New Shimano m615 rear caliper fails and stops biting the rotor after 30 seconds of extreme downhill

It's easy to determine that you're obviously losing your braking power due to heat generation. But hard to pin down exactly what's wrong without actually looking at your bike. There are a couple of things that could be going on, which could be a result of a mechanical issue, or an operational issue.

Mechanical Issue

First of all, your m615 brakes are only middle of the line, they aren't intended for extreme downhill (check out the Saint line), but even still, 30 seconds isn't a very long time before failure. There are a number of questions I would ask you in the shop;

Has this always been a problem, or is it something new?
How long have you been riding these brakes?
When was the last time you changed your pads?
When was the last time you had your system bled? and Did you use Shimano oil?

I would also inspect your bike, check what size rotors you're using and look for any obvious signs of oil leaks. I'd check the wear of your brake pads, and use a micrometer to check the wear on your rotors. I would look at the colour of your rotors, if they're blue then you've cooked them and they need to be replaced (Bluing steel makes it harder, harder steel means less friction–ergo–less stopping power). If nothing was visually obvious then I would bleed your brakes to check the condition of the oil, and make sure there isn't any air in the system.

Shimano Brakes use mineral oil, which is different than the DOT brake oil that would go in your Hayes brakes. Different oils have different boiling points, DOT oil is regulated (DOT 3, DOT 4, DOT 5.1-The higher numbers reaching higher boiling points) But Mineral oil is not regulated, which is why it's recommended to use the manufacturers oil. Some shops use bulk mineral oil made for other applications because it's cheaper to buy (Shimano oil is expensive), but it may not necessarily have a high enough boiling point. If your oil isn't pink, then it's either dead, or not from Shimano.

Opperational Issue

This is the part where I grill people about how they ride. Improper riding habits are a mechanics bread and butter, I've replaced more parts from riders causing damage to them than from parts wearing out due to normal use. One of the bluest pair of rotors I've ever seen came off of a bike whose rider was probably a good 250lbs and rode about 10km back down a trail–that was ALL downhill–riding his back brake the whole way. You have two brakes for a reason, and the FRONT brake is the one with all the stopping power. When riding extreme DH, your back brake is for steering, your front is the one that stops you. You need to use them together when you need a lot of braking.

I gave my big friend with the blue rotors a long lesson in proper braking, then installed a new 8' rotor on his rear wheel and a big 9' rotor on his front. He never had brake problems again. It's important to make sure you have a braking system that can handle you and what you ride, if you're  bigger guy, then you're going to need bigger brakes, if you like to ride fast and steep, then again, you're going to need bigger brakes.

If bleeding your brakes or swapping out brake parts is a bit beyond you, then you need to take your bike to your local shop, they'll be able to tell you exactly what's going on, and may recommend you upgrade your brakes or your rotors. The alternative is to slow it down and ride gentler grades.


As a parent who has been through this with two children and multiple bikes, I would definitely choose the dual sided pedal option (sometimes called "campus pedals"). This has the advantage of needing to only change the pedals once, and not having extraneous parts that can easily get lost.

I've personally tried the adapters and never found one I was particularly fond of. When dealing with a child's bike, I would want to avoid anything that could easily get lost.

The option to swap out the pedals would be my second choice. It's not hard to do. But it does have a couple drawbacks. You are again dealing with extra parts that can get lost. As well, it's easy to mix up the sides, or cross thread the pedals, and now you are dealing with replacing the crank arms. Finally, most 9 year olds lack the leverage to loosen a tight pedal, so you are going to have to be the one switching them whenever they want to change the ride.

I actually use campus pedals on my main commuting bike. That way if I ever decide that instead of riding the whole way home, I am going to take the train to the closest stop and just ride the last 2 miles, it's easy to do in street clothes with my normal shoes.


Possibly a THRODWN. The BMX brand was started in 2015.


What sites support Garmin Edge 200 .FIT format?

@freiheit answered above, but I highly recommend strava.com as the added component of segments and battling it out with my friends over a section of road whether or not we are riding at the same time, or even if we are, seeing how much time I took back (or gave up) on a hill is pretty cool.

With a paid membership they add additional ride analysis, such as HR and power. With your entered body weight and bicycle weight it will estimate your power and have found it to be a little off of my measured power, but it is always off by the same, so you can use it for trends (up or down) but wouldn't compare it to other cyclists too much.

I prefer it so much that I am now logging all my rides, runs, swims and other workouts, basically using it as my training log.

Another option (not a website though) is SportTracks from Zone Five Software, download this onto your computer and import your rides, your data on your computer. I've used their free version and have to manually upload/import my .FIT files. I think the newer version will read right off your device.


You need a bunch of things.

left hand shifter, or a left hand replacement brifter if your bike has integrated shifters
front derailleur mechanism with a band-on (aka bolt-on) clamp mechanism and diameter of the same size as your seat tube
new inner gear cable and cable housing for the front mech
a pair of cranks that have the same length, and same size pedal mount hole as your existing pedals
the right hand crank should have chainrings sized to suit your need.  Since it takes a 50T now, smaller toothcounts should fit fine. Cranks should have the same BB interface as your current BB axle (probably square taper but others are possible)

Depending on the details you may also need

new bottom bracket axle with more length
bolt-on frame cable stop for the seatpost.  May need to be angled, OR
an "under-BB" cable guide.  Generally it is a piece of plastic, and is screwed into a hole in your BB
bolt on downtube cablestops or holders (if cable zip-ties aren't to your taste)
new grips/bartape.

Sourcing parts

If you have to buy all this new, it may be cheaper to buy another bike.

If you have access to a donor bike, something that has been crash damaged could be good.

Or start exploring your local bike cooperative or ebay/CL/gumtree etc.


Dynamic brakes are used on electric trains (sometime true regenerative brakes are not used because dynamic brakes are far simpler). I think they may also be used on trucks to regulate speed on long downhill roads.
You’d need a generator built into a wheel, like a dynamo hub, but somewhat larger to provide greater braking force. Power is dissipated in large resistors with cooling fins much like the cooler on an PC CPU. Depending on how sophisticated you want to be you could include a controller circuit to vary the braking force.
The issue is that all this adds significant mass to the bicycle, and the generator will create a non-zero resistance even when off (unless you provide a clutch to disengage it). Given that by definition you need to ride this bike up a hill in order to descend it, is the trade off worth it?


What are some other places to buy MTB frames online?

In the US http://www.performancebike.com and http://www.nashbar.com are two big online bike outfitters.  I don't know that either sells bare frames, but they do sell a wide variety of stuff.

And of course a number of custom/low volume bike builders sell bare frames.

Here is a pretty good list of bike & frame manufacturers.


Is there a difference between big chainring and big sprocket, and small chainring and small sprocket?

Depends - you are cross chaining when in the big/big and small/small combinations.  See this question:

How bad is cross chaining?

Also, theres a question of ratios, but this is more theoretical.

Assuming your rear cassette ranges from a 12 to a 28 tooth, and the front chainring is 52 and 42, then Sheldon says these are your Gain Ratios.

 Gear chart using Gain Ratios
 For 700 X 28 / 28-622 tire with 12-13-14-16-18-21-24-28 8-speed cassette

      52        42    23.8 %
 12   8.7       7.0   8.3 %
 13   8.0       6.5   7.7 %
 14   7.4       6.0   14.3 %
 16   6.5       5.3   12.5 %
 18   5.8       4.7   16.7 %
 21   5.0       4.0   14.3 %
 24   4.3       3.5   16.7 %
 28   3.7       3.0

so expressed another way, here are your overlaps, where 1 is the biggest cog and 8 is the smallest.  (42/13 is almost the same as 52/16)

 52       1   2     3   4 5   6 7 8
 42   1 2   3   4 5   6   7 8

So if your comfortable speed for a road is in the middle of the range for 42 tooth chainring, its at the bottom of the range for the 52 tooth.

To say that another way, the 42 tooth chainring has more ratios closer together in one are, at the cost of having no ratios elsewhere in the range.

So on our hypothetical 8 speed there are two gears almost identical, 42/13 and 52/16.  Why choose one over the other?

Cross Chaining - the smaller chainring will be "happier" with the cassette at 1-5 and the larger chainring will go better with 3-8.  There is overlap.
What's coming up - if you know theres a climb, a descent, or an obstacle/stop then you might choose to be in 42 for the climb, or in 52 for the descent.  For a stop, you'll probably change gear, 42/13 would be a bit hard to pull away from a dead stop.

If everything else was the same, I'd choose the bigger pair over the smaller.  More teeth in contact with the chain means slower wear.

Play about with Sheldon's calculator at http://www.sheldonbrown.com/gears/


Are bicycles with wide tires bad for road racing?

Wide tyres are designed to be pumped to a relatively low pressure so that they bend around objects they roll over, to give grip and a smoother ride. They also often have lots of bumps and lumps on them: again, these dig into the ground and bend around things for more grip. However, bending and deforming all this rubber hundreds of times a minute takes a lot of energy. The only source of energy on a bike is you, so this means that a lot of your energy is going into the tyres, rather than driving the bike forwards. Sometimes, you hear a mountain bike with really knobbly tyres being ridden on the road and it sounds like a swarm of bees: that's a lot of wasted energy.

Suspension (front and rear) is, by design, flexible. This means that, when you press on the pedals, some of your energy goes into driving the bike forwards, but some of your energy goes into flexing the suspension.

Roads are relatively smooth, which means that fat tyres and suspension aren't giving you any advantages. But they're still there, using your muscle power for useless things. They're also heavy, which makes it harder to accelerate your bike and harder to go up hills. These are significant disadvantages to using this kind of bike on the road. Another disadvantage of mountain bikes is that they often have very low gearing, which means you can't go very fast, even spinning your pedals as fast as you can.

Some bikes with suspension have a control that lets you stop the suspension moving. That would be a good thing to use when riding on the road, but you'll still be carrying around all that excess weight and your squishy, fat tyres.

