crank falls off

ya ive been riding my torker lately and originally i put up a post about my pedal popping all the time when i ride but i discovered the other day that it was actually my crank arm and it kept unscrewing itself and thats what the popping was, any ideas on how to fix it???

buy a crank wrench and tighten the cranks, and make sure they are always tight

Also, be sure to never ride with a loose/popping. It will cause the square taper to get rounded. Once that happens, you’re in a world of hurt. For more info, check

Edit: Don’t forget to grease the taper first.

Re: crank falls off

That is exactly what is happening to me i keep tightening the bolt but in about 2 days it ge really loose and falls off. it is really starting to bug me…


The best way to make sure the crank is properly tight is to use a torque wrench. The crank nut should be tightened to 40 foot-pounds. If it is properly tightened it should stay tight for normal riding and you shouldn’t have to mess with it till it’s time to remove the crank. Things like muni and trials are rougher and can cause the cranks to come loose on their own. If you’re doing muni or trials you’ll have to keep an eye on the crank tightness and retighten things as needed.

Here’s the short run down on how to get the cranks tight:

  1. Clean the hub taper and crank taper of any grease or dirt
  2. Put a little bit of grease on the taper of the hub and/or crank
  3. Slide the crank on
  4. Put a couple drops of red high strength Loctite threadlocker on the crank nut threads
  5. Tighten the crank nut to hand tight
  6. Use a torque wrench to get the crank nut to 40 foot-pounds

It is difficult to estimate what 40 foot-pounds is without a torque wrench. If you don’t get the crank tight enough it will come loose on its own. If you get it too tight you can strip the threads. A torque wrench is the only reliable way to know if you got it tight enough.

If you don’t have a torque wrench then take it to a bike shop and have them tighten it.

You can do it without a torque wrench and you can learn to estimate what 40 foot-pounds feels like. But you’ll never know if it really is tight enough and you’ll have more loose crank episodes than if you use a torque wrench.

Since I started using a torque wrench I’ve not had any loose crank episodes on my Coker or my freestyle uni (my two unicycles I ride regularly with square taper cranks).

JC speaks gospel. I got one on his recommend for switching cranks on my 36-er, and it works great. And you don’t need to spend up for the ultra cool digital model. Sears makes a very good basic Craftsman torque wrench that will probably last a lifetime. I think I paid between $20 and $30 for it.

edit: just searched on it. It’s this one.