Frame Or Paint Crack (Cannondale Super Six Carbon)

Since it's a few seconds with an allen key to pop the stem off and have a look at the inside of the head tube, I suggest doing that. Strongly suggest. If there's any damage to the fibres, or the cracks go deeper than the gel coat, don't buy the bike. If you don't know what that means, or the seller won't let you look, don't buy the bike. Exposed fibres or cracks on the inside of the frame might be fixable, but not by you (or you'd know enough that you wouldn't need to ask your question here, you'd be answering it instead). But they are probably not fixable.

The failure mode here is most likely that the head tube will break, probably when you're braking heavily. That's not a good crash to have, you can easily end up with severe dental trauma and that can never be fixed. Break an arm, grind half the skin off your face or hand, it hurts but those things grow back. Teeth don't. My partner has an expensive bridge where her front teeth used to be, and when we can spare $20,000 we will get them fixed better. Not fixed properly, because no-one can currently do that for any price, but something better than the "temporary bridge" that has been there for 10 years.

The trouble with buying something when you don't have a close relationship with the seller is that you have no idea whether it's really a good deal (if so, why doesn't the seller have any friends that will take the good deal?), or whether you're the gimp. Especially with carbon fibre and other materials that can fail in non-obvious ways, a common reason to sell is that the bike has failed in some way that's not going to be easy for the buyer to tell before they buy it.

The other obvious reason for a "good deal" is stolen property. Grab the serial number and search online for it, including the various stolen bike registries. You might be surprised at what comes up.


Speed is determined only by gearing, of which crank, cassette, wheel, and tire are components

Any 2 bikes using, say, 42t cranks with a rear 32t cog and 25c tires on 700c wheels at 90rpm will be going the same speed. Bike type and size, rider/bike weight, and even front wheel/tire size and crank length don’t matter. These other factors only effect how much power it will take to keep up that cadence with that gear combination.


Cadence and speed monitor on rear wheel?

The Polar 200 user manual says that the speed sensor and the cycling computer must be no more than 30-40cm apart.

The cadence sensor attaches to the frame, near the pedals.

You could test how far away the speed sensor will transmit by just moving the computer away from the bike with the front wheel spinning. If it works at 1 meter distance, then putting the speed sensor magnet on the rear wheel and moving the sensor is worthwhile.

It could be that you'll need to juggle the orientation of the sensor and the computer to see how they work best.


Unfortunately, if the bead is popping out, you're going to need a new tire. Your tube could have a blow out through the gap. You may want to inspect your brakes and make sure they were not rubbing on the tire.  This could be causing pre-mature wear around the edge of the tire near the bead.


It's a spoke wrench.

Similar to this one:

http://www.btosports.com/p/bikemaster-spoke-wrench


I would suggest temperature change may be affecting the cable housing dimensions, which in turn affects the cable tension and therefore the dérailleur settings. I have been noticing this happening to myself this fall, especially switching to a bike with full length housing and 10 speeds on the rear dérailleur.  With the large daily temperature changes in fall I find myself adjusting the rear dérailleur tension by a quarter to half-a-turn in either direction depending on how the temperature has changed.  (Luckily the bike has inline adjusters near the bar, which makes this a trivial exercise).

Metal will expand or contract with temperature, and therefore the dimensions of the cable housing (which has metal strands) and the cable itself can change slightly with temperature changes.

For what its worth I never noticed this issue on older bikes with 9 speeds or lower (with or without full length housing).  I have however started noticing this issue with full length housing and higher speed drive train (i.e., 10, and 11 speed).

Solution/Hypothesis Test:

If you are handy at adjusting derailleurs, then you can test this hypothesis and potential fix the problem at the same time.  The next time the shifting problem emerges try adjusting the derailleur.

If it happens in the fog, you will likely have to add tension/elongate the housing by loosening the rear derailleur adjuster. If the shifting improves, then half the hypothesis has been verified (H1: cable housing contraction in colder weather).
If after (1) the weather warms up and the shifting goes off again, try tightening the rear derailleur adjuster (effectively shortening the cable housing).  If this fixes the shifting then consider the second half of hypothesis verified (H2: cable housing expansion in warmer weather).

Bike Geek Aside

As an aside, the expansion and contraction of the housing and cables will counter act each other to some degree (e.g., contracting housing will lessen cable tension, but contracting cable will increase tension).  Each component will also expand and contract at different rates.  My anecdotal experience seems to suggest the expansion and contraction of the cable housing has the biggest effect. Another big effect I have found was adjusting the cable tension inside, where it is warm, the riding it outside where it is cold would quickly throw all my setting off.


A 1mm curve on the brake track suggests that the rims are worn and you need new wheels; on the other hand, it's strange that they'd be so worn after only 1300km. I'm not sure how much that will affect your braking performance but the rims weaken as they're worn away by the brakes (of course) and will eventually fail if not replaced.


"Spinning" your legs as fast as they can go (i.e. pedalling at the highest cadence you are able to sustain), so going as fast as physically possible in the gear you are in.

Usually at that point you'd change up a gear to bring the cadence back down to a manageable level, but if you are already in your highest gear that's not possible so you're at the limit of what the combination of you and your bike's gearing can physically achieve.

When you reach this point you will often feel like you're bouncing in the saddle as you sacrifice pedal stroke quality in order to try and keep you legs spinning fast enough. It can also feel like you have less of a connection with the bike, and by extension the road, as you can't spin your legs fast enough to have any resistance / anything to push against - these two things combined can quickly lead to a lack of stability on the bike. You can see this in action in videos of "roller races" (literally racing on static rollers), where the resistance provided by the rollers is very low.

As an aside, the "Velominati" refer to the speed at which you "spin out" as Escape Velocity.


Swapping STIs for barends -- what issues are likely to arise?

The inimitable late Sheldon Brown left us a great post on shifters and gearing and compatibility.  The highlights for this kind of swap are:

For the bike getting the bar end shifters:

Likely no problem.  If the rear shifter is indexed but the indexing doesn't match the gearing then you can usually switch to 'friction' mode.  May be annoying if you are not used to friction shifting, but will be functional and you will get used to it in a ride or two.  You may even find that you like being able to 'trim' a shift like you can with friction shifters.
Bar End front shifters are usually friction anyway, so no problem there.
Cables will probably have to be rerouted and bar tape replaced.

For the bike getting the STI shifters

Gearing must match.  You will run
into trouble installing 9-speed STI
shifters on a bike with an 8-speed
cluster.  The derailleur will usually
work with multiple cog counts if it's
reasonably modern. The indexing/shift
distance is controlled by the index
gears inside the shifters.
Front shifters are indexed as well, and may only work with certain
chainring sizes/configurations.
Again you will probably be re-routing cables along the
handlebars and replacing bar tape.

Brake Levers

You can also run into issues swapping the brake levers.  Brakes differ in their 'pull length' so levers that work with center-pull cantilevers like I have on my touring bike won't work if I move them to my old beater mountain bike that uses direct-pull V-brakes.

Here again is Sheldon Brown on Cantilever Brakes - scroll down for the compatibility info.

Summary

If the cog counts are the same and the brake pull is compatible then I say go for it.

I like working on bikes, and live close to a bike shop so that if I need a part it's a quick jaunt. If the gear counts match for the bike this is exactly the kind of thing I would find 'fun' to tackle.


You need an offset chainring for this to work well. Otherwise the front chainline will wind up too far in, and when you're riding it with the small cog the chain angle will be extreme and likely problematic, i.e. as though you were crosschaining a double. There's a Wolf Tooth 28t x 64bcd ring that does this. (I'm assuming your frame is either 135 or 142x12; if it's Boost there's not a way for this to work reasonably.)

Presuming you're suggesting using the small ring off a double FC-M8000, that won't work because it's just a normal ring for derailleur use. In addition to not being offset and thereby putting the chainline too far in, it will want to cause rather than prevent derailment in the smaller back cogs when used without an FD in the way. There is zero reason to not use a proper NW ring.

Exactly how bad the results are if you go with a chainline that's too far in also depends on chainstay length and frame alignment.


Replacement for Suntour NCX-410 crankset on commuter bike?

Unless your bottom bracket is giving you issues, you shouldn't need to replace it.  Sealed cartridge bottom brackets have quite long lifespans.

The link you provided indicates that the current crank is designed for a 113mm long spindle (that's the LL113 bit), which is a fairly common size.  My personal favorite square-taper crankset with replacable rings is the Sugino XD-350, which is also designed for a 113mm spindle.  It's basically a drop-in replacement for the cranks you have now.


Can I use a Shimano XT 11-gear derailleur with a 10 ring cassette on a mountainbike?

10 and 11 speed systems are not compatible. The pull ratio of the shifters is different, as is the cog spacing of the clusters.

You may get away with some combinations of frankien-mixandmatch, but as the drive chain wears, the differences become more problematic. Ultimately, most find its not worth the problems it creates.


Cartridge wheel bearings - is there an inside/outside?

Among bike parts manufacturers, the norm by a very wide margin is for there not be sidedness. There are exceptions, such as hubs that use sealed cartridge angular contact bearings, but I believe those always have different color seals on each side, and there's not very many companies that use them. And there are some cases such as Campy freehubs where you remove one side's seal before installing it.

As I understand it, the seal (closure) type code you see on the seal of a bearing describes the type of sealing used by the closure it's inscribed on. I believe that in all cases, if it says the same thing on both sides, you don't have to worry about sidedness.


That looks like broken glass cut to me, you might find the remains of the sliver in the bottom of the cut. Over time that fragment will work inwards and eventually you will get a puncture.

That's left will be smaller than this, the sharp, flat edge that actually cut into your tyre then broke off:

This question has photos of a similar problem, where not getting the fragment out meant puncture after puncture. And this shows the punctures you get.

One maintenance task some people do is to get a sharp metal object and dig all the little splinters of glass out of their tyres. That does reduce the number of punctures, but in my experience it saves ten minutes of puncture repair for every hour or two of picking bits out of the tyre. It's not worth it. Instead I use puncture resistant tyres, which are heavier and slower than ones like yours. I probably spend an extra hour riding for every ten minutes of puncture fixing avoided... but I ride partly for fitness so that doesn't bother me.