And, in fact, you might not be allowed to ride a road race on your particular mountain bike. The international regulations of the UCI require something fairly close to a traditional diamond frame. The intent was to exclude some of the extreme aerodynamic designs that people were experimenting with, but a mountain bike with rear suspension would also probably be forbidden under these rules. Although any race you'd be likely to enter wouldn't be run by the UCI, local cycling federations usually use rules very similar to the international ones, so that the rules don't suddenly change when people turn pro.


Can I leave a suspension fork upside down?

You will not damage a suspension fork by hanging it upside down. Although the fork is air sprung it also uses oil for dampening in one of the legs. Oil may leak if your seals are degraded. The seals in suspension forks are made to ensure they don't react with the suspension oil. The oil will actually help lubricate the seals.

This is the same for coil (spring based) forks.

Once you refit your fork it will take time to settle back to its original state.


How to gain confidence with new "big" bike?

Not to be trite, but: Get out there and ride!

I just tried out a 29 Plus mountain bike a few months ago, first time on a MTB in years. Felt really weird and disorienting at first, so I just rode on smooth gravel pathways for a while. Once I started feeling a bit more confident in it, I started going out of my way to run over small rocks, twigs, branches, etc., to get a feel for how the bike responds. Quickly built up to "cinder-block" size rocks (breeze-blocks if you're in the UK). It was really fun "relearning" - it's the first time in a long I've felt like a little kid on a bike.

There's no rush, nobody's going to appear out of the bushes to laugh at you when you decide to go around a larger obstacle that you're not yet confident rolling over.

It's not clear from your post what your level of experience is, but if you're feeling really nervous and cautious, just ride on a pavement for a few days. Try rolling off curbs (check for cars first!). Try rolling along on some grass.

Have fun with it!


120 KG is 265 lbs. You might want to contact the manufacturer to get an exact number on the recommended maximum rider weight. Other bikes by high end manufacturers usually are around 250-300 lbs. Usually aluminum/alloy frames are around 300 lbs while carbon frames are around 250 lbs. This isn't because carbon is weaker, but rather because carbon bikes are designed with a different kind of rider in mind.  Double check with the manufacturer, but you are most likely fine. You may have problems with bent spokes if you are rough on the bike, but the frame should be fine.


How do downhill riders cope with this?

With a front fender or with a mud guard such as this.
With goggles which use disposable tear off lenses or the ones with a reel of fresh len material which is pulled via a string or via bluetooth or something.

  Does the full-face helmet protect the mask in some way?

Probably not.

  Do they apply anti-water coating on the mask?

No

  Do they install some hardy front fender?

In really muddy conditions it's almost mandatory.

  Or do they just live with it?

Nobody likes mud in their eyes or mouth.


What is the axle thickness of the Kent Road Tech 700c bike?

I can't find "roadtech" on www.kent.bike so there's no real way to look it up in the catalog.  I could only find some pictures on mass-market websites, and from the look of it, you've already got regular solid axles with hex nuts.

If I had to guess, I'd say 9mm on the front and 10mm on the rear, but that's totally a guess.

Your best bet is to measure.  Take one front nut and one rear nut to a hardware store and see what size bolt fits.  9mm and 10mm are the most likely, but 12mm and 3/8" are also possible.

The other thing you could do is just lock the wheels to the bike and park in a public place.  Those locking nuts are really expensive.


My rear wheel is wobbling much after around 3 months of use. Is there any fix that i could do it or should i replace the wheel?

If the rim is moving side-to-side when you ride your wheel is out of true and needs truing (i.e. the spoke tension has to be adjusted). It’s especially noticeable with rim brakes because the rim will start to rub on the brake pads during some parts of its rotation.
If only the tire is wobbling: Some wobble can be normal, if it’s worse the tire is probably not well seated in the rim. You can try inflating it to maximum pressure (or even slightly more) and see if it “pops” into the correct position. Release air until you’ve reached your desired riding pressure afterwards.
If the cassette or sprocket looks like it’s wobbling: Sometimes it just looks that way, but make sure it’s tightened (cassettes need up to 40Nm of torque, which is quite a lot) correctly.


Why do some bicycles have much bigger wheels than most motorcycles?

Gearing is a factor, although by no means the only factor. Common wheel sizes allow for conveniently sized sprockets, both front and rear. The bike industry has always been driven by what racers need, and pro cyclists can reach 100 kph+ on a downhill. The higher a gear you can be in, the less likely you are to "spin out" and no longer be able to pedal effectively. The larger the wheel, the further you move in one revolution. The internal combustion engine can achieve 1000s of RPM, an order of magnitude above what human legs can sustain, which at least in a lab setting start to lose efficiency by around 100 rpm (http://link.springer.com/article/10.1007%2Fs00421-004-1175-5), and above a certain point (which is perhaps the topic of it's own question) are totally unable to keep up with the pedals, let alone apply meaningful power. That's why penny-farthing style bicycles had such big wheels, since the cranks were attached directly to the wheel, the only way to go faster was to get a bigger wheel.

Chain drive and gearing fixed this issue, allowing for smaller and lighter wheels and a top-tube below crotch height. But there's practical limits to how how large a chainring and how small a rear sprocket you can use. Too large a chainring will start to flex (this was more of an issue before modern materials), and currently the smallest rear sprocket on a standard cassette is 11 teeth, on old 5-speed freewheels it was usually a 14 tooth. A 700c wheel with a 25mm tire can reach ~73kph @ a cadence of 120 rpm with a standard racing 53 tooth chainring and an 11 rear sprocket. To get the same gearing, a 20" BMX wheel would need a 75 tooth chainring that would be roughly 12" in diameter, and a 16 inch folding bicycle wheel would need an 83 tooth, 14" diameter chainring.  As well as flexing, they would need to ensure the bottom bracket was high enough to keep the chainring from brushing the ground when cornering or on rough terrain (curbs, potholes, roots, and the like).

And some bikes do actually have very small wheels, like folding bikes. But their top speed is limited. Some rear cassettes with 9 tooth smallest sprockets have been made (See http://www.sheldonbrown.com/capreo.html), but engineering concerns make them expensive and prone to wear. And even then, standard 26" and 28" (aka 700C aka 29") wheel sizes were set 100+ years ago, and folding bikes tend to look "goofy" to people compared to more conventional bikes. And the UCI likes mandating that modern racing bikes have roughly the same form as they did in the 70s, including a diamond frame and wheels between 55 and 70 cm.

Another standard reason given why mountain bikers should favor 29" wheels over 26" inch wheels is that they "roll better". The larger diameter means that it gets stuck less in small ruts and holes, rolling over it rather than down into it. The larger tires also mean a larger volume of air, and thus less need for suspension. Motorcycles are already much heavier (with the requisite power to move much more weight), so beefing up the suspension is less of a problem. The 26" vs 29" (vs 27.5") question is far from settled, but the trend is moving towards bigger wheels, not smaller ones.


From these three, which one you have?

Case ①:

Schrader valve

Check if the inner part (valve) is properly installed (tight enough). If is and still loose air — you need to change the valve or the inner tube, the problem is with one of them.

Case ②:

Presta valve

You need to unlock the valve before pumping, or you will pump air only into you pumps' hose. After pumping don't forget to lock the valve back.

Case ③:

Woods (Dunlop) valve

Very old system. Check inner parts (steel needle and rubber tube) for damages, rubber tube can degrade flexibility with years → air loss.


Where possible, replace with stainless fasteners. Things like water bottle bracket bolts are readily available in stainless at a good hardware store.

But most fasteners on a good quality bike are stainless to begin with, so it may be that you're not seeing "rust" per se but rather a sort of corrosion that can form on stainless.


How can I upgrade to a better gear range?

No, your derailleur won't work with 9 speed casette. Well, it could work on 8 sprockets of the 9, but that won't help you.

You certainly can buy a new 8 speed casette from the Claris line (or MTB) but you cannot take just any, you cannot go over your derailleur capacity and over the largest sprocket size supported so you are out of luck for the modern 32T casettes. Unless you find a good deal on a more recent 8-speed RD (like the new Claris 11T-32T, however, it is also sold as  11-28T, 12-25T, 13-26. The 28T is one tooth over your RD but might still work.).

Changing one chainring should work, check it is a compatible one. That would be cost-effective. If you have the Sora 3300 FD, it has the capacity of 15T, so with 52 big ring you can go to a 37 small ring.

Otherwise, you could always buy a whole new crankset, for example, a compact one (50/34), those are the most common and certainly would bring you a better gear range. But I am not sure about the 16T difference with your front derailleur. There are two versions of RD3300, one is SS and one is S
GS. One supports the front chainrings difference of 14T, the other 22T. If you have the GS (total capacity 37T), you are good to go, but with SS (total capacity of 29T) the shifting might have some problems.

Again, better to take an 8-speed one from the Claris range, or an older 8-speed Sora. But, buying a new crankset will be the least cost-effective. Unless you find a good deal on something older (but better unused).

This kind of crankset would be a good candidate https://sprockets.uk.com/shimano-rs200-8-speed-compact-chainset-black-170mm-34-50t/ (I mean RS200, this specific 170 mm might be too short for you). But for the SS version the difference is officially too big.


Can I mix these SRAM Apex components with Shimano/Ofmega components on my bike temporarily?

Proof's in the pudding, but generally you should be fine with this setup as long as the frame's OLD is large enough to take your new rear wheel hub.

The trick is to keep the front mech and shifter compatible with each other, and keep the rear mech and shifter and cassette compatible.

One interaction can be that the narrower width of the 10 speed chain takes longer to move chainrings at the front because the front mech's cage is for a wider chain.  For a beater bike you might squash the cage horizontally a bit, or learn to live with it.

Also the RSX shifter on the left of your bars will be mostly grey, and the new one on the right will be much more modern-looking.  A workaround here is to use a downtube shifter on the left for the front mech, and leave the left brifter as only a brake.  This was a thing in the 90s, noticeably some yellow texan.


Apart from going the high-tech route of a front suspension with lock-out, you can also try to get wider tires. The slow-down of wide tires is not that big, but they naturally even out high-frequency bumps. The wider the tire, the smoother your ride gets on the rough roads. Maybe, that's all you need.


Can I use a Suntour Cyclone GT Rear Derailleur for a 10 speed Campagnolo cassette?

