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Cranks and pedals

The hardest work you can find on a bike is pulling cranks off a square tapered axle without a proper tool. They are usually pressed in very tight and they are hard to grab because they tend to be slippery, rounded, five-armed and obstructed by a bunch of frame tubes. What does the proper tool look like? It has a good, deep outer thread to mate with inner thread on a crank without stripping it, and its inner pushrod is capped with a rotating ring of correct diametre which doesn't damage axle threads or the square hole in the crank. If we don't have the pulling tool or the cranks don't have corresponding threads, we're out of luck. If the reason of crank disassembly is replacement of a wrecked bottom bracket, it's OK to destroy it. The gentlest method is to cut the axle with an angle grinder (a thin grinding disk just fits in the gap between bottom bracket and crank) and tap the tapers out comfortably on a workbench. A less gentle and much more tedious method is banging it with a hammer over a piece of wood. What is the advice to take from this? Maintenance-free sealed cartridge bottom brackets which don't need regular disassembly and adjustment are the best choice. And grease the tapers a bit when installing the cranks.

Besides square tapers, there are also splined axles, for example Powerspline or Octalink. They work pretty much the same, the only difference is the contact surface shape. A completely different beast is a hollow axle, for example Hollowtech. Its bearings are outside the bottom bracket tube and the axle is permanently connected to right crank. Left crank slides on a splined end of the axle where it is secured by a pinch bolt.

There is also an older way to connect cranks and axles: cotters. If they are not totally rusted, they are pretty easy to disassemble: loosen a nut, tap it lightly with a hammer and that should loosen the cotter enough to be pulled out by hand. Assembly goes in the opposite direction: insert cotter, tap or press in, then secure with the nut. In use, cotters need regular checking and tightening because they gradually deform and cranks may start to wobble. If you don't insist on genuine vintage components, I'd recommend to replace cottered cranksets with something more modern.

Pedals

What to say about pedals? Nothing special, just note that the left one has left-handed thread, so it screws into the crank counterclockwise. Pedals are quite simple, even the cheapest ones can work reliably for years. And all have the same threads, so replacement is never a problem.

Besides the classic pedals (an anti-slip platform you put your shoe on), there are also clipless pedals (the name is quite confusing because your shoes do clip in them, they just no longer use the old system of straps that clips around the shoes). Their advantage is that your foot can't fall off the pedal and it can push or pull in any direction, which boosts your power considerably (especially on recumbents). The disadvantage is you need special shoes with cleats in the soles, and you need one extra ankle movement to unclip.

There are several types of clipless pedals. Probably the most common one for mountain and touring bikes is SPD (Shimano Pedaling Dynamics). Their only adjustable element is the rear hook tension. It must be strong enough to hold the foot safely, but weak enough to allow quick and comfortable unclipping. I prefer the spring to be pretty loose: just tight enough so that I can't move it with a bare hand. Another adjustable thing is cleat position on the shoe, the optimal position is very individual. The most common recommendation is to put the pedal axle under the ball of the foot, but I like it further back. SPD shoes come in many shapes, including some which look like normal walking shoes, cleats fully recessed in the soles, so you can walk in them without problems.

Road pedals are a different category. They are designed for effective riding, not for walking, so their soles are hard and the cleats stick out.

There are also combo pedals with a platform on one side and clipless mechanism on the other. It looks like a good idea, but it doesn't work for me. In my case, clipless pedals need almost 2 cm higher seat, so I either have to readjust it with every change of pedaling mode, or live with some uncomfortable and unhealthy compromise. Good for experimenting with various configurations, not so good for normal use.

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