Why are there almost no bikes with a single chainring?

1x9 setups are more common on a mountain bike or commuter bike setup with rapidfire shifters than a drop bar setup. However, due to a lack of front derailleur they can have chain jump issues due to the effect of the rear derailleur on the chainline.  This has to be compensated for, often with a chain guard on the outer side and jump stop on the inner side of the front chainring. It's also a bit weirder to have 2 STI brifters and only have one of them for shifting on a road / cross bike. Especially when brifters cost a lot of money.

Most groupsets come with all the drivetrain and shifting gear for a 2x9 or 2x10 setup. So, they install it on the bikes as a set, It would probably be cost prohibitive for manufacturers to break up the groupset and they would probably have to pay for extra parts (like a chain guard) to make it work.

There are however several bikes on the market with a single front chainring and an internally geared rear hub. These bikes don't suffer the downfalls of having to deal with chain jumps as much as bikes with derailleurs since the chainline stays consistent (and hopefully releativly straight).

UPDATE: Modern mountain bikes and some cyclocross bikes have been switching to 1x drivetrains as a standard drivetrain option. New technology, clutch rear derailleurs, narrow wide chainrings (there are several variations), and wider range rear cassettes (up to 44t) have made it so you can have a wider gear range and get rid of the extra chain retention gear that you used to need for this setup. SRAM and Shimano both sell 1x drivetrain groupsets and now some frame manufacturers are dropping support for front derailleurs.


How to increase the durability of gear-shifters

There are a few ways that user habits or mechanical adjustment can negatively effect durability:

If you downshift the right or upshift the left when the cranks aren't moving, you'll be putting excess force through the internal parts. A little bit of this isn't a big deal, but doing it habitually can break shifters.
Left shifters sometimes fail prematurely due to a combination of too much cable tension and the front derailleur high limit screw being set in enough that it causes the shifter to be held under tension when in the large chainring position. What happens then is that when shifting into the middle ring position, the release lever push is very hard and excess force is put through the shifter.
Some people shift more than others. This has an impact on shifter lifespan.
Shifters need their internal lubrication, and some environments are harder on it than others. Usually this would not explain the kinds of failure you're talking about, but sufficiently rainy/salty environments could prove an exception, especially if the bike is stored outside. Shimano trigger shifters are factory lubricated with a few strategically placed globs of highly washout resistant grease, which can be carefully replenished if things do get dry inside.
Some cyclists ram the shift levers with arbitrary amounts of force and others have shifting technique that's more calibrated to the fact that there are internal parts sliding past each other inside making it all work. The former will wear out shifters faster. Usually the difference will be fairly minor, but again it's conceivable for more extreme cases to prove an exception.

Shifters get more durable the further up in the product line hierarchies they are. Someone riding as much as you describe is generally speaking going to be the kind of cyclist that benefits from getting mid-range or better components, i.e. Deore. That said, all trigger style shifters could suffer and break from the above conditions, and I'd suspect there's some cause other than putting a lot of use through low-end shifters that's causing the failures.
The highest durability compatible indexing shifters you could get are Shimano SL-BS77 bar-ends mounted to something like Paul Thumbie mounts. The ball detent based indexing they use handles force in a very different manner than pawl type indexing, and they are more inured to some of the above problems. That doesn't mean that going that direction necessarily makes sense given the expense, or is the only solution.


Difference between Shimano HG51 8-Speed Cassette and Shimano HG50 8-Speed Cassette

The only difference is the model number, and the year of the design. They are fully compatible, assuming the number of gears is the same, and that you buy the appropriate match to your bike. The road version is Tiagra 8 speed. The mountain/hybrid version is Alivio 8 speed.


You are correct that the 42x26 is telling you that the large ring has 42 teeth (and the small 26).

I did a search on "M785 replacement chainring" and found a number of sources (but nothing a Chain Reaction). Looking at what I found it appears that the options for the large ring are 38 and 40 teeth. So…

Either Shimano has changed the specs on the M785 and the 42 tooth ring is no longer available, or there is s typo on the Cube site. I'd say it's worth looking at your bike to see if the tooth count is stamped on the chainring or, failing that, count the teeth.

If it is a 42 tooth ring (and you want the higher gears) it might be worth going to your LBS to see if they can order the 42 tooth ring, or else look for NOS (new old stock) rings on places like Ebay.


Help with choosing an entry level mountain bike

First of all, why do you want a mountain bike?:

  The nearby nature includes mostly 4X4 paths, sometime narrower but in general in such a paved manner.

This is definitely not what a mountain bike is for: They are intended for serious trail use, i.e. broken paths with lots of obstacles/debris. Given what you're describing and your beginning riding "style", I'd personally recommend either a lower-end touring or hybrid bike with tires more meant for off-road use: They will be more comfortable to ride for longer periods, will be easier/more enjoyable to ride fast (less rolling resistance) and can be easily used for stuff other than trail riding such as hauling groceries with a rack and panniers. Mountain bikes are a pain to use for anything other than, well, mountains†.

However, in order to get a new bike which you will really enjoy riding and can depend on for a long period of time without it breaking, you'll unfortunately have to spend a lot more than $350 USD (cf. a 2015 ranking of good entry-level mountain bikes, on which most start at around $500). Unfortunately, although bikes at e.g. Walmart may be in that price range, you will regret spending that much when just a few hundred more will get you a very respectable machine.

However, you can find a great deal on a used mid-range bike on sites such as craigslist: By buying used, you save the instant "drive it off the lot" depreciation which comes with a brand-new machine. If you don't know anyone who can help you find a good deal on a used bike, however (it's like buying a used car: be careful and always be ready to pay for repairs after buying it), many reputable LBSs will have a few used bikes for sale or will know someone who does.

† Although this recommendation is biased since this is my absolute favorite type of bike to ride, if you really are into doing mixed light off-road stuff like you describe, consider getting a so-called "adventure bike", which is basically a road bike for people who aren't afraid of getting dirty. These bikes are ridiculously fun to ride on nearly any surface and you can still carry groceries with them when needed.


can i get a new suspension kit for a older mongoose XR-75

This is a bso. You won't find replacement parts that aren't maintenance items (brakes, tires, tubes, freewheels, etc.), since they will exceed the cost of the bike (particularly big things, like suspension or wheels). The suspensions on these bikes are mainly for aesthetics, not for actually taking hits in mountain biking (full suspension bikes are jolly expensive; front suspension only bikes are not that much -- few hundred bucks to start for decent basics, cheaper on used market).

You're better off getting a new bike if you need suspension, or living with the suspension as is.


Connect a classic raleigh dynamo hub to a lamp?

Modern lights run on 6 volts. The front light is 2.4 watts and the rear is 0.6 for a total generator output of 3.0 watts. The first thing to do would be to see if you have one wire connection or two. If you've only got one then the dynamo is probably built to use the frame of the bicycle as ground. If there are two then one is the hot wire and the other is ground. With older, halogen, bulbs the polarity (which wire on the dynamo you hook to which wire on the light) doesn't matter. Modern LED lights may care, so use a meter to figure out which wire is which – you may also be able to tell by looking carefully. The ground, or negative, wire is usually marked in some fashion. Typical markings are a white stripe or a ridge on the wire.

After sorting out the connections, you need to know the voltage. See if you can find a readable rating on the dynamo, or failing that put a meter on the outputs and spin the wheel – the voltage will probably vary with speed, but it shouldn't be too hard to tell if you're getting something close to 6 volts at normal speeds.

If you have 6 volts then you should be able to hook up a modern light. Just connect the wires (if there are two), paying attention to the polarity. If there is only one wire connect the positive from the light to it and the negative to the frame of the bicycle. If you connect a light and nothing happens, try reversing the wires it may be that you have the polarity backwards.

If the output of the dynamo is more than 6 volts, you have a different problem. Too high a voltage will damage the light. So if the voltage seems too high, start by connecting a light that works and spinning the wheel at a slow speed with a volt meter attached. Watch the meter as you spin the wheel. Sometimes a load on the generator will bring down the output voltage. Again at normal riding speed the dynamo output should be right around 6 volts.


Spoke tension - is a left tilt ok to prevent explosion?

Your wheel is overtensioned. That is not good as it will eventually lead to premature failure somewhere, maybe worse than you're currently experiencing.
In the case of wheels that don't come as manufacturers' sets, ie the spokes, hubs, and rims were all purchased separately, the spoke and the rim and even the hub are going to have different maximum tensions. In this case if you overtension the rim it will either not stay true or crack at the spoke holes- in extreme cases it can even encourage the wheel to taco under less lateral load. If the spokes are overtensioned they will eventually snap. Should the hub have the lowest maximum tension and you overtension it you run the risk of breaking the hub flange.
In the case where the wheel comes as a manufacturer's set (for example, many high end Mavic and Shimano wheelsets have compoenents that are all proprietary and only work with a given wheelset), you're going to have a maximum tension which is still going to be limited by one of the aforementioned components but you likely wont know which one. Same rules apply though- something will prematurely fail if you keep the wheel overtensioned.
You need to let the tension down instead of bringing it up to get the dish correct. How old are your wheels? If they're relatively new you may have a warranty issue on your hand, although you may have voided said warranty by overtensioning the wheel. If the wheels are old, it's important that spokes have a fatigue life just like everything else and you may be hitting it. Often when you get close to the fatigue life of the spokes on your wheel you'll bust one after another until you relace the wheel.


Can I put 700c tires on rims made for 27 x 1.25"?

No!!!

I tried this when I was knee-high to a grasshopper and it so-did-not-work! I actually managed to get a Michelin Select 700 x 28c tyre on the 27" wheel but the inner-tube was so pinched and pierced that no amount of that gunk you can spray into tubes could save it. I did get the size wrong but after many hours of struggle 'hoped' to get a low-profile tyre on my front wheel.

The bead diameter of the 27 inch wheel is 630 mm, the bead diameter of a 700c is 622 mm (I properly learned those measurements that day). 8mm is a big difference, believe me!