Campagnolo 10 speed cassette is only 0.6mm wider end-to-end than their 9-speed cassette, so as long as the 9-speed setup still has that much adjustment in the limit screws you should be fine on that count.

The jockey wheels only care about the inside width of the chain which is 3/32" on pretty-much all derailleur gear systems that have ever existed, so you won't need to change them for that reason.

I would try it, if it doesn't work you can always fall back to your 9-speed plan.


Should I clean the grease off the gears?

I clean my gearing and whole drive train every few months. I ride about 250km a week so it's not a time frame requirement but a use thing.

I would suggest that every few thousand km or each year you should take apart your whole drive train and get it entirely clean. Replace your chain but keep the old one just in case the new one skips. I replace my chain with each cleaning so that the gearing doesn't wear to fit the chain and thus cause skipping. Well worth the price of a few extra chains vs the cost of a replacement cassette.

My goal for each cleaning is that all parts should be back to their original colour. The older they are the less you can acutally do that as they scratch up but I'm sure you get the idea.


I had problems with cramps in my legs after about an hour of exercise. A friend of mine that is a physical therapist said that if you sweat a lot this can cause loss of potassium, calcium, and magnesium. These minerals are used to signal the muscles to flex and relax. I started eating vitamins with these minerals in them. Since then my problems are gone.

Stretching and a good warm up is also important to prevent cramps.


Should I change both tires when I need to change one?

No.

In a car, the weight distribution is relatively even and you tend to get a relatively even wear, so that if 2 or 3 tires are obviously ready for replacement, you probably just can't tell that the others are ready. I suspect that also having 1 tire with a different amount of tread wear than the other tires on a car will lead to an unbalanced configuration that causes tires to wear out faster. (especially a left-right imbalance)

With a bicycle, the rear tire gets more weight on it than the front and will generally wear out more quickly.  By as much as 3:1. Because of this, and other reasons, some people will even use a totally different tire on front than on the back.  (could have the narrower tire on the front or on the back, depending on what you want to achieve)  On a bicycle, it's perfectly fine if one tire has worn down to being effectively smaller than the other.  You will never notice if the bike is "leaning" a millimeter or two forward or back.

The rear also tends to pick up more thorns/nails/screws/glass than the front, so there's also that reason the rear may need to be replaced sooner. The usual theory I've heard is that the front tire knocks the sharp things into a point up configuration in time for the rear tire to catch them, but I strongly suspect that it's more about weight distribution: the tire with more weight has a bigger contact patch and will push down harder on something it rolls over.

Overuse of the rear brake instead of learning to use the front brake properly can cause the rear to wear out even quicker.

You also don't want to rotate your tires between front and back.  That's something suggested with some cars, I think because you tend to wear the front differently than the back and can get a longer life that way.

However, if you're using the same type of tires on the front and the back, and it's the rear tire that's being replaced, you probably want to move the front to the back, and put the new tire on the front.

You always want your best tire on the front.  A blowout in the rear is scary and inconvenient, but a blowout on the front is very likely to lead to a crash.  You also need the traction on the front for stopping much more than you need traction on the rear for acceleration. (and because your weight shifts forward as you stop, you just can't get very much traction on the rear for stopping)

Reference: http://www.sheldonbrown.com/tire-rotation.html


Listening to audio without obstructing ears

I'm assuming you want those more to be able to hear traffic, less because how unobstructed ears look. I use a pair of cheap sony ear plugs. They're the kind of plugs that don't go all the way in the ear, but are only small round bulbs that sit at the front. Thus they still allow me to hear everything around me perfectly.


Zero-gap stem (FSA Afterburner) inverted installation

I'd follow your option 2. The labels on the faceplate and body of the stem appear in both orientations, implying FSA designed it and labeled it for use either way. Given that, they must have intentionally only put the "no gap" label in one place for use in both orientations.
Grease all the bolts, unless instructions say not to, or they are already lubricated/protected by another method like threadlocker. Aside from lubrication, grease or threadlocker creates a physical barrier between the threaded items, reducing corrosion.
Regarding threadlockers, there are various types:

Added liquid chemical threadlocker which cures to a solid between opposing threads, in theory preventing movement and loosening. Oil/grease can interfere with the curing process. When removing and reusing the fastener, the old threadlocker must be cleaned off and fresh threadlocker applied.
Preapplied malleable solid mechanical threadlocker. This works by remaining malleable and dampening vibrations, thus preventing movement and loosening. There is no curing process, so it should be at least somewhat compatible with oil/grease. When removing and reusing the fastener, the existing threadlocker is reusable as long as enough remains in place.
Preapplied "dry" chemical threadlocker. This is basically just liquid chemical threadlocker encapsulated in tiny beads which break open when the fastener is tightened. Oil/grease may interfere with its curing process, although Henkel/Loctite says its "dry" threadlockes are "Solvent/chemical resistant - all oils (motor, ATF), water, glycol, petrol, diesel". Like liquid threadlocker, when reusing the fastener, this needs to be cleaned off and fresh threadlocker applied.

Here's what I do:
a) follow the instructions for the part if available.
b) always use grease/antiseize/threadlocker of some type on threaded fasteners (unless instructions say differently).
c) if I feel the amount of pre-applied threadlocker is not enough to reach the full length of threaded contact, I may add a small amount of grease or threadlocker to the threads away from the pre-applied section. Just as with beer, one can assemble quite a collection of different types of threadlockers :)
Some references:
https://www.assemblymag.com/articles/85609-do-your-fasteners-need-a-preapplied-thread-locker
https://www.fastenal.com/content/documents/2014/08/Loctite-Threadlocking.pdf
https://www.henkel-adhesives.com/us/en/products/industrial-adhesives/anaerobic-adhesives/pre-applied-adhesives-sealants.html


Sunglasses anti-fog solutions safe for cycling

The answer is "they are probably safe" and "they don't work for spit".

Skiers have exactly this same problem with ski goggles and what I have learned in 50 years of skiing is that if the goggle has an built in anti-fog coating, cleaning it with anything but a mild soap will ruin what minimal anti fog coating
it has. Sunglasses generally don't have much in the way of anti fog coating. I tried everything I could find and it was all a huge waste of money.

What I have found that has largely fixed the problem for me in skiing is two things.

Wear a helmet. ( this probably doesn't apply to bike helmets, but ski helmets do a lot to keep the moist warm air from your head away from the goggles. )
Change your jacket.

When I switched from skiing in a Goretex jacket to a jacket that actually breathes (soft shell) 99% of the goggle fogging problem disappeared. Anything that is a vapor barrier just funnels all the warm moist air from your body directly up into your face. The only WB fabric I've found that comes anywhere close to venting well enough to use with aerobic sports is eVent.

Applying this to your situation, you need a face mask that breathes better. Either that or one that some how seals to your face at the top. There is no magic goop that will prevent fogging, the only solution is to keep the moist air away from the glasses.

After you give up attempting to keep your current sunglasses from fogging, you might try a pair of these.

http://www.xcskistore.com/casco-nordic-spirit-ii-white-nordic-ski-eyewear.html

They are very expensive, wierd looking, but they are by far and away the most fog resistant eyewear available. I've used them biking and for all kinds of skiing and  they just don't fog up ever.


Can I convert freewheel hub to use cassette?

No, it is not possible. You need to replace the entire hub, and the easiest way to do that is to replace the entire wheel.


Did my bike shop con me into replacing both sets of Trek 7500 Hybrid disc rotors?

There are at least two questions here: 1) did the rotors need replacing; and, 2) was £70 a reasonable price for that repair.

1) Did the rotors need replacing: Unless you have photos, it's difficult for us on the intertubes to ascertain. Blue-ing is indicative of very high temperatures - likely produced when someone went down a very long, steep incline while keeping the brakes half-depressed. This produces a lot of heat and can damage not only the rotors but the pads and brake housing itself. The heat warps the rotors and also weakens them.

As for the explanation that "both sets of disks were badly 'burned' through excessive braking with damaged pads" - it would be the excessive heat produced by braking over a long/hard distance that damaged both the pads and the rotors.

So the tl;dr here is that blued rotors might not have needed replacement if you weren't going to ride them aggressively and they might have been able to have been straightened back into shape. But the bluing weakens them for sure (even if just a bit), and the shop may have felt for liability reasons that it was best to recommend replacement. After all, if the rotors did the extremely unlikely thing by shattering right as you headed towards a lorry truck, you (or your lovely widow/er) would have sued them out of existence. Better to be safe (and make a sale) than be sorry.

1a) Maybe the discs were just scoured? It is possible that the discs were just scoured - especially as we don't have photos. Damaged or badly worn pads could have scoured the rotors - as well as a general lack of cleaning and maintenance. That would explain the black streaks you saw. You should have also been able to feel the scouring with your fingernail.  In fact, given that your bike is a hybrid and not likely to have done aggressive downhilling, scouring is a more likely explanation of what happened even though the words "burned" and "blue" that you used are indicative of blue-ing.

If your rotors were scoured, they'd still need replacing if the noise bothered you since resurfacing bicycle disc rotors isn't worth the money. Even if you decided to put up with the noise, you'd have to replace them when the pads ended their already shortened life as you shouldn't put new pads on a scoured rotor as the new pads will pick up the scouring, shortening their life and scouring the next rotor when/if you ever replace it.

2) Was £70 (approx USD$85) a reasonable price for replacement? We don't do valuations here, but the base price for a pair of the rotors would be around US$25-50 in 2017 dollars. Bike shop labor is around $70/hr here (and I should note that 'labor' also includes the rent for the shop, purchasing and depreciation of tools and equipment, training, utilities, etc.) and an hour of labor for installing the rotors, truing them, and adjusting the brakes is reasonable.  So, I don't think you were charged an excessive amount.

p.s. As noted above, I do hope they replaced the pads at the same time as replacing the rotors. This is standard for  both scoured and blued rotors and if they replaced the pads (another US$15-30 cost) then £70 was a really reasonable price.

pps. Scouring is indicative of a bike that wasn't maintained properly, blueing of a bike that was ridden aggressively. In either case, you should perhaps ask the bike shop to do a full inspection to make sure there aren't other hidden treasures.


