getting cranks off.

After buying a new Nimbus II 20" Unicycle, I rode for a total of 2 hrs and destroyed the right crank by pedal coming loose.

I bought new cranks and tried to switch them out, however, the allen screw wont come loose. I’m afraid I will ruin the allen screw from “cranking” on it to hard.

Which direction do the right cranks loosen? I’m using an 8mm allen wrench.

How much torque can I use before I strip the allen head?

Thanks for your help

righty tighty lefty loosey

that’s the way I was turning it and it wont budge

do you have a crank puller?

I dont have a crank puller. I do have a wheel puller for fly wheels and fan blades though…

OK, I got the allen screw out without damaging it. Now a crank puller would come in handy :):slight_smile:

The allen head bolts are pretty hard to strip in my expierence, especially if you are using the right size wrench. It should be very snug in the head of the bolt. Remember only the pedals are treaded differently than normal, not the bolts for the cranks. After removing the bolt you will need a crank puller to remove the cranks. As far as I know there is no way to remove any crank (square taper, ISIS, other splined, etc.) without a crank puller.

Thanks Shady.

I’ve stripped out allen heads and have broken allen wrenches before (not on uni’s though) so I was a little nervous because there was a little bit of ‘play’ in the allen head with the 8mm allen wrench. But, I said screw it and, well, unscrewed it:D and lucky for me, I only have to buy a crank puller instead of a hub (or at least the screw) along with it…:wink:

While true at the axle, remember it’s different at the pedals. Then it’s righty-righty and lefty-lefty. In other words, the right-hand pedal tightens normally, and the left one is reverse-threaded.

In your case, the left crank may be on the right, and the cause of your problem…

While you finally succeeded in loosening the Allen bolt, a useful trick to remember is to increase your leverage by lengthening the shaft of the Allen wrench. You can do this by removing your seat & post assembly and slipping the seat post over the wrench shaft - instant increase in leverage.

well, I just ordered a crank puller, and a bunch of other stuff to build another unicycle to replace my old 24" :smiley:

I know the KH splined cranks can be pulled without a crank puller… Very useful for when you rotate them…

Are the splined the ones that require an Allen wrench?

How do you pull the crank off after you remove the “hub” with the Allen wrench?

Strange – I find I always have to use a crank puller with them.


I changed cranks on my freestyle fine a couple nights ago but when I used the same multi allen wrench tool on the cranks on my muni I broke the tool:

nice video on crank puller use

My KH cranks are on so tight that I could probably ride for a long while without the bolts in. I don’t know how you manage to remove them without a puller.

Yeah those multi tools are never going to stand up to those allen heads. Maybe the alluminum ones. I just find it easier to keep an 8mm (like the one UDC sells) handy.

Also if you need a cheater bar (seat post) you either need a longer wrench, do some exercises or they were tightened down way to tight. 25ft lbs is all you need for ISIS. Someone said 50 Ft/lbs and I tried going to that once and my built in feel for the danger zone of tightening said uh-uh too tight. So now I just tighten them nice and tight with a wrench and check them from time to time. Nice thing about a Uni is you can check every fastener in less than 5 minutes.

An easy way to remember about pedals is to tighten them you turn the wrench forward as it goes over the top on both sides. To remove the wrench turns backwards (towards the rear of the uni. Just remember this is as the wrench goes over the top.