If your LBS does stock 27" tyres, do not part with your cash until you have read 630 on the sidewall. If they do not stock them, ask them to get them in. This will save you the postage of mail order. Their suppliers will carry them and they should be able to get them in for next week if you ask nicely and put down a deposit.

There are specifications for wheel sizes and tyre sizes - ETRTO. Schwalbe have a good intro and list of sizes:

http://www.schwalbetires.com/tech_info/size_markings

The 27" size for your bike will be 630, 609 is the size for older bikes with 'rod' brakes and no sidewalls to the rim.

Normal 700c inner tubes will go in a 27" wheel with no problems.


Changed shifters and chain isn't in same spot

This happens everytime one replaces a component of the drivetrain since the original cable position is rarely restored.
He needs to do something called indexing the gears. It is a common procedure and there are many good tutorials online explaining how to do it much better than I could. Here is one I'd trust-


If you have disc brakes you can use zip ties to create a cheap studded tire and can remove the zip ties when you're done. Get long enough zip ties to go around your tire and rim. Because of this, it will not work with rim based brakes.


Chemically roughening rim braking surface to improve performance

When I was into freestyle BMX in the early 2000s, we had a few tricks to improve braking. Much of the tricks were designed, like in the case of trials, toward having brakes that can be locked up solid with the least amount of effort so that you can consistently lock them up with 1 finger. So modulation was not usually a goal.
First of all, contrary to the trials example provided, we did not find that rougher rims were better. The friction characteristics of rubber on rims is complicated, and apparently making the rims rougher can also reduce the surface area in contact with the pads, and may also scrub the pads away faster. But whatever the reason, and while I'm not doubting the trials technique could work, I'm just saying that we didn't find that rougher rims were better. In fact, usually rough rims got better after they had worn smooth, and for people to find that their brakes actually got worse after sanding the rims. And it was widely believed that chrome-plated rims, which were nearly mirror-smooth, were the best of all for braking.
About applying substances, the usual suggestions were Simple Green or Coke. In my experience both worked, but Coke didn't last very long, and both usually caused squealing during non-lockup braking.
Some household cleaners contain lye, which will etch aluminum and remove anodizing. One example is Purple Power. If you are looking for a substance to experiment with, lye seems as good as any (although it can be dangerous), but I have no experience with using it to improve braking. Most all my bikes have disc brakes.


Are deore 9 speed shifters compatible with Alivio & Altus derailleurs?

Yes. You can take any 7-9 speed Shimano rear derailleur and use it with any Shimano 7-9 rear shifter. And the Deore front shifter will pair fine with the Altus FD.


Is a Racing-Bike making creaking noises a sign of equipment damage?

I'm not gonna ding you with a "duplicate question", but see, eg, Creaking from cranks/spindle. How to fix? .  And there are several others.

Creaking is a fairly common problem and can be due to a number of causes:

The crank arms shifting on the crank axle. (This is by far the most serious of the conditions, since, left untreated, it can result in expensive damage.)
The pedal threads creaking in the crank arms.
The bottom bracket cartridge shifting between the cups.  (Though this is more apt to make ticking or "ping!" noises than creaks.)
The handlebar.  With lightweight bars there is a short tube-like stiffener glued over the center portion of the bar, to create a more robust mounting point for the stem clamp.  The bar proper can shift in the tube and creak.
Wheels/spokes.  Very often "crossed" spokes will creak or go "ting" where they cross.
Seat/saddle.  Springs may creak, or any of several parts may move relative to each other.
Frame.  This is rare for a steel or aluminum frame, but may be more common with carbon.  Generally creaking from a steel frame would suggest imminent failure, but it's harder to say about the others.
The rider.  I know I creak more and more as I get older.  (And I actually do have a trick ankle that will audibly "tick" at times when I walk (loud enough for others to hear), though generally not when I'm riding.)
Stem in the headset.  If there is some play/looseness in the stem's insertion in a threaded headset, then the shifting weight/pull/push on the handlebars can cause vibrations that make it creak.

Other than the frame and the crank arms, creaking is generally not a serious concern.  But it can drive you crazy.


When Mark Cavendish says he's sprints at 1500 watts how long is that for?

That kind of power is going to be between 5-30 seconds, and is most likely a 5 second maximum, or he's quoting the absolute peak that he put out.

There is a very interesting analysis of several Team Columbia riders from a couple years ago when Cavendish won the stage. A few riders have 30-40 second pulls at the front in the 650-700 watt range, and in the leadout, Markus is at 700+ watts for over 30 seconds with a peak over 1000.

So if the leadout is at 1000, Cavendish probably is doing 5-20 seconds in the 1200 range as he comes around the slingshot, with surge peaks into the 1400 range, but that level is not sustainable. You can see this when sprinters mistime their sprints and start losing steam short of the line.

Here is the link with the powerfiles.


No I've not used those specific ones.  However I have used spoke-mounted clip-on reflectors, and consider them far superior to the traditional yellow plastic blobs that adorn many new bikes.

Reflectors on the wheel make your bike much more visible from the side.  Lights are generally not set up to point sideways, and they have relatively little leakage to the sides.

Reflective sidewall tyres are okay, but they're a continuous band and don't have the same movement that revolving spoke protectors have.

Answer:  Sound concept and good idea

Pricing?  That is for you to decide and we don't really do prices here because the website is global.  On looking at the website, they seem to be stickers made of reflective material, similar to whats on a roadcone.  Your local craft shop or safety department in a hardware shop probably has rolls of similar reflector tape.


Sheldon Brown has a thorough article about stuck seat posts. http://sheldonbrown.com/stuck-seatposts.html

Thick soled shoes might also work, if the saddle isn't that much too high.


Purpose of this hinge component found on the pinch-bolt of front brake?

The lever pointed down is in the closed position and is how the manufacturer intended for the brakes to be used. The brake pad clearance should be set in this position. If the brake cable is routed correctly and the lever fully closed (and not damaged), tension on the brake cable will further lock the mechanism in place as it is on a slight angle causing the lever to be further pulled closed under braking tension.

The lever in the up position opens the caliper arms up wider to facilitate wheel changes.

Some people flip up the lever as a lazy way to get extra brake pad clearance when the rim gets out of true, but it isn't the best idea. That said, the brakes will still work, but are generally less effective with the lever positioned up.


Ultimate way to communicate while riding, an offline walkie talkie app?

Have you tried talking with the people you ride with? If traffic is too noisy to understand each other, look for different routes. What is more, such busy traffic is not the time and place for chit-chat.

On a moderately quiet road I find it easy, and pleasant, to chat while riding side by side.

When riding in a file yelling and gestures work well. If you go on a group ride it might be a good idea to agree on some useful phrases. Select them in such a way that similar phrases sound distinctive.

There are a few hand signs you may want to learn. Typically one uses the hand towards the centre of the road to indicate. Most symbols are displayed low, just beside one's buttocks.

Stop:
Flat hand up with bent elbow (not in USA, might indicate turn)
Hand down, palm facing rear.

Pot hole, obstacle:
Finger points, down, at line that leads into the hole.

Slow:
Flat hand with palm facing down, wrist extended, elbow angled, hand and lower arm parallel to ground, move hand slowly up and down.

Here's a video explaining some symbols:


The make is Apollo and the model seems to be called Sand Storm.

It’s a (full suspension) mountain bike style bike, although it isn’t really strong enough to ride off-road much. Probably great fun for riding to and from school though.

I’m not sure what you would put for “Frame of bike” as it seems synonymous with “Type of bike” unless you need to know the frame number, which is likely to be found under the bottom bracket, the part of frame between the pedals.


You should not be getting multiple flat tires in such a short timespan. I commute on poorly-maintained roads in Atlanta, and have not had a flat tire in 4,000 miles.

In order of estimated likelihood, either:

your tires are not properly inflated
your tires are worn or punctured and need to be replaced
you have a sharp object embedded on the inside of your tire
you are exceedingly unlucky

If you've just started cycling again, I think it's exceedingly probable that you've simply neglected to inflate your tires to their recommended pressure. Standard road tires should be inflated to pressures of 100PSI and beyond. Mountain bike tires (which are awful for road use, but I digress...) require much less. It's easy to grossly underestimate how much to inflate a bike tire, and a standard hand pump will likely only get you to 30-60 PSI before you give up.

Take your bicycle to your nearest bike shop and have them examine the situation. Flat tires should not be a common occurrence.


The answer is not really. Chains are dirty and they get you dirty.

Dry lubes tend to be better than wet lubes in this regard, but they'll both quickly get your legs dirty. But dry lubes are normally not considered to be good for wet riding.

You can clean your chain periodically (e.g. Park Tool CM-5.2 Cyclone (TM) Chain Scrubber, which clamps onto the low tension part of the chain, runs the chain through a pool of cleaner with some foam and bristles to scrub it as you back pedal), and relube it, but the crud from road and stuff will make any lube dirty quite quickly. Some more elaborate and thorough ways of cleaning a chain (with considerably more work) are outlined here.

The other options are chain guards or full chain cases (possible with an IGH if you need gears) or belt drive. And tying your pant legs helps a good amount too.

Edit: I've added some notes on chain cleaners from some chain manufacturers (Shimano, KMC, SRAM). Follow at your own desire. Many people use chain cleaning machines like the Park Tool CM-5.2 or remove their chains and soak them in a solvent for a bit, but manufacturers are generally against this. YMMV. FWIW, I own a CM-5.2, but I don't use it very often.

KMC does not recommend the use of a chain cleaner like the Park Tool CM-5.2 (in the CG-2.2 kit):

  Clean your chain after every ride, especially after riding in the wet.

  Always use a piece of dry cloth to clean the chain.

  Do not forget the sprockets, front changer and derailleur pulleys.

  To remove mud or sand, use the bristle brush (which comes with every 120ml packing of KMC’s chain lube Pro), use light soapy warm water, if necessary.

  Do not use acidic or alkali based detergents (such as rust cleaners), these can damage the chain and may cause breakage.

  Do not dip your chain in (aggressive) degreasers - they remove the remaining grease from the chain’s bearings, and may cause cracks. They are also bad for our environment.