What hydration system should I use for multiple activities?

If you're looking to go minimal footprint, with no storage, why not go no bag? These definitely have downsides, but they fit under anything, with any type of clothing, or sport.

Camelbak VeloBak Hydration Jersey

or

Camelbak Racebak Hydration Vest

Downsides include water which must be cooled, or will heat to body temp.

Check out the linked reviews.


I'll answer you comment on contacts, as I think you should investigate it.

I had the same dilemma a year ago. After wearing glasses for a couple of years for close up stuff, I was getting to the point I needed glasses while out on the trail. I looked around at options and decided to go down the contacts path. I now wear contacts in weekends and while riding, and have progressive lens glasses for work (computer based) that are suitable (although not ideal) for driving and distance. The glasses offer much better performance when its not raining, muddy etc, but when outdoors (biking, fishing, skiing etc) in all weather, contacts win hands down.

I suggest you discuss contacts this with your optician. There are a vast range out there, from one time use that you take out an throw away to monthly lens than can be left in for a week. Your optician will discuss the in and outs of different types and what suits you, and try various combinations till you get one that works. He will teach you to put them in and take them out - all the stuff that is "creepy" is dealt with - You get shown how to do it properly (and safely), and will be taught how to do it. Although not for everyone, I found it easy to learn to do.

I know you said cost is not an issue - that is good. Contacts are not cheap - initial fitting costs (where they also teach you how to look after your eyes and the lenses) - and cost of the contacts and cleaners mean glasses work out much cheaper.

You may also want to discuss lazer surgery with your optician.


The Code de la Route also states the following:

  En marche normale, tout conducteur doit maintenir son véhicule près du
  bord droit de la chaussée, autant que le lui permet l'état ou le
  profil de celle-ci.

Which means:

  In a regular situation, any driver must keep his vehicle close to the right side of the road as much as the state of the road allows it.

This part does not specify the nature of the vehicle so bicycles are impacted.

The "as much as the state of the road allows it" is a freedom breech that allows you to add good sense to this law:

ride on the right, but not too close as to be within reach of an opening door of a parked car!
ride on the right, but if the road is narrow enough that you consider overtaking by a car unsafe, prevent it from happening a ride closer to the centre!
ride on the right but if the side of the road is covered by debris, move closer to the centre!

True it might piss the drivers off but ensure your own safety first.

The police is not that picky with cyclists and when they're riding on the right half of the right lane, everyone is happy I would think.


Do 16g CO2 cartridges have a shelf life?

They last pretty much forever provided they haven't been damaged (e.g. punctured or rusted or something), so go ahead and use them.

If you really want to check them, you can buy a few new ones and weigh them on a scale (and compare the weights of the old cartridges to the new ones). If they're significantly lighter, they've leaked and throw them out. Else, go ahead and use them. But a few years (say less than a decade) is pretty much nothing in terms of having issues with the cartridges leaking.


In the automotive industry, "aftermarket" refers to, from Wikipedia, all the secondary market for all vehicle parts and accessories, after the original sale, including replacement parts and accessories, whether made by the OEM or not. I don't frequently hear this term used in the bicycle industry, but it does apply.
Licensed copies
In this particular case, it's worth discussing patents. To my current knowledge, Shimano's SPD-SL pedals are still under patent. I see on Google that Exustar offers an aftermarket version of the SPD-SL cleat, although it has 4.5 degrees of float (vs 6 degrees for Shimano's yellow cleats, likely not a limiting factor for most riders). I believe this is a licensed version of the SPD-SL cleat. I have no personal experience with it, and I'm not sure how these licensed versions have been sold.
Exustar have made either licensed or slightly variant versions of Look cleats for some time. Cyclingtips' review of road pedal systems in general argued that Exustar's Look cleats were better in some ways than the stock ones in some ways. Clearly, Exustar know how to make a decent cleat in general. I suppose you could also look through the Amazon reviews for their SPD-SL equivalent cleat. In general, licensed copies should be OK. I would expect them to be equal to or worse than the original product or OEM version.
In cycling, I can't really think of a licensed copy of a product that's superior to the original. In some cases, rim brake pads come close: Kool Stops are noticeably superior to many stock Shimano pads, especially the low end ones. At the high end, I've heard it argued that the Swiss Stop BXP is superior to the stock Ultegra or Dura Ace pads. These pads use the dimensions of Shimano's brake pad holders, but I would not say these are really licensed copies (the pad compounds are different).
Xpedo and Exustar may make licensed versions of the Look Keo pedals and cleats, and these products may vary slightly from Look's design. It seems like they may not officially call their systems inter-compatible with the original Look Keo pedals or cleats. The Favero Assioma power meter pedal is built on Xpedo pedal bodies and cleats, and a different article describes those cleats as a Look variant. The same is true of the Powertap power pedals. Some users report that original Look Keo cleats fit the power pedals, but the fit may degrade over time. Garmin's Vector power pedals (the second link) appear to come with Look Keo cleats, and if so, then I would assume Garmin licensed the Keo design from Look. I'm not clear on the licensing status for Xpedo and Exustar, but given the designs appear very close, I would assume those firms had to pay licensing fees. John Weirath, a bike fitter, documented on his Youtube channel that the variant/licensed Look cleats may have some dimensional differences versus the original items. In that video, the difference was enough to require a different cleat position.
Un-Licensed copies, i.e. counterfeits
Dishearteningly, there may also be counterfeit SPD-SL cleats in circulation. One post on the Paceline forum, this blog post, and at least one person in this thread on the Bikeradar forum reported bad experiences with cleats that were suspected counterfeits (i.e. advertisement implied that they were Shimano cleats or didn't clarify that they were not made by Shimano). Complaints related to durability and materials quality. However, at least one person on the Bikeradar thread did report satisfactory experience.
In general, if you are buying components that you know to be knock-offs, especially illegal knockoffs, of a genuine product, I would assume that the materials may be poorer quality. This could mean that the plastic is less durable and may break or wear faster, or that the rubber bumpers may not adhere as well as the stock cleats. Also, the tolerances could be poorer, i.e. you may get a set of cleats that fit too loosely or too tightly in the pedals (i.e. the variance in the physical dimensions is higher than the stock cleats). Naturally, it's not a given that non-OEM parts in general will have substantively poorer quality and function than OEM parts. It's just that it's more likely with parts that are counterfeit.
Also, apparently you now need to be aware that Amazon and eBay may have counterfeit SPD-SL cleats, as well as other counterfeit items. I hadn't really known about people selling counterfeit SPD-SL cleats until the Paceline post. I think that knockoff may be a synonym. This refers to something that's just a direct copy, with no regard for legality.
I recall that eBay had a problem with fake Oakley sunglasses years ago, when I was more credulous (and yes, I got scammed). I ordered a set of CPAP filters on Amazon. They weren't OEM, and it was clear that they fit a bit looser than OEM filters. My opinion is that with a relatively low-cost item like a replacement cleat, I am not likely to bother with third party options unless I know the third party produces good quality. This would actually include Exustar's cleats, so I may try them next. Items not licensed by the manufacturer are out for me.
Terminology - more on knockoff vs. counterfeit
Above, I refer to suspected counterfeit Shimano cleats because I believe that many sellers are passing off their products as Shimano, and I don't believe they have the legal right to do so. It's generally possible to produce a knockoff product without violating the law. If Shimano's SPD-SL system is still under patent, I assume the patent covers the physical dimensions of the cleats, so it's probably impossible to legally make knockoffs that actually work.
Shimano did, however, let the patent on their SPD mountain bike pedals and cleats expire in early 2019. SRM produced a pair of power meter pedals, reviewed by DC Rainmaker, that are compatible with SPD cleats. I don't think people would instinctively call this a knock-off product - this is a completely new pedal design, and Shimano don't even offer a power meter pedal. In any case, Xpedo either produced SPD-compatible MTB pedals under license, or else they just started producing them in 2019.
Legal knockoff products do occur in cycling. One example of legally copying a product is the Rock Brothers version of the Spurcycle bell. Spurcycle failed to patent their bell, so Rock Brothers was able to legally copy the design - although, as I mentioned above, their version had noticeably worse performance due to poorer materials and construction. Spurcycle is a small company, and they simply did not know about the importance of patenting. I'd assume Shimano didn't forget to patent the SPD-SL system, or to renew the patent if they were able.
Alternatively, in 2018, DC Rainmaker reviewed the Magene Gravat 2 smart trainer. He has extensively reviewed smart trainers, and the Gravat appeared to directly copy the physical dimensions of Wahoo's Kickr. He described it as "a bit of a copy-cat trainer." In this case, though, there is also the internal engineering of the trainer (which has a flywheel, a drive belt, and various other mechanisms), and there's also engineering the software to drive the trainer. The trainer as a system may not be close enough to Wahoo's for them to raise legal objections, or it may be impossible to fully patent every aspect of the trainer (IANAL). Also, Magene's color scheme is clearly different from Wahoo's, so there at least should not be any confusing Magene's product as a Wahoo.
Less closely, Silca recently released a compact saddle bag called the Mattone. Some commenters on the Bikerumor article I linked accused Silca of ripping off the Velocolour Rocket Pocket. IANAL, and I don't even know if Velocolour applied for a patent here, but the Silca product may be different enough to not be considered a copy - for instance, the attachment mechanisms are totally different. In the fashion industry, brands rip each other off frequently. For interested parties, here is a Vox article discussing the existence of the phenomenon, and the public policy case both for and against stronger copyright laws.


Garden of stones, that are similar to watermelons

On the type of rockgarden described, you can:

Reduce the slippage tendency by loosening your pressure on front brake. Let's put it this way: the stone surface provides you with little friction. In some circumstances, the friction is just enough to keep the tire rolling in line. Add the friction needed for braking and you overpass the available friction. The tire then will slide to wherever the sum of all other forces lead it.
You can predict where the tire will go when it slips. It will usually go to the gap between two rocks. Thus it is useful to pick a line where you follow the natural trace given by those gaps.
Ignore slippage. This is indeed is easier said than done, it sounds just weird, I know. The point is, if you pick a good line, specially a straight one, the inertia of your body mass is bigger than the one from your bike. This means that your body tends to go in a straight line, so even if your bike slips a few centimeters below you, it will not be enough to immediately tip you off the bike. You will have a fraction of time to react and return to the balance point. For this to work, your bod must be traveling in the direction of the line you have selected.

