replacing cranks

i know that this is a REALLY stupid question, but i have no idea how (or what tools are necessary) to take a crank off of my uni. It really sux cuz i got a pedal stuck on (missed thread) and my pedals are gonna wear out.

Assuming you don’t have some funky cottered crank, there should be a bolt you can unscrew to take off the crank. There might be a cap covering it that you should be able to pry off with a screw driver.

You need to take out the bolt then use a crank puller. Available at any bike store or UDC

You likely wouldn’t have to buy one, at my store they pull em off for free. It takes like 30 seconds.


get a crank puller! you can buy them at you LBS usually no more then 20$ its kinda like a ratchet. i applied as much bruit force and ignorance as i could muster without a crank puller and would not budge.

This could’ve been me.

This is the tool that you want: Park CWP-6 or the older CWP-5. The older one has 14mm socket at the end while the newer one has an 8mm hex (allen key) head at the end. Most unicycle hubs use the 14mm nut so the older CWP-5 would be more convenient if you can find one. You’ll also need an adjustable wrench to go along with it.

There is also the Park CCP-2, but that one is less convenient for unicycle use because you have to remove the pedals to be able to use it. The problem is that the handle is too long and the pedal gets in the way.

Here’s a picture of the CWP-6 in use and instructions on how to install/remove a crank. There’s lots of other repair tips at the Park Tool web site.

Re: replacing cranks

Not a stupid question at all.

And we can continue this thread when you need to put cranks back on the unicycle. That should be a much more lively discussion (the hammer vs. torque wrench camps can, um, hammer it out).

It’s just soooooo much easier than everyone makes it sound.

Remove the cap with a screw driver.

Remove the nut or bolt (it varies) with a 14 mm socket.

Use a proper crank puller (around £10 UK, under US$20) to remove the crank.

Keep everything clean. Work methodically. Put the crank back on, and tighten the nut/bolt. Ride for a short distance, then nip the nut/bolt up a bit tighter.

No need for hammers, torque wrenches etc. Just common sense, and a bit of mechanical sympathy.

What about KH splined cranks

This thread comes at a good time…

I just bought 140 mm cranks to replace the 170 mm cranks the KH26 came with. I was going to swap them this weekend.

I assumed that all I had to do was to loosen the pinch bolt, unscrew the axle bolt, and then I’d just be able to pull the crank off with my hands. True? Or do I need a crank puller?

Any advice appreciated.

Re: What about KH splined cranks

The crank pullers mentioned here are for square taper cranks like you’ll find on standard unicycles. Splined cranks like the KH, Profile, Onza and others are different.

You should be able to remove the KH cranks by hand after loosening the pinch bolt and removing the axle bolt. No fancy tool needed. If the cranks have been bent or dented then they may be more difficult to remove. If that is the case then see below.

Profile cranks can be a bit more difficult to remove. In those cases you can use a bearing or pulley puller to pull the cranks off. If you have problems removing the KH cranks you can use the same tool.

Re: replacing cranks

On Fri, 19 Nov 2004 16:51:22 -0600, “Dave Lowell” wrote:

>And we can continue this thread when you need to put cranks back on the
>unicycle. That should be a much more lively discussion (the hammer vs.
>torque wrench camps can, um, hammer it out).

Good point. I used to be in the hammer camp but converted to the
torque wrench camp. My advice for mounting cotterless cranks:

Put grease on the crank arm and/or square tapers, and also put grease
on the threads. That makes sure that as much as possible of the force
you’re applying goes into tightening the cranks. I.e. less wear and
more reproducible.

Tapping with a hammer? WARNING!! Only very light taps are OK. But as
soon as the nut engages enough of the thread, don’t use the hammer any
more. The sudden force of a hammer blow is likely to cause haircracks
to arise near the four corners of the crank hole, and once this
begins, the cracks tend to grow due to the forces of riding and even
of tightening. It is the beginning of the end for your crank!

The crank nut is not easily overtightened. For most systems, the best
tightening torque is around 40 lbs.ft. If you don’t have a torque
wrench, you can use a normal wrench of 1 foot long and lean on the end
with a weight of 40 lbs. Or a half foot long wrench and lean with 80
lbs, etc. This is probably not easy to do exactly, but it gives an
idea about how tight the nut should be. Alternatively, you can put the
uni on a bathroom scale. Use a non-digital one, because most digital
scales need a stable weight to display a value at all. Then orient the
wheel such that you push down vertically on the wrench. Don’t push or
pull on the uni while tightening. Subtract the weight of the uni +
half the weight of the wrench for extra precision…

Klaas Bil - Newsgroup Addict

“Deflating pi does not reduce calories, it just concentrates them. - billham”