  If the chain is really dirty and difficult to clean, besides using a brush for the inside, try putting some solvent on a cloth and use it to clean the chain’s exterior.

  Try to avoid a so-called ‘chain washing machine’ in combination with solvent. This will instantly ruin your chain.

  Some lubricant brands advise you to completely degrease the chain, KMC does not recommend this.

Shimano recommends wiping the chain with degreaser.

  In dusty conditions you can wipe off the outside of the new chain with a rag that is wet with a gentle degreaser to keep dirt from sticking to the grease.
  and
  Maintenance interval depends on the usage and riding
  circumstances. Clean regularly the chain with an
  appropriate chaincleaner. Never use alkali based or acid
  based solvents such as rust cleaners. If those solvent
  be used chain might break and cause serious injury.

  You should periodically wash the chainrings/sprockets in a neutral
  detergent and then lubricate them again. In addition, cleaning the chain
  with neutral detergent and lubricating it can be an effective way of
  extending the useful life of the chainrings/sprockets and the chain.

(From Shimano SI-09R0A-002-00)

From SRAM Technical Manual 2010:

  Clean dirty chains before oiling. Do not use any acidic agents. Cleaning agent must be rinsed off after a few minutes with water. Apply oil after chian is completely dried.

  Regular lubrication will extend the chain's service life. Apply oil to the chain links rollers and allow to work in.


If you are an adult, I would say that you will be more comfortable using a 24 or 26" wheel versus the 20" wheel which is mainly for trick riding.  Especially if you want to commute a bit the larger wheel will come in handy. Once you are comfortable on a 24 or 26" wheel, you may want to graduate to a Coker or big wheel cycle for getting around fast (I can average 12 to 13 mph for over 20 miles) Go to unicycle.com and look under commuters and you will find some really nice cycles.  I used to ride a 42" Tom Miller big wheel from The Unicycle Factory and switched about 10 years ago to a 36" pneumatic tire Coker.  I have made many modifications over they years so that now the only Coker item left is the tire but it's a great cycle.  I hope this helps.


Looking at the integrated shaft and the style of bike it could be from Arcade. I can't see the bike in their current catalogue, but that's hardly surprising. Maybe if you contacted them directly they could help you out.

This is the key part of the only shaft drive bike in their 2016 range:


Most carbon rim manufacturers like zipp and enve recommend a brake pad of their own.  However, there are typically several pads that will work.  Most of these pads are designed specifically to work well on carbon rims. Regular brake pads from alloy rims should not be used on carbon.

Zipp recommends the following pads for their rims:
Zipp Tangente Platinum Pro
Zipp Tangente cork pads
Bontrager cork pads
Zipp carbon/carbon pads
SwissStop yellow pads

So, I would check with the manufacturer of your rims to see what pads they recommend and stick with those, otherwise you could be voiding your warranty on an expensive set of rims.

Leonard Zinn (author of Zinn and the Art of Road Bike Maintinance and owner of Zinn Cycles) recommends against using regular pads on carbon rims.  See the following from the article in velonews:

  I can say from personal experience that standard brake pads on
  carbon rims are grabbier, giving louder, less predictable, potentially
  dangerous braking, and they wear faster, even melting down rapidly at a
  critical moment on a long, fast, tortuous descent, leaving you with no
  brakes at all. Furthermore, conventional pads on carbon rims are
  down right scary in the rain, making for unpredictable braking until the
  rim is wiped clear of water enough for them to grab.


Looking for cleats to match my vintage Mavic pedals

I don't think those are the 646, but the cleat you probably still want to use is the Look Delta cleat. Go to a bike shop and try the delta cleat in there.

In the olden days, everyone was rebadging Look cleats as their own.
The 646 (and many old pedals) use Look Delta cleats (aka the original/traditional/ARC Look cleat; NOT the Keo cleat). The 646 should use the black cleat since it has float adjustment on it.

Picture of the Delta cleat (From REI):


There's a good article here which explains it pretty well - although there are 21 gears there are only effectively about 11 distinct useful gears on a typical 3x7 gear setup:

That is to say, some of the gear combinations overlap (or near enough) and this means you don't really get any extra function from them, but having them can make gear changing up/down a range smoother because it means you have to change the front sprocket less often. The exact number of "useful" gears will change based on the number of teeth you have in your particular setup, but the principle is the same.

As you can see from the graph, you do gain extra range from having an extra front sprocket - if you only had 28t on the front then adding a 38t gear gives you 3 extra useful gears, then adding a 48t gear gives you another 2 on top of that. This is good but it's not really the same as adding an extra 7 useful gears each time.

Also as some others have mentioned, gears don't always come in multiples of 7, this just seems to be the most common number of gears in the rear cassette of most mass-market bikes.


Difference between a 7 speed chain and a 10 speed chain

Yes, while the internal width is the same, the external width of 10 speed chains is narrower.   Refer https://www.parktool.com/blog/repair-help/chain-compatibility


What's the purpose of the Weeride Copilot "safety" tabs?

I think the only real reason why you shouldn't remove them is that if you're moving the whole thing (without anyone on it) and it violently crashes against itself (say you pick it up to store it and it slips) then the safetly tabs will take the damaage and potentially save the rest of it.

Apart from a case like that, if you're safe with how you use it, the safety tabs can be removed.


The main problem I see with Gates Carbon Drive on a fat bike is that you have to have a frame that "breaks" in the rear triangle to accommodate threading the belt. Have you checked to make sure there's a frame available that supports fat bike tires and also supports breaking the chainstays. As far as off-roading goes, that would create a potential weak spot in the frame. Although I"m sure any quality bike manufacturer would account for that when building such a frame.


Ferrule size for a road brake cable housing slot?

Many road calipers don't have you use a ferrule at the brake end. That's the intent here. If you want to anyway or if you must due to using a braided/compressionless brake housing, the solution is to use stepped ferrules such as Jagwire POP ferrules, which are long and have an opening for 5mm housing on one end and reduce back down to 5mm OD on the other end.


How much slower should I expect to be in winter rides?

This source goes into quite a bite of detail on the subject.
The three main reasons they go into are higher air resistance in the cold because cold air is more dense.  Increased rolling resistance as cold tires cannot deform as much as warm ones. They also mention the bulkier clothing causing more air resistance.
One advantage of colder weather is that you are less likely to overheat. This can increase performance.  I have felt this effect of being able to maintain my efforts longer on cool fall days, while cycling on my trainer is often more difficult as there is no air flow to carry the heat away.  Also, cycling on hot summer days can also be exhausting.
Just be careful not to overdress for the cold as having too many layers could also  make you overheat. It's ok to start off cold as you will warm up during the ride.


How can I use a small Shimano BB on any frame?

The link says that the BB you have is a 68mm shell width, which is standard ISO/British thread.  That's going to fit a lot of bikes.  It is not designed specifically for eccentric bottom brackets.  To use the item you linked to in a single/fixed speed bike you would need horizontal (or at least diagonal) dropouts.

If that was part of an eccentric BB assembly, you would also have had something sort of like this:

http://www.jensonusa.com/Misc-Frame-Sup-Bushnell-Eccentric-BB

that it would have gone into, and then that eccentric BB would have gone into an oversized/eccentric bottom bracket shell that was part of the bike frame.

If you still have that eccentric bottom bracket, then you might be able to go looking for a frame with a same-size eccentric bottom bracket shell that it would fit into.  Such a frame would then have vertical dropouts, because there's no reason to have an eccentric shell and horizontal dropouts in the same frame -- don't need to solve the chain-tensioning problem twice.


There are two things I generally do to help eliminate most of the twist.

When tightening spokes, get in the habit of slightly overturning and then turning back. (i.e. If I want to tighten a spoke 1/2 turn, I'll do 3/4 and 1/4 back. )
At regular intervals once the wheel is "close", take the wheel out of the stand
and place the wheel vertically on a soft surface like a piece of carpet or wood.
Lean your full body weight on the on the top of the rim. Turn the wheel slightly and repeat until you've done at least one revolution of the wheel. This simulates the load the wheel will encounter during the first ride. You should hear the same kind of pings. It's important that whatever you put the wheel on is softer than the rim material, you don't want to put any dings or dents in the rim.

Neither of these techniques is perfect, most wheels I've built require a bit of initial tweaking after the first week or so. But they will get you much closer.


How do I determine my bike's fork width?

This refers to the interior distance between the rear wheel dropouts on the frame. The rear triangle is sometimes referred to as the frame 'fork', not to be confused with the front wheel fork.

The vast majority of modern bikes with quick release hubs have 100mm spaced front wheel dropouts and either 130 or 135mm rear wheel dropouts. If you measure the distance with the wheel out it may be a few mm off of 130 or 135mm as frames flex a bit when the quick release is undone.


Sandpaper is overkill unless it's a very fine grit.  A wire brush would work but it's cumbersome to use on a round shape like that.  Steel wool is perfect.


A rear derailleur moves two ways: the tension from the shifter cable will pull it one way (usually towards the larger rear cogs) and spring tension within the derailleur will pull it back when you shift down into the smaller cogs.

It sounds like the spring tension is not strong enough to overcome the cable tension / resistance when you're shifting.

If you had to replace other rusty parts, you can try oiling or just replacing the derailleur cable and housing.  If those are rusty or sticky, then your derailleur spring has to pull a lot harder to get things to move.

I have also had shifting troubles when the derailleur hanger is bent, causing the mechanism to swing the wrong way when I was shifting.  You can get a bike shop to check / straighten the hanger, or if you don't have a hanger (claw type derailleur) you can try to do it yourself.


Can I put the speedometer sensor for my cycle computer on my rear brake line?

I have had a similar problem and solved it by using a small piece of foam pipe insulation. I see no reason why a piece of sponge or similar material wouldn't work. I used two zip ties to hold the spacer in place, then positioned the sensor pick-up.


How to calculate width of 28" tire to 26" with constant damping factor?

From my experience, dampening depends too much on non-dimensional factors. That makes very difficult to come with a formula that would work reliably.

Of course the width of the tire is a very important factor, and balloon tires always will dampen better than skinny ones.