Finally, the general idea is to feel like you "float" over the rock garden, get used to the feel of the bike sweeping a couple of inches below you while keeping a good, firm but not stiff grip on the handlebars.

If you don't feel comfortable at certain speed, reduce it, and practice. Have patience. Sooner or later your speed will grow and you will master these sections. Also, with practice, your line selection abilities will improve, you will do it faster and find ways of sticking your front wheel in strategic points where it wont slip and those points will serve you to improve control, switch lines or change course. Remember: practice and patience.

On a side note: Did you ever as a kid played running and suddenly stiffening your feet so you slid on the floor for a couple of yards? You weren't afraid of such slippage right? Why? You already knew how to predict it, you actually enjoyed it, so relax and enjoy your gardens!


How does the frame split on the 2016 Novara Gotham belt-drive bike work?

I edited a photo of the relevant part of the bike into the question, but then decided to answer it. I can't find a photo showing any more detail than that, sorry.

The two weld bumps on the right hand seatstay will be where the the frame joiner has been put in, and resumably there's a bolt or two in there, but I can't find out, sorry. OTOH, it will almost certainly be easier to open that up than to find a replacement belt, so I wouldn't worry about it. It will definitely not require welding to do that, though.

This search for "belt drive frame joiner" produces a lot of hits, including an image that looks as though it could be the device used in that bike.

Image from road bike forums where there is a thread discussing how that device was installed in a frame. If it was turned so the bolt heads were on the inside of the frame, it could look like the Novara Gotham. Or they could have an equivalent design.

I'm looking at the gap between the welds above and I think there's a faint stripe in a slightly different colour, suggesting a centimetre wide chunk gets unbolted from the seat tube. But it's very, very faint.


Commuter bike for better performance: less weight, or internal gear-hub?

When you use your bike every day, reliability is as important as weight.
I use 2 bikes, with a train ride in between. The bike I use at my work town rarely gets maintained. I take it home 2 times each year. The only things I do regularly is pump the tires and lubricate the chain. Even then it keep riding as good as new. The derailer bike I had here before that needed a lot more care.

The things I learned over the past years:

The simpler the better. If the terrain is flat enough to get by with a bike without gears, do so. 80m elevation is on the edge, and depends on your physical condition. If you feel the upper gear on a Nexus 8 is not large enough, you're riding quite fast (35Km/h+) already. I ride a bike with an Alfine 11, and have no problem doing 35 in 8th gear. Another thing is adjusting your style to spin faster (85+RPM), which generally is also better on the knees.
No front shock absorber. The good ones are too expensive, and the other ones too heavy and crap
No V-brakes or cantilever brakes. At least hydraulic rim (Magura) or disc brakes
Mudguard!
A rack to hang bags (I am very happy with bags like this). No backpacks for me.
A IGH is a lot more carefree then a derailer.
being able to shift at red lights is very handy
The lights have to be driven by a dynamo and fixed to the bike (battery lights get empty or forgotten at the worst possible time)
No NuVinci. It is heavy, and you can't shift when stationary

So I would not use either of the bikes you suggested, but something like this or this

I don't have an opinion on chain vs belt. My girlfriend has a bike with a belt, and that tends to stay cleaner then the chain on my bike, but I don't know whether it is worth the extra expense.


Diagnosing the cause of clicking sound coming from drivetrain

Your noise is pretty loud and constant. It suggests something is worn out. It's possible there's some interface that needs cleaning and greasing, but with Shimano road BBs, that usually won't produce a noise so constant and obnoxious. This is what I would do:

Pull the cranks and wipe the grit off everything, and also wipe down the contact surfaces of the spindle.
Check that the BB isn't overtly worn/gritty feeling. 5 years of riding is an ample lifespan for Shimano external threaded BBs, and they're inexpensive to replace.
BB cups torqued.
Chainring bolts torqued (this isn't it if you're sure it's only from left side pressure).
Light grease cooating on the the black BB top hats in the spindle contact area. Shove the spindle through. Don't grease the spindle itself because it will squeegee into a big mess on the drive side. Grease the inside the of the splines on the left. Install the left side, adjust so the play is just gone, torque down both bolts to 14Nm in a row. (Or, sans torque wrench, make them both as tight as you would ever reasonably tighten something with a 5mm L-wrench.)
If that doesn't do it, test with different pedals. Alternately, sometimes you can get this right off the bat by applying pressure to the left crank at the end of the crank arm, getting no noise, and then applying similar force to the pedal and getting obvious noise.


You need to be very careful with the weight limit on that rack, it will flop about if overloaded a little, or break if overloaded too much. But you're riding short distances in heavily populated areas, so presumably you're staying in buildings and buying prepared food, so you don't need to carry much. If you can afford to spend a little extra money on buses etc, there's very little risk so the best bet is to try it and see.

As Renesis pointed out in comments, while google maps is pretty good at navigation, you do need to select the "bicycle" option rather than the default car one. Otherwise you'll be stuck at the first autobahn you come to when you get to the "no bicycles past this point" sign :) But your route is likely to be somewhat longer than 500km, but significantly more scenic.

I would take a windbreaker, long pants and a shirt, underwear, toiletries, phone charger, phone and wallet. That's about it. Wash your cycling knicks every night and dry them on the end of your bed if there's no other facilities. If you have light cotton pants and shirt they crumple up to very little space.

The main thing with your first tour is that you get out and ride. If something goes wrong jump on a bus and either continue your tour as a bus-traveller, or go home. It's no big deal, the idea is to learn what works. The big planning exercise is probably going to be booking accommodation :)

I suggest reading random cycle touring sites and travelogues to get an idea of what people do and how they travel, in the area where you're likely to be riding. You have everything from the Paris-Best-Paris style randonneur "carry nothing" tourists to four wheel "bicycle campervan"travellers in the low countries of Europe, so there's a lot of different options you can choose. But the easy one is definitely how you're starting - get a bike, pack a change of clothes, and ride.


What are the benefits of *rigid* lefty fork?

One obvious advantage for most lefty bikes is

You’re able to change the tire and tube without taking the wheel off the bike. So wheel adjustments and repair can be made without interfering with the disk brake rotor. This is especially useful on rear wheels as you also don’t have to take off the chain.

In the case of these rental bikes, I suspect that the real reasons are:

Most everything on these rentals that can be made non-standard is — from the head tube diameter to the axle width. This slightly lessens the risk that the bikes will be stolen to be stripped down for parts.
Branding and theft reduction: The bikes are highly visible and recognizable even if they are repainted


Looking for a first race worthy road bike - What should I look for?

My recommendation is to buy a used bike on Craigslist or eBay first. Many people will vehemently disagree on the best manufacturer, component group, frame material, etc., but the best advice I can give is to buy a cheaper bike that you can use until you decide upon what you actually want. This is doubly important because the things you think are important to you in a bike right now will likely change within a month or two of actually riding.

With that said, my advice is to ignore the manufacturer. Go with a Shimano 105-level or equivalent groupset. SRAM Rival/Apex or Campagnolo Veloce are similar. Campagnolo parts are harder to find (in the U.S. at least), so I'd lean slightly more towards SRAM or Shimano. Try both systems out, and decide which you prefer. Regardless, go with an entry-level groupset. There's little advantage to an expensive one for a novice rider.

Ignore the wheels. Whatever wheels come on the bike will be good enough to get you started and they can always be upgraded later. And don't get caught up on carbon versus aluminum versus steel. Whichever happens to be on the bike you like best that's in your price range will suit you fine. You're just starting out; buy expensive things only after you've been on the bike awhile. Chasing performance with expensive parts is a fool's game. The engine matters much more than the bike does.

Last, get fitted and make sure you're buying a bike that's well suited towards your body. A bike that doesn't fit will make you uncomfortable and hurt your performance.

And don't feel like you need to spend the full $3,000 right out of the gate. $1,500 now leaves $1,500 left over when you decide cycling isn't for you. Or $1,500 for upgrades when you decide you'd rather do nothing but ride and know exactly what you want. The difference between a $1,500 bike and a $3,000 one is probably less than you think. Again, the engine is what matters.


How to mount Galaxy S3 on a mountain bike

You're going to have to go with something purpose made for that specific model of phone to get a secure mount on the bike. I'm not aware of any universal phone mount options that are worth anything, however you can browse Wally World if you feel like wagering $20 one yourself. There are few different brands, but the Bracketron universal mount has sealed/waterproof zippers whereas the Arkon does not. I can tell you from personal experience that the Arkon universal car mount I have has had to be Frankensteined back into working condition about 4 different times over the last several years, so I don't have a lot of faith in their products.


UCI Regulations for Track cycling provide a very loose definition for velodromes (see page 75) even up to the Olympic level. The only strict requirements beyond track width and markings are that velodromes must be 133-500m long (250m exactly for Olympic events), the track shape should consist of two parallel straights connected by two bends and that there is a smooth transition between the straights and the bends. There is no requirement for a consistent radius or banking throughout each bend. There is no requirement that the straights should be the same length or relative elevation either.

Exact dimensions of various velodromes are difficult to find, however to give one example How the velodrome found its form features an interview with the engineers responsible for the velodrome used for the London 2012 games where they note:

  The track in the London Velodrome doesn't have the usual reflection symmetry you find in buildings. "If you folded the track in half lengthwise, the two halves wouldn't match," says Weir. The track does have rotational symmetry, it looks the same if you spin it by a half-turn. But the slope of the track going into and out of the turns is not the same. "This is simply because you always cycle the same way around the track, and you go shallower into the turn and steeper out of it."

While it is likely that most velodromes feature rotational symmetry and many of those will also feature reflective symmetry this is not a requirement for a UCI homologated track.


Chips in carbon frame - how worried should I be?

