Help! I had this problem early when I bought my onza unicycle. Whenever I do something that stresses the cranks, and then push the crank in the other direction, they move. Today I lubed up the splines, and it still does it, just more quietly. The cranks are as tight as they get. Help!!! Also, I did go a period of time when the thing only creaked, and there wasn’t any play, but now there’s most definitely play mad: 
. I bought this thing so I’d stop having to worry about my equipment, but feeling that mavement after a gap or during a jump isn’t exactly encouraging me to push my limits. Have any other Onza owners reported this problem? Please, help.
Did you also anti-seize the threads of the bolts?
my onzas work fine
That’s what I thought it was early on, but then it stopped. A loose keyway is very unlikely. Also, at one point I only felt it in my right crank, but now it’s both. If it’s only one side, it’s probably not a loose keyway.
I don’t anti-seize the bolts, although I did grease them. They should be tight enough, though. I got them to the point where I couldn’t really get them any tighter without getting someone else to hold the wheel and me turn the wrench by pushing with my leg.
I’m wondering, is this a manufacturing flaw? Should I call uni.com and exchange it. I’ve never heard of messed up Onzas, and I only weigh about 120lbs, so I’m not very heavy. I’ve only done about 3 drops over 3’ with it (roll out, of course), too, so I’m not all that abusive to the equipment.
Hopefully it’ll hold up until the summer, when I can get a profile set for my muni and possibly the onza.
Again, I ask for help. Has anyone else had this problem?
It has the symptoms of a loose keyway. If you’re looking for a way to make a positive confirmation of the diagnosis you could try the following exercise.
Take the wheel off the uni
Remove the cranks, spacers, and bearings
Clean off the spindle
Slide the cranks back on leaving the spacers and bearings off
Have one person hold the wheel
Have another person push and pull on the cranks as if pedaling
Look for movement of the spindle relative to the hub body
Any movement would be slight and may not be easy to see. You could try scribing a fine line on the hub body and spindle to make any movement more noticable. It may also require quite a bit of force on the cranks to cause any movement.
resurrect
I fear the movement will be too fine to notice. Would it be something I should return to uni.com if it is loose? Also, will it get worse if I don’t do anything to fix it? I don’t particularly like hub dissection, and also I ride enough that finding time to fix it will be difficult, just like finding time to clean my leg armour.
Thanks John, Oh Great Unicycle Repair Guru.
I don’t know what the warranty is on the Onza or what unicycle.com would say. Give them a call and find out.
The hub shouldn’t get noticeably worse if you just let it be. I left mine for a while after I knew it was the keyway that was slipping. I finally decided to fix it when I had my muni apart to fix my broken Profile crank.
The operation to fix a splined hub doesn’t take long. Just a couple of hours and you could be riding it 12 hours later after the Loctite cures. You could fix it in the evening and be riding it again after school the next day. Don’t you have access to a metal shop? A metal shop will have all of the tools necessary to take the hub apart and put it back together.