But the hardness of the carcass (be it the layers within or even the rubber hardness itself, or the thread pattern) plays such an important role that I think it counts more than the difference in diameter from 26 to 28 inch wheel sizes.

I have ridden wide tires which were very bumpy and uncomfortable, and narrow ones that just made the harshness of the road disappear.

Also, and this might help to formulate a real answer to your question, are you referring to the transversal dampening, where the tire's cross section counts a lot, or to the longitudinal dampening, where the wheel diameter counts more - and which is responsible for "rolling over" obstacles being smoother on bigger wheels - ?


Coaster brake heat management and lubrication

Most people who aren't using a manufacturer grease are using a high temp automotive grease. I'd suggest looking at the manufacturer's recommendations and following them; brakes aren't a place to save a few bucks. 220 C seems low for the type of grease; people have failures with high temp automotive greases which often rated for 100 C+ higher than that on tough descents.
Brake fade, loss of braking. Brake might be smoking and ruined. Loss of grease and dropping of the grease is the least of your problems at that point given the fact that you're probably in for a not so nice crash.
You need to give the brake adequate time to cool off. This means controlling your speed by modulating your brakes (use in controlled bursts). You should also have 2+ independent brake systems which you can alternate with. If you use continuous braking over a long descent, you're just going to build up heat and have brake fade. Unfortunately, coaster brakes are prone to this in long descents making them not ideal; my advice is not to take a coaster brake bike on long descents. All brake systems will fail if overused.
Pretty damn hot ; an old article but probably still quite relevant. You normally only see coaster brakes on kids bikes and bikes which are used in low load leisure systems (e.g. beach cruisers), where this would not be a problem (not going very fast, not braking very hard for prolonged periods of time).  See (1). Measuring this on the surface of the hub wouldn't be too hard (thermal camera), but internally, you'd need some work.


General answer to: 'Do I have to be more aware of what I am eating or is it just fine for me to eat whatever I want...?' I'm pretty sure a doctor or nutritionist would tell you that you should eat a balanced diet, not one that is high in calories sugar and fat. I'm also sure a lot of people in this community will tell you that diet gets more important an you get older and a more sedentary lifestyle is forced on you (sitting at a desk 8+ hours a day).

If you are only doing two 5km rides a day you don't need a special diet - just a reasonably healthy one will be fine.


It's pretty easy if you have a spoke cutter and are willing to run a funny spoke pattern. I suggest buying (ideally second hand) a three speed hub and lacing it into the 16" rim yourself. With a wheel that small and a child on it there's not enough load to make strength an issue, so you can reasonably either lace a 20 spoke rim to a 36 spoke hub using whatever holes are closest, or ignore two spoke holes in the rim and use every second hole in the hub (18/36). It's probably not going to be pretty, but it will work.

However I think you're going about this backwards. Why are you riding faster than he can? Much as you wouldn't suggest stilts so he can keep up when you walk, gears don't address the problem that you can ride faster than him. He doesn't have the power or endurance you do, so without a power assist he's going to be slower.

If you need to cover long distances, perhaps a trailer bike would be a better solution? That way he can "help", and you can go whatever speed you like. That's generally safer for your kids, since you're in control and the only real risk is them jumping off the bike while you're moving.


Are deep V wheels only for fixed gear bikes?

Deep-sectioned rims -- particularly Velocity Deep Vs -- became popular among fixed gear riders because they came in a variety of colors (bling) and the larger section made that bling all the more prominent.

However, deep-sectioned rims have many applications beyond urban fixed gear bikes. They're typically heavier and don't do well in cross winds, but in straight-ahead road riding, they are thought to be more aerodynamic.

As long as the rims come with machined sidewalls, they'll work fine for your purposes. The machining greatly improves braking by making the contact point for the brake pads more consistent.

All that said, if you're riding around town or even doing more recreational road riding, I think you'll be better served by a smaller sectioned rim like the Velocity Aerohead.


How important is it to re-space my rear hub?

No, that much of a spacing difference is generally a bad idea even with steel because of the increased stress it causes in the dropout area, which may cause or contribute to failure of the frame in the dropout area over time.

How bad it is exactly on a given frame is difficult to pin down. But it's observably true that the right rear dropout is a common failure point from fatigue on heavily ridden bikes where everything else is holding up well. The static stress that gets created from having the frame squeezed down can only add to that.

Presuming it's steel, just respace it to 120, and then re-align the dropouts afterward. A side benefit is that you get to align the rear end at the same time you respace it, so it can be perfect on both fronts.

Having the spacing and dropout alignment be right will also make tensioning the chain during wheel re-installation be a much smoother process.


Derailleur Configuration - Anyone ever seen something like this?

I Designed wire and cable machines for about 10-years and a previous life and have indeed seen your setup many times as a system for maintaining tension on a cable; For that purpose it works great. If all you were trying to do was maintain chain tension at varying lengths, you would have something.

But as Carel points out in the comments (and I've spent years testing this), You absolutely want the application pulley/gear to be as near the point of application as possible. Failing to do so will guarantee that your chain will walk up and down the cogs at will and will not shift when asked to.

Your design would have to be modified such that the fixed pulley nearest the rear cogs would move in/out and forward/back as the gears change. Once you do that, you have something that looks very much like a modern derailleur (funny how that works).

The truth is that a derailleur is a pretty elegant and simple approach that has been tested, proven, and improved over many years. Your best bet, in my opinion, is to play with the placement of a derailleur so that it is less in the way.


How to fix this saddle for my road bike?

I think you have a mixup somewhere.  Those bolts look wrong - given there's a clearance hole in one cylinder and a threaded hole in the other, one bolt should pass through the first and thread into the second.
    +-+   +-+
[]===========>
    +-+   +-+
   slip   threaded

As yours is pictured, the two bolts would push the ends of the clamp apart, if they could both get a grip.
Look around for the missing bolt.   Those two look like water bottle cage bolts, or possibly stem bolts.  What else did you take apart that may have become mixed ?


Ouch, I'm really sore. Should I take a break for a while? How long?

First off, if the soreness is such that you feel painful stabs when you move/stretch the muscles you definitely should rest for awhile (at least several days, maybe up to 6 weeks), and perhaps should see a doc.  This can be a sign of tendinitis, muscle pulls, or a muscle disorder, and continuing to exercise in such conditions can lead to permanent damage.

General soreness/stiffness, on the other hand, is believed to be caused by microscopic muscle injuries that, as they heal, tend to strengthen the muscles.  For such discomfort you need to take is easy for a day or two, until the soreness/stiffness abates.  However, moderate exercise (well below your max effort) to keep yourself limber is often advised.


What type of tires can prevent goatheads?

I haven't tried them specifically with goatheads, but I've run through nails, staples, glass and just about anything else you could find in an urban environment on Schwalbe Marathon Plus ("flat-less") tires.

I have never had a flat over thousands of miles with their Marathon Supremes, either--and they're much lighter and better riding--but they're not as puncture-proof as the Marathon Plus tires.

Neither I, nor anyone in the group of hundreds of cyclists on a local Seattle mailing list have ever seen anything more puncture proof than the Marathon Plus tires.

Marathon Plus on Schwalbe's main site

Product listing from Schwalbe North America (distributor for North America).

They're available in a wide range of sizes.


There are two measurements, given as pitch x width. The pitch is the distance between rollers and width is the width that the sprockets have to fit through. The pitch is generally 1/2" on modern chains, but some old bicycles (esp. old track bicycles) use 1" pitch chains (skip link or block chains).

The width changes depending on number of speeds (so you'll have a lower width for higher number of speeds). So single speeds will often use 1/8" (some have sprockets designed for 3/32" though, so you should check), 8 speed will use 3/32" , higher number of speeds will use 11/128" (11 speed), etc. [possibly different between manufacturers].


In my experience, when a Schrader valve starts leaking suddenly, the most common reason is that there is a small piece of debris that prevents the valve from closing. The easiest way to remove them is to slightly overinflate the tire, then fully open the valve by pressing the center pin. If this does not help, the valve might be faulty and the tube should be replaced.


The grease on a coil spring is purely to reduce friction between the spring and the fork leg/stanchion. The choice of grease is non-critical beyond ensuring that it is compatible with the existing grease (or you clean the fork thoroughly to remove the old grease) and that it will not damage the seals. Natural rubber seals can be damaged by petroleum based greases however most fork manufacturers appear happy to use petroleum based calcium greases such as Buzzy's Slick Honey so this does not appear to be of much concern in practice.

The 2006 Marchozzi product manual does not mention or recommend a specific grease type. The closest thing I could find to a recommendation was a 2012 video of a Marchozzi employee rebuilding a fork with a similar design where around 17:40 he uses an amber coloured grease (likely calcium grease) to lubricate the dust seals. While there was no clear shot of the product used and no specific grease type mentioned, the recommendation was to use "lightweight low-friction grease".

Following that recommendation you would be safe using most types of general-purpose grease including castor oil based greases (as they will not degrade rubber seals), silicone or teflon grease (also safe to use with rubber), lithium grease, graphite grease, or calcium grease. Greases designed for high temperature/high pressure situations (such as automotive bearing grease) will not be as effective at lubricating a fork spring under typical use so should be avoided unless that is all that is available.


The brakes should be adjusted. The disc caliper mounting bolts allow a small amount of adjustment to center the pads between the disc rotor. Your caliper is likely misaligned allowing the rotor to rub on the pads. If the rubbing sound is cyclic meaning it rubs then stop at the same place each wheel rotation the cause is more likely a warped rotor. Another potential issue is the axle not fully seated in the dropout resulting in a slight misalignment.


This maybe late but KMC now manufacture a 1/2" X 1/8" splined sprocket for Rohloff hubs https://www.kmcchain.eu/webshop-sprocket

With a matching 1/8" chainring you can now use a 1/8" chain no problem.


please help me identify this bike, it is a haro bmx frame and i have the serial number

it should be a 2001-ish Revo because it starts with RV. This website may help:

http://bmxmuseum.com/forums/viewtopic.php?id=206889


Shimano FC-RS500 11 speed chainset with 10 speed cassette and chain

If you are using shifters that match the derailleurs (i.e 105 5700 series), then yes this will work.