These appear to be paint chips in areas of the bike where rock strikes are common.  I don't see any evidence of delamination--a separation of the carbon fiber weave and thus carbon fiber damage. However, no amount of photo inspection can replace a hands on one.  Were I to purchase a carbon fiber second hand, I would have a second opinion of the carbon fiber integrity done by my local bike shop or equivalent expert.
Paint chips can be covered with a similar colored nail polish or other suitable paint. There are many companies in the U.S. that offer carbon fiber frame repair if it is determined the actual carbon fiber is damaged and you already own the bike.


If she liked the Lime, why not look at the second hand market. Get one and have it serviced by a good bike shop and off she goes...

Edit : Quick 1 minute search and I found This - why go second hand.....


The Ultegra 6600 STI lever is available as a right hand only part. It should cost around $400 dollars for the right shifter only, and around $600 dollars for the set.

Any Shimano 10 speed rear shifter, including the new Tiagra 4600 10 speed will be compatible. If you have current brakes, and you use a 10 speed STI lever, as previously noted, you will have no problem with the brake pull.

The compatibility chart can be found here.


Nashbar's specs for the rim list the inner width as 16mm.
http://www.nashbar.com/bikes/Product_10053_10052_566766_-1___
(click the "Specs" link)

This is a fairly standard width for road wheels, so you should be able to safely run any common road tire size (21mm-35mm give or take a few mm).


Bottom bracket cup doesn't fit on non drive side

Is it possible that you bought an Italian threaded bottom bracket for an English shell or vice versa?

For the two scenarios above, compare the two cups of each bottom bracket to themselves (ie old to old, new to new) by placing them outside down on a flat surface. Now look at the threads. Do they pitch in the same direction or opposite? If the threads pitch in opposite directions then you have an English bottom bracket, which is more common. If they pitch in the same direction, you have an Italian bottom bracket, which is less common, but can be mistaken for English as the drive side cup has the same pitch and TPI as an English drive side cup- the width is just a little different. Here's the best ASCII diagram I can muster:

Italian drive side
||
||/////|
||/////|
||/////|
||

Italian non drive side (same thread direction as drive side)
||
||/////|
||/////|
||/////|
||

----------------------

English drive side
||
||/////|
||/////|
||/////|
||

English non drive side (opposite thread direction as drive side)
||
||\\\\\|
||\\\\\|
||\\\\\|
||

It would be easy to mistake an Italian BB for an English one (or the other way around) as the drive side cup would thread in fine and the width is very similar. Once you get to the non drive side is where you would run into trouble, which matches up pretty well with the problem you described.


Is it possible to service rear derailleur pulleys?

Yes, the pulleys of your rear derailleur can easily be removed, cleaned, greased, and re-lubricated. I'd recommend doing so about every 500 miles depending on your climate or whenever they start to sound gritty again.

If you haven't yet, I recommend reading all the Park Tool drivetrain care topics.

Steps 9 through 13 particularly on this page should cover the pulleys:

https://www.parktool.com/blog/repair-help/rear-derailleur-overhaul


Broken glass on the bicycle path, what to do?

There are three approaches you can use in combination.

Preparation

Tough tires - people have their favorite puncture-proof tires. Kevlar reinforced tires work pretty well.

Hard tires - pump your tires to close to the maximum pressure written on the side wall. This definitely reduces punctures, and can be combined with puncture-proof tires.

At the time

You limit your question "reducing punctures while [riding] though glass". Obviously, if you could avoid the trash you would.

You cannot always go around the trash. If you are able, you could bunny hop over it. This is also not always possible when commuting, due to lack of time, heavy traffic (including other bikes) limiting your options, or carrying a pack or panniers.

Slowing down is often also not an option when commuting because of following traffic.

After the fact

Brush your tires. It should be acknowledged that there are some who are squeamish about this. But it is very effective at removing foreign objects from your tires. In 35 years since I learned to do it, I've never (seriously) hurt my hand. Of course you should wear gloves. Most gloves have a reinforced patch across the palm to the base of the thumb for this purpose. (Many people mistake this for extra padding :-)

Don't wait: as soon as you hit the trash start brushing your tires. The more revolutions your tires do, the more the trash gets hammered into them. So brush them strait away. It doesn't help to stop to do it; firstly, it interrupts your ride, but mainly because by the time you stop the damage is done.

For the front tire, place your palm (near the base of your thumb) gently on the top of the rotating tire, in front of the brakes. The tire surface must be moving away from anything you could catch your hand in. You only need to keep it there for a few seconds, enough for one or maybe two revolutions of the wheel. Sometimes you feel a slight bump when you have successfully removed something from the tire. Usually, you'll feel nothing.

The back tire is a bit harder to brush, because you have to reach down to an awkward place and if you have to look it means you're not looking where you're going. So you'll want to practice this skill before you use it in traffic. Again, brush your tire in front of the brakes, in front of the back stay, where the tire is moving away from the brakes. Because of the low clearance between the back tire and the down tube on most race bikes, you need to be careful not to let you hand get pulled down into the gap. That hurts. Also avoid poking your finger into the spokes. That hurts too.

After reading this you can see why some people avoid doing it. Just be careful while you are learning, and practice before doing it in traffic. It's a valuable skill to have.


It's pretty easy/light to carry around a couple extra spokes per wheel and a pretty good idea for a long tour.  You'll probably need a few different lengths though for the front, rear left, and rear right sides.

Another good option is to carry an emergency fiberfix spoke that can be used with most wheels, which will help in an emergency.

http://www.amazon.com/FiberFix-Emergency-Spoke-Replacement-Kit/dp/B001GSMQZC

You may want to work on your skills with truing a wheel without a stand as well. You can use a couple zip ties on your seat stays in place of a truing stand. Just make sure you are comfortable with this process before you go on the road, and don't forget your spoke wrench.  You may need a cassette tool / chain whip as well if you need to replace a spoke on that side of the rear wheel.


What is year and model of my Diamondback?

Check out this thread, the bike in question matches "F4042" S/N portion with yours. According to messages, your bike was built by Formosa in Taiwan (F) in 1984 (4), so it's not Formula One, which was made in Japan. This post mentions that "Viper, Pacer 500 & Super Streak were available that year", but an archived copy of os-db reveals there were also Harry Leary, Super Streak, Super Viper and Viper.

To narrow the options down further, you can:

Visit all links above and see what matches your bike features the most.
Post photos here, especially serial number, dropouts, rear brake bridge. Full side shot would be good too.

I'm inclined to believe it's a 1984 Super Streak because 5 out of 8 serial number symbols match.


possible upgrades for merida speeder 200

All Shimano road derailleurs (2400, Claris, Tiagra, 105, Ultegra, DuraAce) made for 7-10 speeds are compatible with eachother. The amount that the derailleur moves is determined by the shifter.  With 11 speed they changed things up, so as long as the derailleur you chose was designed to work with 7-10 speeds you should be fine. For mountain derailleurs (Acera, Alivio, Deore) 7-9 speed derailleurs are compatible with the 7-10 road groupsets.

A 9 speed Ultegra or even DuraAce can be found at 9 speeds if you find old enough equipment, but all current 105, Ultegra, and DuraAce are 11 speed and will therefore not be compatible with your current 9 speed setup.  If you want to find a 105  9 or 10 speed derailleur, it won't be the current model, although the 10 speed 105 (5700), Ultegra (6700), or DuraAce (7900) is still readily available as a replacement part.

As an aside, are you sure that upgrading the derailleur will really fix your problem? What kind of problems are you having with the Tiagra? Could it be an adjustment or bad cabling that's causing your shifting problems?  Is your cassette or chain worn? 9 speed Tiagra is older equipment and it's possible that your chain or cassette are at the point where they should be replaced. I have 2400 (8 speed) level equipment, and find that it shifts quite well as long as the adjustment is good, and I usually don't need to adjust it very often.


BB spindle length/chainline for re-used Shimano FC-M391 chainset

The spindle length depends on your frame and on the used crank. The combination of those two will dictate your chainline which should be 47.5mm.
In some cases it can be 47.5-50mm ( see https://www.sheldonbrown.com/chainline.html )
There are also chainlines for other types of bike, the 47.5mm are for Mountain Bikes.

You can measure your current chainline and then calculate the spindle length you need based on the current chainline and spindle lenghth. So for example if you now got a chainline of 52.5mm and need 47.5mm your BB spindle should be 10mm shorter to achieve this.


DNM USD-6 fork service intervals and procedures

The manual linked in the comments states that the fork should be serviced every 10 months, every year or every two years, depending on its usage conditions, at an authorized shop.

The service intervals are expressed in terms of months of owning rather than in riding hours. However, the suggested maintenance intervals lie in the expected order of magnitude for values for how often people service their forks in the real world (from twice a year to once in two years, depending on the usage).


Does a three foot passing law actually require drivers to give three feet?

This may not seem very concrete to you, but if you think about it, it is very powerful indeed.

Imagine a collision between a car and a bike. With no such law in place you might expect there to be some argument about whose fault it was etc. etc. and as cyclists we all know from experience who's likely to come off worst...

However you put such a law in place and when you have a collision, the motorist has broken the law by default because they couldn't have been the required distance. I'm sure there would be circumstances where the motorist could argue that the cyclist was riding like a dick, but they would be forced to make that argument, you wouldn't start from a 50/50 position.

People have been talking about this kind of thing in the UK for years in order to make cycling safer, but nothing has ever been done. In fact I think this is the first form of words I've seen that achieves this goal.


I would agree with Daniel about the cartridge style BB. Just make sure whatever cranks you get that they're compatible. One thing to think about with bonding, if you plan to use carbon fibre you will need to do some form of barrier layer to protect the steel, otherwise overtime the carbon and steel will have a chemical reaction that causes corrosion.  Applies to any carbon and steel bonds, not just the BB shell.


Do I have to simply wait for google maps to add cycling directions to my area? Or can I help?

Have a look at http://www.opencyclemap.org/ it uses the http://www.openstreetmap.org/ data, so you can help them by mapping your local cycle ways.


Adjusting rear derailleur - shifts to lower gear, but not to higher

Perhaps your shifter cable can't slide smoothly. Shift to the tallest gear (smallest cog). Pop the shifter housing out of the brazed-on stops. Slide the housing back and forth and look for stiffness. Put some lube in the housing and slide it back and forth to distribute it.

