance on a cross than a road bike, but the frame is a similar size and they've generally got 700mm road size rims, so they aren't as maneuverable as an MTB. They generally don't have suspension. Tyres are fatter and with more tread than a road bike, but they'll normally only get to about 32-35mm width - MTBs will go wider. The gear ranges reflect this too - you'll be able to go faster at the top end, but the lower end gears to tackle the serious inclines will be more favourable on MTBs.

In general use cross bikes are great for road use with a bit of off road, where MTBs would be the other way around - especially if you're going to be going seriously off-road.

The 'real cyclist' answer is to get both. After all, you'll always need another bike, right?


This obviously depends entirely on your fitness level and your experience on a bike.

I will say that of all typical 15km rides, the ride between Delft and Rotterdam would likely be in the bottom 5% of difficulty, along with most of the rest of the Netherlands. I haven't done that route specifically, but from my time cycling through the Netherlands I can say that your ride is virtually certain to have no hills, cooperative traffic, and well-signed cycle paths. Unless you are grossly out of shape or have a physical condition that makes cycling inherently difficult, this is likely to be one of the easiest 15km rides you could possibly do.


The brakes are mechanical brakes. Normally (I don't know this brand) the brake lever moves one side of the pads only and pushes the disc against the other. When properly adjusted the disc moves very slightly into the non-moveable pad.

Normally the pad that move is the outboard pad, and the fixed one is the inside pad. To adjust you probably need to unwind the inside pad 1/4 or 1/2 turn, and maybe readjust the calipers.

Refer Here for some good instructions.


How to tighten gates belt drive on Focus planet 8

It's hard to tell from your pictures, one from the side would be nice.  I did a search and came up with the following picture.

If this is what your bike looks like, then you need to loosen the two bolts I've labeled on both sides (4 total) and slide the wheel back until the belt is tensioned correctly. Make sure the wheel is straight and even on both sides when tightening everything back up. From looking at your pictures, it also looks like you should tighten the bolt on the inside of the chainstay where you've circled in red to prevent the wheel from slipping.


Chain slipping on smallest cogs (bigger chainring, new chain)

You can play around with chain-wrap and cable adjustment all you want but this problem is 99.999% of the time caused by wear on the cog's teeth. Ask your LBS if they can sell you only the cogs you need. It may seem like the cassette isn't old enough to justify being worn out, but that's a 10 tooth cog you're talking about, a tiny piece of thin metal responsible for handling all those watts we put down! ;) Plus, considering you made the switch to a larger chainring, I get the impression that you were doing a considerable amount of riding in your highest gear, accelerating the wear it experienced.


What's a good bike for daily use in New Orleans? A flat city with lots of potholes and bad roads

Better yet, look at a 29'er. Like this one.from Kona, Single speed, rigid, fat tire MTB. Run fat tire slicks, and it's a great commuter. The lack of shifting works well on flat ground, with the right gear choice (very personal decision), and the fat large tires roll well and comfortably. MTB durability means rough roads might as well not exist.

There are many bikes like this, and while i like the Unit 29'er linkd, I'm recommending the idea, not the particular bike.

As far as branding, that can be fixed with judicious use of tape, spray paint, and stickers.


That's an indication of possible crash damage, because the brake arms have bent and distorted their mounts.  However your photo shows rear mounts which are rarely damaged this way.

It can also happen if someone deforms the mount by using the wrong bolt, or over-tightening it and deforming things.

You may be able to use a small automotive bearing puller to pull the brake arm off.  A couple of flathead screwdrivers can help provide leverage.

Another moderately good help is to warm the area with a hairdryer on high.  This may be hot enough to damage plastics, but shouldn't damage paint.  If the frame is carbon fibre or  aluminium alloy then don't try heat, but it works nicely on steel.

Last resort is to cut the brake arm off using a dremel and small cutoff wheel.  Its very hard to avoid damaging the mount posts though.

Crazy thought - have you tried backing off the spring tension adjust screws?  Not all the way out, perhaps 10-12 mm.

If the tension springs are somehow locked in a groove or something, this might help.


Does it make sense to complain to companies about bad driving?

Anecdotal evidence I have heard is that in a lot of cases complaints actually do have an effect, particularly if the company is a large one.  All complaints have to be followed up and while you may not hear back from the company, management does speak to the drivers involved.  Whether this has a positive effect or just creates resentment with the driver, I don't know.