11 speed cranks have a slightly closer chainring spacing than 10 speed to accommodate the narrower chain. Consensus on this site is that you can go one speed difference on the crank and get working front shifting.

I like to point out that the non-series RS500 cranks are somewhat heavier than 105 5700 and I would not call them a great match, but if you are looking for a way to get an affordable compact 110mm BCD crank to work with the rest of the drivetrain it will provide a workable solution.


Rear brakes wear quickly - do I need redundant rear brakes?

The system you suggest has no benefit. The effectiveness of the rear brake is limited by the fact that braking moves your weight forwards and off the rear wheel. The brake you already have should already be capable of skidding your rear wheel. This tells you that the limiting factor isn't the power of the rear brake, but the grip of the rear tyre. Making the rear brake more powerful won't make you stop faster: it just makes you skid sooner. And bear in mind that skidding is not the fastest way to stop – that (and keeping control) is why cars have anti-lock brakes.

Instead, you need to practise using the brakes properly. If pulling the front brake sends you over the handlebars, you're pulling it too hard. Brakes are not binary: they're not just "on" or "off". Learn how much front brake you can use without endangering yourself (practise on a quiet street at gradually increasing speeds) and remember to brace against the handlebars as you brake so your weight doesn't flop forwards.


I'm looking for a chainring compatible with bb86

I'm not sure about a list of chainring compatibilities.
I had a similar issue when I wanted to upgrade my drivetrain. My BB30 wasn't compatible with the DA9000 crankset, so I had to buy an adapter. Shimano makes an adapter for the BB86 if you'd like to buy a new crank based power meter, however, it may be worth investing in a pedal or hub based power meter instead as drivetrain changes can be finicky. As a side note, I've never had any problems with my BB30 Adapter and I've been running it for a little under a year. Good luck!


My tip would be don't disassemble the lever! Shimano unfortunately did not design their shifters to be serviceable.
Shimano STI levers had a terrible habit of fraying the cable at the cable head until it eventually broke off. This was supposed to be remedied in the new generation of shifters but they still do it to a lesser degree. In other words, you're not alone in this problem.
Unless you broke something while fishing the cable head out I'd say there's good chance that there's still a piece of cable floating around inside the shifter somewhere. My suggestion would be to undo the brake cable so you can pull the lever further back and get a powerful flashlight to look around inside the shifter with. Actuate the shifter and see if you see anything amiss. The whole thing would be easier if you take the shifter completely off the bike.


KMC X9 chain: can I replace some links from any chain?

A basic 9-speed chain doesn't cost all that much so in most cases this wouldn't be worth it, especially since having several damaged links kind of implies a chain that's pretty beat up and in imminent need of replacement anyway.

But, you can do it safely if you want to. A good approach here would be to take advantage of the fact that 9-speed KMC MissingLinks are designed to be fully compatible with both Shimano and KMC 9-speed chains, which implicitly means KMC designed their 9-speed inner link thickness to exactly match Shimano. So if you're replacing a damaged segment, get a scrap of any KMC or Shimano 9-speed chain, trim it so that it's got an inner link on both ends, and use 9-speed MissingLinks to connect it. With two-piece connecting links, if it snaps together snugly such that you can't easily separate it by hand, you can be pretty confident no forces from riding will be able to separate it either.

Another approach would be using Shimano 9-speed replacement pins, and then prepping the KMC part to be inner links, since the replacement pins have to go through Shimano outer links only. This would physically go together but it would be against Shimano's warning of only connecting the "leading" link this way, supposedly for strength purposes.

SRAM 9-speed PowerLinks work the same way for most intents and purposes, and a lot of people use them without issue for any 9-speed chains.

What you shouldn't do is press a pin that's been partially driven out of a 9-speed chain back in to the outer link, because it can cause failure.


When should the metal clips be replaced on a brompton folder?

The Brompton owner's manual states:

  SECTION K: ROUTINE REPLACEMENTS.
  Planned replacement is advised to ensure both safety and good performance. The suggested intervals between replacements are for bicycles subjected to normal use: the most appropriate timing depends on the conditions of use and your riding style.

  ALUMINIUM COMPONENTS: as on other lightweight machines, aluminium alloy is used in
  the construction of the Brompton, and this material has a finite life before failure. In normal use, the risk of aluminium fatigue failure is remote, even after many thousands of miles. However, the risk of failure increases with use, especially with hard riding or other severe loading: as such a failure could cause injury, the hinge clamp plates, handlebar and chainset should for safety be replaced every 5,000 miles (more frequently on any machine subjected to hard use), and we recommend that these items are anyway checked regularly.

As the manual itself notes, that is an extremely conservative number, but considering the hinge plate itself is a £4.00 part it seems better to err on the side of caution.


looks normal to me. There is oil in the bottom of the fork that lubricates the fork stanchions during use. There are rubber seals that hold the oil in the bottom of the fork, but they are not going to be 100% effective. It is this minute amount of oil you can see on the bottom half of the stanchions and nothing to worry about.
Eventually the seals will wear out and you'll need to replace them, along with the oil in the fork. You'll know that you need to do this when it becomes more than a film and you start getting clumps of dirt and oil together. Keeping everything clean and changing the oil frequently will improve the life of the seals and would recommend at the least to wipe the stanchions after every ride with a clean, soft cloth to remove any dust and dirt.


It will have no negative affect on your bicycle to leave the bike in a trainer for long periods, assuming you have the trainer properly adjusted for the width of your rear axle, and that you do release the roller from the tire as you noted.

In addition, in response to your comment, it will not affect the trainer at all, either.


Rear cassette 'ticking' forward, making chain catch, what is the problem and how do I solve it?

Most likely the free hub is sticking.  The grease can get old and sticky.  Service the hub.  Lots of videos on youtube. Or take the hub to a shop.  And you can wear out a hub - some parts are serviceable.

Sticky hub is not likely to break a chain but it is a problem that needs to be corrected.


How does a bike's weight affect the overall experience of owning it?

Other than the obvious fact that your better quality (and better handling) bikes tend to be lighter, there's no real correlation between weight and performance (other than a modest effect on acceleration and the obvious effect on hill climbing).

But you can generally (with some exceptions) assume that a bike that is quite a bit (like 2x) heavier than others of the same basic style is poorly made, with poorer quality components.  Eg, hubs and rims are apt to be stamped steel rather than machined aluminum, the crank is likely a solid steel one (with large, crude bearings) vs a 3-piece one with alloy arms and better quality bearings.  The spokes are probably just plated steel rather than stainless.  The pedals are probably stamped steel, and when you spin them you can hear the bearings rattle.  And the tubes in the frame will be so thick and heavy that the bike will feel stiff and "dead".

That said, there's no need for a beginning cyclist to find the lightest possible bike.  Eg, a good quality steel frame will be maybe five pounds heavier than the equivalent aluminum one, but the steel frame will be cheaper and more durable.  Other components may be heaver or lighter as well, making possibly a 10-15 pound difference between two essentially identical bikes, but beyond a certain point lighter, more expensive components (eg, drilled brake levers, ultra-thin tires) are less durable than their slightly heavier counterparts.

Finally, if you're still tempted to spend an extra $300-3000 to get that ultralight bike, ask yourself how much you weigh, and whether you couldn't afford to lose a pound or two.  The heaviest thing, by far, on a bike is the rider.


There are three main settings on your cleat:

Fore-aft position, which should let you pedal with the metatarsal heads over the pedal axle, more or less;
Lateral position, which should let a few free milimeters between the inner part of the shoe sole and the crank arm;
The most important for you, which is the ANGLE between the longitudinal line of the cleat and the longitudinal line of the shoe.

For the third setting, you have to consider that SPD allows for some lateral play of the foot over the pedal. The position you pedal naturally MUST be the "midway" between each lateral-limiting position. Mind that human feet are not naturally parallel, the heel is a bit inwards and longitudinal lines of both feet describe an angle, which varies from person to person.

Pedalling with your cleat "locked" against some of the limiting positions induces a terrible stress on the knee and the ankle. You should take a tool with you for a setup ride (usually 4mm allen), and keep setting up as many times you need until you feel comfortable. Olny tighten it fully after having found the right position, since the cleat bites the shoe sole permanently then.

As for unease to clip and unclip, you'll get used to it, but you should start using the lowest spring preload that is enough to keep you cliped even when pulling the pedal up with the shoe. A minimal amount of oil on working surfaces might ease things in the beginning, but SPD pedals don't typically require constant lubrication.

Hope this helps!


How do I tell if a loose chain is because of the chain or the ring wearing?

Measure the chain. You can use a chain gauge, or just a metal ruler.

Sheldon describes it in detail, but assuming you have a ruler with inches (and fractions of an inch), you can just measure 12 pins' worth of the chain (under tension). If it it's 1/16th past the inch mark, he recommends changing it.

That linked page also has some information on checking for a worn sprocket: if the chain is new (or you measured and it hasn't stretched), and the sprocket is worn, the chain rollers won't sit evenly between the teeth when under tension.

If you can see light between the sprocket and chain, it's probably time to replace.


Shimano 9-speed shifters high-end vintage vs low-end modern

I just recently replaced my 9x3 105 shifters with the new Sora shifters.  They don't feel any cheaper than the older 105.  Same functions.


In which should I let my gears when not biking?

Don't worry about it, it really doesn't matter what gear you leave it in.

Can't comment so, this is a duplicate of this.


Why does my vintage Shimano rear derailleur come with brake style cable housing?

I assume that you have a friction shifter?  A friction shifter is one that does not click into an indexed position. You just adjust it until the derailleur is lined up where you want it.
Assuming this is the case, the brake cable housing is what you should be using because it was the stuff that was around when those derailleurs were designed.  The compressionless housing, which is what the indexed shifters of today need, came about specifically for those shifters.
If my assumption is wrong, and your shifting is indexed, someone put the wrong stuff on there.  If it is working for you I don't think you need to rush out and change it, but as soon as the shifting gives you trouble, you know why, and it is time to change it.


Can I convert rim brake to disc brake on road bike?