Perhaps your derailleur hanger is bent. A bike shop will have a tool to easily check its alignment.

If either of these is a factor, then you will never be able to adjust your shifting properly.


Turning right but can't see cars coming (UK)

It's not easy.  A few factors make it harder.

The double yellow lines don't extend vary far up Chipperfield Road (for those not in the UK, they mean "no parking").
Cars can come up too quickly for the conditions, and taxi drivers are notoriously impatient, as well as likely to pass too close without slowing down.  Seeing a hazard rolling out of the junction the driver should have slowed and prepared to stop even if you were being stupid (which you weren't).
Electric cars at urban speeds can be very quiet, easily drowned out by general traffic noise from further away.  Like you I use my ears a lot when riding.
In the dark, modern streetlights remove a cue I used to use - the reflection of white headlights on the road lit by orange lights was the first sign of cars at one junction I ride regularly.

That said there are a few things you can do.

First you need to be aware of your lines of sight, and when they will open up.  So as you roll forwards, you need to be looking right when you can see past the parked cars.  And not just past but through and over them.
Look for vehicles coming from the left further away.  If the road is only wide enough for one car, have they stopped to let someone through?
You may need to stop suddenly, put your feet down, and take a step back.
Eventually though, you may be committed to going - do so decisively.  Pedalling hard for a couple of seconds doesn't just accelerate you, it signals that you're definitely moving.

Standing up on the pedals raises your head (only a little because you've got to hold the bars), helping you see and maybe even be seen, but you'll probably roll a little further before you can put your foot down.  I'd stay seated, unclipped from the pedals, but I'm tall and choose pedals that I can clip to but can ride gently without clipping in.
The problem with getting off is that by the time you get back on things have changed.  The only thing to do then is cross on foot and rejoin.  That shouldn't be necessary here, but it's always a valid option


You want to get the housings situated closer to the frame so there's room to put your bag in front.
They curve pretty far into that space now. To get them as tucked as possible:

Don't zip tie them together like that.
If your STI model is one that has two routing options for the shift housings, use the one that puts them behind the bar.
You can route the brake housings (as well as the shift if the above option doesn't exist) so that under the tape they slope downward, and then exit around the 6 o'clock position on the bar, rather than in front like they do now.
Make them all as short as possible. They don't look like they are now. This is usually defined as the minimum length to still have some slack when the bars are turned as far as they're able in either direction.
Corroborate that you can't cross the shift cables under the downtube (usually not possible with this style and location of stops). If you can, doing it that way may make the housings protrude less.

The bag you have isn't made to work with a handlebar bag rack and decaleur, but eliminating this kind of problem is one of the things they do, along with the sorts of handlebar bags they're used with. They could also provide a better place to mount the light as well.
For the light, if the above doesn't get the housing out of the way, one avenue is switch to metal fenders, use a bracket to get the light all the way forward on them, and put an additional strut behind it for stability. A number of old and new rando bikes have this sort of thing. There's even now an off the shelf product that does it. Do not forego the additional stabilization of either a strut or a rack, and don't do it with plastic fenders.


How to properly ride over ripples on gravel roads (washboards)?

stand on pedals
knees bent (not straight) keeping your butt 10-20cm from the seat
your hands should be very relaxed on the handlebars (your body should be supported 95% with feet and just 5% with hands)
keep your back straight (do not hunchback)
look ahead
enjoy

This works on all bicycles.

sketch from http://www.amazon.com/Mastering-Mountain-Bike-Skills-Edition/dp/0736083715


Getting the best fitted mudguards for a standard road bike

Specific product recommendations are off-topic here.  With regard to bike fenders, though, there are several things to consider.  Fit is perhaps the most important -- the fenders must not only fit but provide reasonable clearance for the tires you may be using (keeping in mind that lugged tires need much more clearance).

After that you need to consider the ease/robustness of the mounting system, the robustness of the fender as a whole, and the coverage provided.

With regard to clearance, one thing you need to do is figure out the actual diameter and width of the tires you will be using and compare that to the fender specs.  The couple of times I've bought fenders online this has worked for me.

Added:  One important thing to consider is toe clearance on the front fender.  Usually any fender will result in some minor toe clearance issues, but there's a difference between your toe occasionally brushing the flexible plastic fender and your foot jamming against an oversized stiff metal fender.

And another thing:  If you have plans to ride in the snow then either avoid fenders entirely or get ones that are easily removed.  In the right connditions snow will quickly become jammed between tire and fender and make you grind to a halt.


My Road bike pedals locked up tonight. Why?

If you didn't notice any broken spokes, it could have also been that the bead of the tire popped off the rim and caught on the brakes, preventing the wheel from moving and then ultimately dragging on the ground causing a blowout and maybe warping the rim.  Once the tube popped, it would no longer be pushing the tire in to the brakes and allowing your wheel to spin freely again.


How does a chainstay length affect a mountain bike performance? (wrt: 26", 650B, 29r)

All else being equal, longer chainstays equate to a longer wheelbase, and the rear wheel trailing further behind you. You are correct in your assertion that as wheel size increases so too does chainstay length, though many manufacturers have put considerable effort into minimizing this and as such the increased chainstay length is not directly proportional to increased wheel radius. For example, a 26" and 29" version of the same bike model are unlikely to have an inch and a half discrepancy in chainstay length. That said, there are tradeoffs to be had in chainstay length differences.

As an analogy, think of a drag strip or hill climbing motorcycle vs a standard sport or dirt bike. The first two examples have very elongated swingarms that put the rear tire well behind the rider and dramatically increase the wheelbase. Those long swingarms are great for preventing the bike from looping out and maintaining straight line stability, but neither can turn or corner like the latter standard motorcycle examples. That is a very exaggerated example, but the same principles apply to chainstay length differences on bicycles. Again, all else being equal, longer chainstays are going to be more stable at speed and typically provide better climbing traction, but they will cause the bike to not handle as sharply and to no turn as quickly- that much is just basic physics.

Keep in mind that chainstay length and wheelbase are just two factors in a multitude that determine how a bike will handle. Also keep in mind that just because you have a bike with slightly longer chainstays doesn't mean you can't rail corners or navigate switchbacks, and just because you have shorter chainstays doesn't mean you can't bomb descents- much of this comes down to technique, and you'll alter your technique to accommodate for any differences in your bike's handling characteristics.


How to cross major road 3 way intersection

Options in order of preference:

Another route.
Stop on the south side, wait for straight though (north/south) traffic to stop, choose your time to cross contending only with single right turn lane out of PonyExpress Parkway. (Turning traffic is slower, minimizes damage if you get hit). If you don't make it all the way across before lights change, you are in the left turn lane for the next phase.
Be assertive and use the left turn lane but only if its a cycling friendly town. problem with this move is at 50MPH, if it goes wrong, it goes badly wrong.

Also Lobby local authority to make it safer. They have gone to expense installing cycle lanes, so they should at least give you a fair hearing.


Is cycling in the Netherlands without a helmet safer than cycling with a helmet in the USA?

There's a simple answer to the question you didn't actually ask: in the Netherlands cyclists who wear helmets are much more likely to be hospitalised than those who don't

Although the Netherlands is probably the safest country in the world for cycling, helmet wearing among Dutch cyclists is rare. It has been estimated that only about 0.5 percent of cyclists in the Netherlands are helmeted.
However, according to Dutch Government data (Rijkswaterstaat, 2008), 13.3 percent of cyclists admitted to hospital were wearing helmets when they were injured. Why does wearing a helmet appear to increase the risk of being injured so substantially?
The answer is probably related to another statistic. Of the injured cyclists wearing helmets, 50 percent were riding mountain bikes and 46 percent were riding racing bikes (Rijkswaterstaat, 2008). In other words, most helmeted cyclists in the Netherlands are engaged in a competitive activity, with very few making utility trips on the traditional style of Dutch bicycle.

I can't find a useful answer because of that. I couldn't find statistics that answer "of the less than 1% of utility cyclists who wear helmets, how many were killed or injured"?
Of course, having so many people riding bikes on the roads also means that of the people killed on the roads, a high proportion are cyclists (about one third). The Netherlands is also the safest place in Europe to use the roads (45 deaths/million pop, cf 145 in Greece which is the worst in Europe and 147 in the USA).
What that means is that in The Netherlands about 185 cyclists die every year compared to 700-odd in the USA (~4x as many, thanks whatsisname). There are more than twenty times as many people in the USA... but more trips by bicycle in the Netherlands. You're still safer there than any inhabited part of the USA. You're safer on a bike in The Netherlands than in a car in the USA, even just looking at immediate crash danger rather than life expectancy (the lifetime risk of death remains 100%, obviously).
There are some amusing results of that:

After a recent decline in the murder rate, you are now fractionally more likely to die while biking than to be murdered in the Netherlands!

In Amsterdam, you're still more likely to be murdered, though.

You're also more likely to die by murder in the U.S. as a whole than by biking in the Netherlands.

You are also more likely to drown here than either die biking or be murdered, especially if you are a child.

My suggestion is to look at it the other way: if you-the-parents insist that your daughter wear a helmet while cycling, will she keep cycling? Will she be unhappy that her mother would prefer her be socially ostracised than even try to fit into the new culture? Will she just observe that her parents are failing to assimilate and reject them, rather than everyone she knows?
Also try flipping it - how would your wife deal with someone who moved to rural USA and didn't want their daughter to learn to drive? Or insisted that she only travel in the Smart car, since that's the safest small car and it's what her parents had back home in the Netherlands?


You will need a specialty tool referred to as a crank remover or crank extractor. A Park Tool CCP22 or something similar. I would suggest considering the Park Tool CWP7 or equivalent as it offers increased flexibility. While the CCP22 is suggested for square shaft interface the CWP7 will do square, splined and octolink. While you only need the square type now the universal design of the CWP7 may come in handy later.


A worn, stretched chain will accelerate wear on sprocket and chainring teeth. There will then be a greater chance that the chain will slip off of and override the sprocket teeth as you apply a power stroke through the crank. When this happens the pedal and your foot suddenly slips downward, which could throw you off the bike, especially if you were off the saddle and standing on the pedals.