I need help identifying used MTB tire sealant

The final result was "don't do that" (where "that" was to try to identify and match the existing sealant). Per advice in the comments I cleaned out the remaining liquid sealant (and the crud where the sealant had pooled and hardened during non-use), cleaned the inside with isopropyl alcohol and a lint-free towel, and then set the tires up with the sealant I have on hand (Stans). They have been holding pressure and riding great.


Pedals with largest outside platform area

Something like the Crank Bros Stamp pedals might work. The large version are recommended for people with size 10-15 feet, and they also have metal pins that stick out allowing your shoe to grip onto the pedal better.

It might make sense to go to a local bike shop to see what help they can give you. Seeing the pedals in person might let you know if they can work. Or they might be able connect you with someone in your area that modifies bicycles for people with mobility issues.


How much of a difference do Toe Pedal Clips make in comparison to Platform Pedals?

I found toe clips to be better than platform pedals, but not by a huge amount.

Seriously, get clipless pedals. It doesn't matter how much traffic there is as it's so easy to get your foot in or out of the pedals. The advantages are huge.

The cycling shoes are so much more comfortable than street shoes
Your foot is so secure on the pedal - you can confidently apply as much force as you want, knowing that your foot will not slip off the pedal
You can get extra oomph up a hill by pulling with your back leg.

Once you get clipless pedals you'll never look back!


Just curious what DIY setups have worked for removing crown race from a steerer tube?

A method I've never loved but have used a time or two and seen others use a lot is an old disembodied pocket knife blade and a hammer. Carefully tap it in along the spine at multiple spots to wedge off the crown race. This method does work well, including on forks that offer zero overhang of the crown, but it has some risk of cosmetic damage in the best case, and on a carbon crown I'd worry it might be capable of doing more. You could mitigate that risk by using a thinner blade, probably.

I kind of hate the idea of using this approach on an all-carbon fork (as opposed to an aluminum crown), but the truth is that proper tools work on a pretty similar principle in these days of zero crown overhang being common, and themselves are not totally free of any risk of damage even if used carefully, so it may not be as stupid as it seems. On an aluminum crown you can do it all day as long as you don't care if it looks pristine.


First, not all full suspension bikes use bearing for all pivot points, and some bikes don't use them for any. They use bushings instead.

That said, assuming you have bearings at all points on your bike:

There are 2 types of bearings damage which require replacement in a suspension system.

The first, bearing play, means lateral movement inside the bearing cartridge itself. This occurs when the ball bearing wears deeply enough into the bearing race that there is space between the 2 races which is larger than the ball itself.

In a suspension system, this often presents as clicks or creaks in your suspension. It can be mimicked by loose pivot bolts, so the first check is to remove, grease, and re-torque all the bolts in your system. If the play persists, you may need to replace bearings.

The second, rough bearings, is often caused by extended use, or heavy impacts in the course of the use of your bike.

The ball bearings or races get physical chips or divots in their surface called pits, and thus no longer roll smoothly.

The presentation is often the same as with bearing play, clicks or creaks in the system.

The good news is that the diagnostic for both types of bearing issues can be done in one go.

Once you have pulled, greased and re-torqued the bolts in your system, disconnect the shock from you system, remove your rear wheel, and move the swing arm through its travel by hand. You should be able to feel any roughness in the bearings.

Repair in both cases requires replacing the bearings. This sometimes requires or at least strongly recommends tools specific to your brand or model of bike.


Mountain biking: lower-back pain in "attack position"

I'm don't think much of staments that any one position is “exactly the correct position”. Any position is wrong if you need to strain and stiffen yourself to keep it.
It's true that the “attack position” works well in a variety of riding situations, but there's no point keeping it all the time when there's not even something to attack in the trail! Especially for downhill, the more flexible&free you can move around the bike, the better. Do default to “attack” in doubt on technical bits, but then relax again.
Yes, occasionally switching what foot is forward also helps and is a good thing to practice, but many (most?) mountainbikers always coast with the strong foot forward, so this should really not be necessary.
Also, bike setup can make a lot of difference. Try raising the bars a bit, softer rear suspension (if you have) or plusher rear tyre. And clipping into the pedals has many small advantages, especially when it comes to riding more relaxed, because you won't need to spend effort just to keep the feet on the pedals.


Helmet strap loosens as I ride then the day after becomes too tight

Two One hypotheses:

The straps are getting wet with sweat and loosening, then constricting again when they dry. Nylon does in fact absorb water and stretch when it gets wet, so this is the more likely cause.

