I am working right now at a Unicycle Camp in California, alot of my students have the nimbus trials uni.
The problem is that on the right hand crank the pedal is stripping the threads from the crank. All of these unicycles are less than 4 months old and have not been ridden hard at all. They all have qu-ax cranks on the uni.com cromo hub. It has crossed my mind that perhaps the pedals may have been cross threaded and that riding on them for a while may have caused the crank to strip out all the way.
Is this a major problem for other people too?
Is there a bunch of defective cranks out on the market that have been recalled?
You can probably imagine that these students are very dissapointed in their new unicycles, I would like to try and help sort out the problem if it is possible, but I’m not sure that just putting re-tapping the crank will help. Should I contact unicycle dot com and see if they can do anything, or should I just tell my students to buy a new set of cranks.
If the pedal has stripped the thread out of the crank 999,999 times out of a 1,000,000 the wheel has been put into the frame the wrong way round. So as you ride along the pedal can loosen and if you ride with a loose pedal it will strip the thread out of the crank.
Aluminium cranks will strip faster than steel cranks because they are a softer metal so you need to be more careful about putting the wheel in the correct way round.
To make it easier to see which way round to put the wheel in, both the cranks and pedals should be stamped with an R or an L to signify whether they should be on the right or lefthand side.
If you explain this to your students hopefully they will stop destroying cranks, because if they buy new cranks and put them back on the wrong side again they will just strip the thread again.