Rim and disc brakes have completely different mounts. The front disc would be mounted at the bottom of the left fork leg, and the rear would be mounted where the seat and chain stay intersect.

It’s not just the mounting points: the tubes in disc brake bikes are different. the carbon layup is denser or the metal tubing is much thicker at the disc mount point and other places that are affected by the very considerable torque generated when you brake.

You might be able to replace your fork with the Propel disc fork, and mount just a front disc brake. This would not be economical. Also, it appears that the fork crown may be integrated with the frame, so I am not certain what third party options are available. You’d also need to change to a front hydraulic shifter/brake lever. You could just use mechanical disc, but compared to good rim brakes, the advantages aren’t huge. Search on the site for discussions of mechanical versus hydraulic disc.

You can get deep section carbon rims for rim brakes. These have some downsides - the braking is inherently inferior to aluminum rims, and you have to use special brake pads. Depending on the resin used in the rim, it’s possible to overheat carbon clinchers on long descents if you brake for extended periods. In that case, the problem isn’t trivial: you would damage a very expensive rim and you’d need to replace it. For reasons I can’t quite remember, tubular rims are less vulnerable to this issue, although they still have carbon brake surfaces, and tubulars need a different chain of logistics than clinchers.

Hybrid rims, like the Hed Jet, Bontrager Aeolus Comp, and some Flo Cycling rims, have a non-structural carbon fairing bonded to an aluminum rim. These are relatively heavy, but weight matters surprisingly little in cycling. (We are talking a wheel set weight of 1900-2000g for hybrid rims, versus 1500g or so for a full carbon clincher wheel.) Opinions may differ, but I would consider these if you’re set on carbon wheels.

Rim brakes are outdated in some sense. However, speaking from experience with both rim and hydraulic disc brakes, you’ll do fine on rim brakes! Good quality rim brakes have more than enough stopping power on alloy rims in almost all circumstances. That does need one minor caveat: your bike seems to have Giant-branded direct mount brakes that are positioned in non-standard locations for aerodynamics. I’m not certain how good those calipers are. It’s possible they under-perform substantially relative to normal rim brakes. However, the point stands that it is completely un-economical to convert your front brake to disc, and that there is no way at all to mount a rear disc caliper.


Why are emergency inflation cartridges filled with CO2?

CO2 charger cartridges are used for bike tire inflation because they are a common, inexpensive product that has been around since the 1950s. Their other uses include powering air guns and inflating life vests.

They were originally developed by the Crosman Corporation and marketed under the name "Powerlet".

Powerlet cartridges are filled with CO2 presumably because it's the most suitable gas. Reasons I can think of are:

CO2 turns into a liquid at relatively low pressure compare to other gases -
liquids are much denser than gasses so a useful amount of CO2 can fit in a small container.
Containers are easy and cheap to make to withstand the required pressure
CO2 is cheap and easy to make (although probably not very environmentally friendly).
CO2 is inert, will not react with the container material. It isn't flammable but heating a cartridge probably isn't a good idea.

Updates to my answer seeing as it popped back up on the main page for some reason.

CO2 cartridges are not filled with compressed CO2, they are filled with liquid CO2. That has to be done to get enough of the stuff in the cartridge to be useful. The cartridge is not completely filled however, and the gas pressure in the space is essentially constant (the vapor pressure) as long as there is some liquid CO2 remaining.

You can't put liquid air in a cartridge because it's comprised of nitrogen, oxygen, water vapor and CO2, all of which have different boiling points. In fact, C02 turns to a solid before nitrogen turns to a liquid.


Do dirty brake pads cause them to wear faster?

Yes, dirt is a realistic cause for increased brake pad wear

According to Chain Reaction Cycles

  Organic pads – also referred to as ‘resin’ pads – are made from a high-density ceramic and have a softer compound than metallic sintered pads. Organic pads generally provide better stopping power and heat dissipation, which means that they are slower to heat up and so are advisable for use in braking systems with a low boiling point. However organic pads can wear out more quickly in wet and gritty conditions.

  Sintered pads: Also referred to as ‘metallic’ pads, these use a compound with added metal content – usually copper shavings. This makes them noiser, and they heat up faster, but in wet conditions they last far, far longer than organic pads. Ultimately your choice may depend on the prevalent conditions you ride in, with sintered pads advisable for the typical wet/mixed weather encountered in the UK (unless you have no problem changing your pads often).http://hub.chainreactioncycles.com/buying-guides/components/brake-pad-buying-guide/

It depends on many variables but cleaning the pads after each ride might help.

The dirt on the pads at the end of a ride won't be there at the beginning of the next ride.

If the next ride has less dirt then not having the previous ride's dirt might help a lot.
If the next ride gets dirty quickly then the benefit is reduced.

Sintered/Metallic Pads

There is an on-going debate over the wisdom of switching from resin to metallic
According to Shimano:

  The SM-RT30/53/51 rotor should be used together with resin pads. If it is used with metal pads, the pads will wear out very rapidly. https://si.shimano.com/pdfs/si/SI-8JW0A-001-ENG.pdf

Determining what works best for you would require some experimentation.


Converting my bike to use quick release wheels

It's a definite MAYBE. You'd have to rebuild the "bolt on" hubs you have to replace the solid axles with hollow ones, or replace the wheels entirely. You'd not have "lawyer lips". And the existing axles may be oversize and QR wheels might not fit well, or there may be other reasons why the skewers will not clamp tightly enough on your frame.


Stuck Compression Plug and Top Cap Screw

Thanks for all your help!

What worked
Drilling with a small bit into the edges of the broken top cap screw.
Miraculously, I noticed that the screw loosened itself as it's unwinding little by little from the vibration of the drilling.
Then I used some pliers to unwind it out and was able to find a near-perfect hexagon hole where I can stick my 6mm in.
Mis-diagnosis?
So...the top cap screw thread doesn't seem to be burred or damaged. Even cosmetically it looks fine.
The black anodising on the thread is consistent and no bubbles or cracks can be seen.
But I'm actually really curious, and want to prevent this from happening again!
Please leave your thoughts below so we can learn more from my mistake together.
Did I start the drillium too early? Was there another solution?
TLDR;

Loose headset, and top cap bolt stuck.
T25 top cap bolt stripped.
Araldite in the bolt and on my T25 key, left it over 2 nights, didn't unscrew.
Top cap bolt is aluminium, compression plug bolt is steel.
Drilled off top cap, left an even more stuck top cap bolt in compression plug.
Drilled out top cap bolt, bolt seems perfect.
Please tell me why top cap bolt is even stuck in the first place.

Thanks @Michael and @Carel.
Guess drilling really helped in the end!


Calves overcoming glutes function, is this a set up problem?

Cycling is a quad dominant sport and many cyclists can become quad dominant in their everyday movement patterns which can affect body posture and core stability muscles such as glutes. If your main daily activities are riding your bike and sitting down in a slouched position you may find that over time you may lose the ability to effectively fire your gluts.

In addition to this, Glute recruitment is also affected by hip  position on the bike, which in turn can be affected by the saddle angle, saddle profile, flexibility of the rider along with individual movement pattern habits. Many modern saddles have a flat profile, which can encourage you to roll the top of your hips backwards, which can inhibit core muscles and turn off glutes from firing during the pedal stroke. In contrast, saddles with a swooping profile allows the top on the hips to be rolled forward which encourages glute recruitment. If you have never ridden this type of profile it can take some time to get used to, as you may instinctively want to roll the top of your hips backwards out of habit, which result in contact hot spots and discomfort.

You said you were able to get your glutes to fire at faster speeds (i.e., 30+ kph). I assume this is seated harder efforts. Under harder efforts you are concentrating more, sending a stronger signal down your central nervous system which may be enough to recruit your glutes. Lighter efforts the signal may not be strong enough. This could indicate that your glutes have become weak, and/or your general ability to fire glutes has declined. The only way to really reverse this is by practicing daily exercises designed to help you fire your glutes.  Also when you are climbing out of the saddle focus on rolling the top of your hips forward when standing this will help encourage your glutes to fire .

Not sure what is going on with your calves. It may reflect cleat placement (I.e., foot position on the pedal). It may be unrelated to your glute firing issue. Another possibility is that it comes out of compensatory behaviors that result from poor hip position and strength.


Could I add chain rings, front derailleur, and shifter for the front derailleur from other bike?

Maybe.

Here are the issues:

Shape of the seat tube. If the seat tube is not cylindrical or too wide near the chainrings you wont be able to mount a band clamp derailleur.

You have a 3 piece crank with crank arms separate from the bottom bracket axle, with a square taper type crank-axle interface. If the multi-chainring cranks you want to mount are the same you can mount them also.

Getting the right chainline. Different cranks have the rings at different offsets from the square taper hole, and require different length axles to position the rings correctly. If the chainline is the same on both bikes and the axles are the same length then you can make a direct swap, otherwise you'll need to calculate what length axle you need and get a new bottom bracket.

Chainstay clearance. The single front ring bike may not have enough clearance for a multiple chainring crank.

Front derailleur cable housing mounts. If your frame does not have `em, you'll need an alternative. I believe there are ones you can clamp to you frame available.

You'll need a new chain as the required chain length will be longer (assuming you are adding a bigger chainring).

You'll need to check that you rear derailleur has a great enough total capacity Otherwise it will not be able to handle the increased variation in chain slack. Capacity needed is (difference in size smallest-largest sprockets) + (difference in size smallest-largest chainrings)


Some people do tour with Bromptons, so don't rule it out: Touring on a Brompton, Brompton cross country touring, The genius of Brompton touring, Brompton touring.

I don't know about France, but in the UK, not all trains allow large wheeled folders. If they do, something like a Dahon Espresso is a quick fold, but not very compact (folding handlebars help, and newer models have them as standard). The Dahon Cadenza is slightly less bulky, but slower to fold.

The Jetstream is 20" wheels, doesn't fold as small as some other small wheel Dahons, but would cope with some sorts of touring better because of the suspension compensating for small wheels to some extent.

If you ever want to take the bike on a bus, you will almost certainly need a small wheel folder.

