Slight hub problems...

Today I noticed that my KH hub is slightly twisted. It makes absolutely no difference when riding and I can’t feel it when on the unicycle but it’s got me worried. Could I be doing anything wrong maintenance-wise? I’ve been sure to tighten everything up properly and I’ve only done drops up to about 4’ so far on it. I just don’t want it to get any worse because it’s a nice hub.

Andrew

What exactly do you mean, “twisted”?

Ummm… speaking of twisted…

brianclowntrials.jpg

Well imagine that the axle has been gripped at each end by two things (let’s say cranks :)) and each one has applied pressure in opposite directions. If you removed the axle and rolled it along a flat surface, from the looks of things it would roll smoothly without bumps. It hasn’t ‘bent’, it’s just ‘twisted’. You can notice it more in the flesh than in the photo I’ve attached. I also noticed that the right (back) crank is slightly bent as well although once again it’s not much at all and you don’t notice it when riding.

Andrew

You probably won’t see the bent crank at all but here goes…

Have you tried taking the cranks off and looking at the splines? If the splines have actually twisted it will be obvious when looking at them. Instead of the splines being nice and straight they will have a little rotational twist.

Try taking the cranks off and putting them on with a different orientation. Make sure there is no dirt or crud on the splines, but clean grease or anti-seize on the splines would be good.

Are you sure all the bolts are tight? Put some anti-seize on the bolt threads and then tighten them up again. The anti-seize will allow you to get the bolts much tighter than you can with dry threads.

I would be surprised if you managed to bend or twist the hub. My guess is that the pinch bolt on one of the cranks is not tight enough and that loose pinch bolt is allowing one of the cranks to sag.