A new chain is not usually regarded as a 'great cost'. They are not cheap but not expensive either. There's no reason you need a new wheel, unless there are other problems of course. You probably do need a new cassette though.

Whether you need to replace the chain and cassette depends on your situation, your bike and how you ride. If you have a quality bike, do a lot of miles and want an efficient drivetrain you absolutely should replace it. If you do a few casual miles occasionally and are not experiencing any problems you can probably get away with leaving it as it is.


Reach Adjust on Shimano hydraulic brake levers for MTB flat bar

Reach adjust is though a small (2.5mm?) hex key on the 'inside' of the lever. The MT400's definitely have it.
The amount of reach adjustment is quite wide, On my MT400's, from memory you can adjust it down until the lever very nearly hits the bars before the brakes are fully applied, so will be as good as can be for a child. Higher end brakes have better performance and adjustments like free stroke, that might help those small hands, but the price/performance/reliability of the MT400's or 315's is impossible to beat.
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Interupter brake lever compatible with hydraulic mechanical disk brakes?

Those brakes are designed for cyclocross which means using STI "brifters" as you no doubt have on your bike.  Interrupter levers are also designed for use with STI levers.  The trio should be perfectly compatible.

One exception to the above would be if you had "mountain" brakes designed for MTB levers.  But that's not the case here.


Run a Shimano STX derailleur with 8 speed cassette or bigger?

Basically all the <=9 speed Shimano rear derailleurs are compatible with the <=9 speed Shimano shifters (excluding some old Dura-ace and a few other weird exceptions). So, you need to match:

1) Being within the capacities of the derailleur (max tooth, min tooth, chain capacity -- based on the chainring and cog sizes)

2) # of speeds on the shifter = # of cogs on the cassette

As for needing a bigger hub, check that your hub is indeed a 7 speed hub; if so, you need a new hub (which a new wheel would likely be the upgrade route), but a lot of people have 7 speed cassettes on 8/9 speed hubs.

Note that the cost of the new wheel may make the upgrade route not worth it economically (you're looking at the cost of a new shifter, new cassette, new chain and a new wheel).

Based on the derailleur, the bike is probably close to 24 years old at this point, which makes it questionable to do these upgrades at all (and likely that you have an actual 7 speed cassette wheel, or maybe even a freewheel based bike, which would require an 8 speed freewheel or a new cassette wheel). I'd advise getting a newer bike from the get go instead and leaving this the way it is, if you want to do a 1x8 conversion.

Also, there are other smokey grey derailleurs on the market from Shimano (e.g. in the Acera line).


Wider tires are the first thing to try. The BadBoys are basically rigid mountain bikes with 622mm wheels and narrow tires, so you could also put on mountain bike sized wheels and very wide tires. With a second set of wheels, it's easy to change between road and off-road riding.

About suspension forks, with current geometry there isn't much room for the suspension to work. You could install a 29" suspension fork, but that would change the bike's geometry.


Unfortunately the answer is the same as how you judge the quality of any product. Experience with the product, brand reputation, price (higher correlates somewhat with better performance) and searching for and reading reviews.

With respect to your current tires, they are probably not worn out. Not even cheap tires wear out after only 750kms. Road tires have a very shallow 'tread' pattern that is really just cosmetic - bike tires are narrow enough to displace water easily and do not need tread to grip tarmac or concrete surface. See How do I know when to replace my tires?.

Also, you should know that higher inflation pressure does not necessarily mean lower rolling resistance on rough surfaces. See this answer and this GCN video.


What is the actual size of a 26x1.5/2.2 tube?

Tubes expand quite a lot as they are inflated - Try pumping one up on its own and see how quickly if expands (don't over do it unless you never want to use the tube again.). The way tubes and tires work, the tube holds the air in, the tire prevents the tube expanding.

The 1.5-2.2 means the tube is suitable for a tire 1.5 up to 2.2 and is ideal for you 2.1 tire.


Baby seat for stoker's seat post on tandem

I don't know of a child seat which replaces the seat-post and I think it's unlikely that it exists as a product as this would be such an unusual case. The normal Hamax seats which attach to the seat tube will work fine and the design shown here provides some suspension.

I've ridden the bike like this, without a stoker and it does take some extra care due to the weight high up, especially at low speed and when pushing/parking the bike. In this photo I have the rear brake locked on with a strap, to stop the bike slipping. If you were certain you'd never have a stoker riding then, depending on the frame design, you could probably attach it to the captain's seat tube, but on a tandem it can be helpful to have a bit of weight over the back wheel for traction.

I know that doesn't exactly answer your question, but hopefully it's some help.


I don't believe you have much success in selecting a suspension fork. Looking at the bike, a suspension fork with exactly same geometry as yours would have approximately zero suspension. There is simply no room for a suspension fork with unchanged geometry. If you change to a suspension fork, it will change the geometry of your bike which will affect the steering characteristics. For example, the seat tube angle is changed (so you may run out of fore/aft adjustment in your seat post), the head tube angle is changed (so the fork trail affecting the steering characteristics will probably not be what the fork manufacturer intended), the bottom bracket height will change (so you will find it harder to mount and dismount due to increased bottom bracket height).
Every frame will have different requirements for a fork. If you see a fork, you need to carefully look at its dimensions and analyze what the fork trail will be and how the bottom bracket height and seat tube angle will change. Only with such an analysis can you determine if the new geometry of the frame/fork combination is acceptable.
A bike frame designed for suspension would have reduced head tube height from the lower end, making room for suspension below the head tube. For such a frame, the intended fork length is longer.


Have you tried changing the tension on the shifting cable? There's usually a tension adjuster on the outside of the hub. It's unlikely to hurt, and it's easy to do. I'd tighten a little at a time until all the gears work well.

If that doesn't do it, you may need to have the hub looked at. There could be some dirt inside the hub (it happens, even with "sealed" units.) Or it could be a mechanical issue; getting an internally geared hub fixed can take time and money. If you end up doing this, I'd look for a shop that knows what it's doing; it can be a little tricky.


The yoke spacing on the BOB Trailer is quite a bit wider then a typical front fork mount bike rack, you could probably modify one with wider spacers and use a trailer skewer (or similar fabricated part) to mount the trailer yoke.  The wheel tray will need to be long enough for the span of the trailer and the fork mount will need to be high enough (or the tray low enough) otherwise the trailer will stall on the wheel tray when you try to mount the trailer yoke in the fork mount of the bike rack.

I had an extra roof top, frame clamping, bike rack on hand so I designed and fabricated a bracket that combines the yoke mounting of the trailer with the roof top mounting of the bike rack so it mounts to anything in the same way that the roof top bike racks mount:


We can make this easy... Lets assume your frame is totally straight and not bent in anyway.

Measure front chainline.  Chainline is the distance the chain is from the bike's centerline.  You will need an inexpensive machinist's scale .  A machinist scale is just a small 6" long ruler. On a machinist's scale the zero mark is exactly at the edge of the scale.

Measure the front chainline from the edge of the seat tube.  To that number add the radius of the seat tube.  My seat tube is 28mm in diameter, half of that is the radius. My front chainline is at 14 + 34 = 48mm

For the rear chainline you measure from the inner edge of the dropout to the gear. You know the width of your rear hub (135mm) and you subtract the measurement.  (oops.. my rear hubs are 135mm yours are 120mm, right?  Obviously you should use your measurements! ) In my case, the chainline to that center gear is 135/2 - 24.5mm (from photo) = 43mm   Remember the chainline is the distance between the chain and the CENTER of the bicycle.

Obviously my bike is using a derailleur so I'm not freaking out about a slight mismatch.

Does that help?  If you know where you are, you can then make changes to the front crankset with shims to adjust chainline a bit. Depending on which hubs you use, you can do some spacing work at the rear as well.  Easiest combo is a multigear hub used for a single speed with a Surly hub spacer kit.  That makes it all easy.

That cheap machinist scale takes all the guesswork out of the conversation.  Do note, because of how cranksets mate to the crankarm and bottom bracket, its almost impossible to pre-determine chainline from parts sitting on a table. You have to install them on a bike to the correct installation torque, then do your measurements, then take it all apart to make adjustments as necessary.

And Sheldon Brown, although he has passed away now (sigh), is still your friend.

http://sheldonbrown.com/chainline.html

One more comment: Are you really trying to use a 120mm wide rear hub on a 135mm frame?  I don't think that's a clever idea.  5mm off, okay.  That far off, you risk bending the frame.  Yes, you could convert that 120mm wide rear hub to an effective 135 with spacers and a long axle.  If you are going to do that please purchase SOLID axles intended for a 135 hub.  With the loading from a 120mm wide hub a hollow skewer axle probably won't cut it.


Ebike chain vs regular chain for up to 350w Mid Drive

I don’t think you need an eBike specific chain. Pro cyclists can achieve 1000W and huge torque in a sprint and they use lightweight road bike chains. Even with a 350W motor you are unlikely to reach similar levels.
It looks like the e10 has beefier pins with "mushroom" riveting. The weight is basically identical (2.34g vs. 2.35g per link) and both have nickel plating.
Doesn’t look like it would make a difference. I think it’s merely a way for KMC to make more money with "eBike specific" parts. The same can be seen with eBike specific tires.


Do GPS computers always need online account

Depends what you want to do with the information.

If you just want to see your location on screen and nothing more, then no online account is required.

However if you want to push your ride recording/location to a service like strava etc, then you'll need an account with them.

The device maker would want your information for registering the device, and warranty.  That would be a different matter, but doing this may give you access to firmware and map updates.

Finally, if your device wants internet access but has no internal cellular SIM, it might pair with a cellphone via bluetooth etc, to get internet access.  This is often done through an app on the phone.  Or you have to wait till you get home in range of a wireless AP to upload the device's recording.

I don't have a garmin personally, I use an android phone with ANT+ to talk with a HRM and a Cadence sensor.  The phone has a data internet link when in-range, and also has wireless ethernet when I'm at home.

I need a strava account, and a cellphone account, and a working internet connection at home.