Another possibility is a Riese und Müller Birdy. They do get seriously expensive, but fold nearly as small as a Brompton (compared with a large wheeled folder; if your main use is commuting with public transport, the Brompton fold is enough smaller and neater to matter). (There is now longer a Birdy model specifically named "Tour", but they are still used for touring.)

(Photo below from http://www.pbase.com/image/83944065 is an older model Birdy.)


What is the widest tyre that you can get away with, on a standard road bike?

With a bike designed around modern "short-reach" 39-49mm calipers, you're going to four main issues:

1) Brake clearance vertically.  If everything else is optimal, a 49mm reach caliper should be able to clear around a 32mm tire.  You can verify this with an unmounted brake.

2) Brake clearance horizontally.  Extra cable tension releases (e.g. in levers or inline) help with this, but the maximum width that the calipers can spread will not be enough to allow an inflated tire through, and even with a deflated tire you might have to force it.

3) Frame clearance. You'll need to have adequate clearance in three places: seatstay bridge, chainstay bridge, and fork crown.  In extremely aerodynamic frames, you also may have issues with seat tube clearance.

4) Rim width of your current wheelset.  The Campagnolo Eurus wheelset has a 15mm wide rim.  The general rule of thumb is that a tire should be no more than 1.45 to 2.0 times the rim width, which would limit you to roughly 30mm wide tires at the biggest.

In general 23mm should be expected, 25mm is likely, and 28mm is occasionally possible.  What actually works on a given short reach frame is going to be heavily dependent on the factors above.  Bikes with medium-reach (57mm) or long-reach brakes are more capable; I do road riding on a classic 27"-wheeled Trek refitted for 700c with long-reach brakes, 33.3mm tires and full fenders.


Why don't race bikes have solid front triangles?

Much of this is due to UCI regulations. They specify what shape and size of frame can be used. It is not allowed to add extra parts just for improving aerodynamics.

See the UCI document Technical Regulations For Bicycles - A Practical Guide To Implementation (PDF) which covers most of this.

As it says for Article 1.3.020, the frame elements must be tubular, with a maximum transverse dimension of 8 cm and a minimum transverse dimension of 2.5 cm, in a maximum ratio of 1:3. Also Article 1.3.024 "Protective screens, aerodynamic shapes, fairings or any other device that is added or forms part of the structure, and that is destined or has the effect of reducing wind resistance, are prohibited."

It could be possible to make a more aerodynamic bike that was not allowed by the UCI. But you would be restricted by what races it could be ridden in. A few brands have mode non-UCI compliant race bikes, mostly designed for triathlon. eg some versions of the Specialized Transition or Shiv, which have extra aerodynamic tubes etc.


Skinny 26" tires? Giveing a small fixie a “faster” look

If your LBS doesn't stock speedier/skinnier 26" tires, you might have to order them (either through the shop or online somewhere).

They are a bit less common, but here's four options I found looking at some major tire manufacturer's websites:

Specialized All Condition Elite (26x1.0 available)
Schwalbe Durano 399 (26x1.10 and 26x1.35 available)
Continental Sport Contact (26x1.3 available)
Schwalbe Kojak (26x1.35 available)

Keep in mind:
There's limits to how narrow a tire you can reasonably put on a given rim.  If you go too narrow for a given rim, you'll get pinch flats and possibly even rim damage. Sheldon Brown's site has a helpful chart of tire width and rim width compatibility.  What is the (interior) width of your rims?  Or at the very least, what size tire do you have now?


Will the Shimano HG41 match nicely with a Shimano Claris derailleur?

In short: Yes.

I bought said bike, and tried the new cassete. It works on both big and small front rings, but the derailleur arm gets very very stretched on the big one. My opinion on this is that the 32 teeth maximum limit has a bit of a safety margin, so if in the next 100 km something bad happens, I'll update the answer. Otherwise, problem solved.

And I will try to avoid using that low gear, unless necessary.

Also, here is the resulting derailleur position on the worst possible scenario, which I avoid:


Do rubber bike pedals or rubber pedal covers exist?

A short length of foam pipe insulation should do the job.  It's cheap, will fit into your pocket, and you can get it at any hardware store or plumbing supply shop.  You could also slide it onto your top, down, or seat tube for storage.

It looks like this:

Choose the size based on the type of pedals you use.  Platform pedals will require a larger diameter and clipless pedals a smaller diameter.  You want it big enough so you can easily slide it over the pedal but small enough that it stays put.


At the bike rental store I had we rented single speed cruisers. Single speed and mulit-speed, done with multi-speed hub (sometimes called internal gearing, hub has a single drive gear) is usually 1/8" width size 1/2" spacing, generic stuff. Lots of choices for plating and color if you want a little fancy or rust resistance. Now when you say multi-speed with rear derailleur, there's the kicker. You'll need a little skinnier to get through the drive-train. Get a generic 3/32" multi-speed chain my best guess for Huffy match. You see any word on the derailleur (for example) like Shimano or other brand?? Buy specific to gear train brand for best performance and also to number of gears too. For example you could be rocking a 5-speed cruiser with a low end Shimano derailleur, probably with a big cage between gear pulleys. In this example case, I recommend (not brand, just example) but I'd match brand, so buy Shimano/ 5spd/ multi-speed chain. Use the old chain to match number of links, but don't trust it for sizing. Chain stretch is a real thing, sometimes 1-2 full links. I've seen great YT videos for chain sizing on both types of drivetrain. FYI, fit on a single speed is adjusted with dropout and length so the chain is no looser than about a 1" bounce to it.


At the shop we generally use a "normal" hacksaw blade. I'd go with finer blade (more teeth per inch) if there's an option. Go slow and smooth (long low pressure strokes) and keep the blade perpendicular to the bars. The tape will probably help but do take care removing the tape or you might cause the fray you're trying to avoid.

There are special carbon cutting blades. We tried these and switched back to hacksaw.

Happy Riding!


Riding on a failing bottom bracket - what could possibly go wrong?

Eventually your bearings will disintegrate and your BB will lose its ability to hold the spindle centred withing the BB shell, that will result in the crankset becoming wobbly, your chain will come off, your chainring might even go hit your chainstay and if you're lucky it will happen at low speed.

Here's a BB I personally exploded on my fixed gear commuter

Everything I described above happened and I would not recommend running a clearly faulty BB for too long.

I believe a BB using bearing cartridges might not fail as catastrophically as one with simple cages like the one pictured but I doubt it would end well in the long term.


Cheap energy sources for electronics during touring with low amount of sun energy?

Assuming you add the robust stand you were talking about here it should be possible to pedal the bike on the stand. Even pedalling gently will give you 50-100W of mechanical power that you can use to spin a small generator. I suggest looking for a dead RC toy and using the motor from that, since they often use that level of power. Ideally drive it from the chain rather than the tyre, but focus on making it work to start with. A little work on voltage conversion should give you enough power to charge the laptop fairly quickly, and with a little work you could even use it while pedalling.

Otherwise a hub dyno. A decent bottle dyno will not be much cheaper but will need more maintenance.


Looking for ideas - Decent cheap 26" 1 1/8" suspension fork for 1996 Trek 950 mountain bike

Honestly, it seems that you want too much of everything at the same time: cheap, good, compatible with your depreciated frame suspension fork. You might reconsider your constraints.

Compatibility comes first, otherwise there is not much sense in getting a new fork. You'll need something for 26" wheels and with a straight 1⅛" steering tube, which is not what modern forks offer. I would say the majority of aftermarket suspension forks are for 27.5" or 29" wheels and likely to have a tapered 1⅛" - 1½" steering tube.

Then you have two remaining exclusive options in the requirements space.

Cheap — find a new OEM fork for entry-level bikes. There are decent chances to find something for 26" wheels, with V-brakes and straight steering tube. But such a fork is not likely to turn out to be "good" in terms of suspension performance and longevity.
Good. Go for a hunt on vintage market or consider having a modern fork with all mandatory upgrades it brings with it. Neither option would be cheap. For example, a new MRP Loop SL for 26" and straight steering tube costs USD 800+. Add to the price the front wheel change (through axle), front bake change (disc brakes).

Yet, finding a used old fork still looks more promising, and there is always a chance to find a deal.

On the last compatibility note, the 60 mm of travel is something not commonly seen for MTB these days, even on entry level forks. There is e.g. Lauf Carbonara gravel
fork, but it is not something you'll want; besides, it is not straight steerer neither for 26" wheels.


Are seatpost shims safe to use - for the frame, seatpost, and the rider?

Longer is better – it helps stop rattling if the seat post is longer than the shim and banging the seat tube, although if that happens you can always cut down the set post.

As far as safe to use – as long as the shim is at least as long as the minimum seat post insertion required for the frame, in theory you are stressing the frame no more than using the correct diameter seat post.  Many frames do require 100mm or more, and many seat post shims are not 100mm.

On carbon I would hesitate – if you spend that much on a frame, you can afford a new seat post, but some posts (e.g. MTB Droppers) come in limited sizes so you don't get much choice: new bike or shim.

Factor in your own weight (I am a lighty) and riding style (I am a wimp on the MTB) and decide how much stress you put on the frame compared to others. Would I use shims? Certainly, on steel and aluminum frames, and probably on carbon if I had no other option. If a 100kg 20yo downhill rider asked if he should shim his off-season Carbon XC race bike to put on a dropper, I think I would suggest not to.


Do I need to use the QR Skewer that came with my trainer? What sort of lubricant do I need to use?

You should use the QR skewer which came with the trainer for several reasons:

1) Its cheap and ruining it (rather than your own skewer) will keep your nice skewer which came with the bike in good condition. It may also be stronger than your (possibly boutique) skewer in the trainer. (Safety)

2) It has markings which can help bite into the cups of the trainer which attach to the skewer. (Safety)

3) Liability -- the manufacturer said to put it there. If you don't, you're SOL if it goes wrong with the skewer. Plus, it takes about 5 seconds to swap the skewers so why not do it?

That being said, as you found out, many enclosed cam QR skewers will fit into trainers, but why risk it? I would not recommend it (as the trainer manufacturer probably wouldn't either).

The lubrication of the QR skewer is for the cam - you don't need to do anything for a new skewer.