2. Exertion causes vasodilation. If you've had the sensation of your necktie getting tighter under stress, this is the cause. Your body is pumping more blood to your head and the veins are expanding.


Presta valve inner tube issue: area around the valve does not fill up

When you fill up an inner tube outside of a tire, the area near the valve will look a bit constricted because the rubber is reinforced in that area:

However, when you fill it inside the tire, don't worry - there's enough stretch in it so that it will expand to the right size and work properly.

The same goes for patches. If you fill the patched inner with air outside of a tire, the patches will deform the tube, but it'll still work just fine once in the tire.


Upgrading everything to Ultra R8000 except for crankset which is Shimano Sora

In short, yes but not well.

The distance between the chainrings in a Sora crankset is different than the Ultegra crankset. So if you have an Ultegra shifter and front mech, you may experience some issues (chain rub, delayed shifting etc).

So it will work, but not as well as it should.

An alternative is to get a 105 crankset, or other crankset of similar dimensions (like a Praxis Works for example). You could always set it all up with your Sora crankset and see how it goes. But be prepared to get another, more suitable crankset. Maybe post a different question that asks which cheaper cranksets will work with R8000.


Ghost shifting with a nearly fully rebuilt drivetrain

Check the derailleur hanger alignment. If the derailleur cage is not parallel to the wheel ghost shifts can happen.

I'd also check alignment of the rear triangle and dropouts.


Is it normal for a fixed gear bicycle's rear wheel to slip forward in its dropouts from time to time?

This can be a fairly common occurrence with a fixed wheel bike. It may depend on a few different things, ie what sort of nuts you are using, how tight they are, what style of dropouts, and what the dropouts are made of.
A different sort of nuts may help. eg something with serrated nuts or washers could grip better. Also you may be able to tighten the nuts more, maybe a bit higher than what Park recommend.
Probably the best option is to use chaintugs. These fit on the dropouts, and have some sort of screw to hold them in place. So this stops the axle from moving forward. Usually you only need one, on the drive-side dropout, though you can use one on each side if you want.
One example is the Surly Tuggnut.

(source: surlybikes.com)


Can I replace a Shimano FC-MT500 26/36 crankset with a Shimano Ultegra FC-R8000 36/46 set?

Unfortunately no, the Ultegra crankset is not compatible, nor is any other road Shimano crank designed for a Hollowtech II bottom bracket (assuming this is your bike).

The issue is that there are MTB and Road versions of Hollowtech BBs. MTB ones fit in 68 or 73mm shells, using 2 2.5mm spacers on 68mm ones. Road BBs only fit in 68mm shells. MTB BBs are therefore 5mm wider than road ones. Road crank axles are 5mm shorter than MTB cranks, and are only long enough for road BBs.

If you have a 68mm BB shell you could put a road BB in it and fit a road crank but the chainline would be way off.

You could look for larger aftermarket chainrings in the Shimano asymmetric 4-bolt pattern, but you have to deal with chainring clearance issues Andrew Henle described in his answer.


Riding position depends on different things, of which the bike is just one. The distance between the saddle and the handlebars combined with the the length of your body and your arms limits the options you've got.

But the kind of cycling you do is just as important. When riding around town, especially in crowded places and/or when not being in a hurry the best thing to do is to sit straight up. It allows you to make short turns, it's easier to stop, it's easier to look around you and allows you to talk to the person riding beside you. (With some practice you take you hands of the handlebars and still steer with just your balance and stand still on your bike without getting a foot on the ground). You need your saddle to be somewhat below your handlebars, but still at a height where you don't have to bend your knees to far. This basically is the way the Dutch cycle around town. It works when you treat cycling as an alternative to walking around instead of a sporting activity or a way to go fast. (Because, when moving around on your feet you're not running all the time either).

Judging from the image your bike seems suitable for that, the pedals seem to be slightly more forward then a road bike, which will push you a bit straighter up anyway.

If you want to go faster you can lean more forward, but depending on the length of your body that might get a bit cramped. If that's an issue you could but an armrest like this on the handlebars allowing you to lean further forward.


Chain link jams after reassembling the rivet

This often seems to happen.  Sometimes it helps to use the tool to push the rivet back out the other way a fraction of a mm.

If you are using a Shimano chain, then using the pins with a snap-off driver can help.


Based on a quick search on Google, I was able to find Portsmouth Campground, which looks to be pretty close to the trails. They also have yurts available, which might be nice as they aren't too expensive and you might even be able to fit your bike inside if you didn't have too many people.