Crank Problem

About a week ago, I started noticing a slight slip in my cranks. I stand in one place, preparing to ride/hop/anything and, my cranks will move a bit before my wheel does.

It’s a standard Torker DX 24". I’ve been basically, riding around town, hopping up and down curbs(nothing higher than 6"), and doing a little grassy hill off-roading. I tried to tighten every single bolt in the vicinity and it changed nothing.

The unicycle has only been ridden for about 2 1/2 months since purchased new. I do weigh a bit more than your average rider(230lbs).

I’m kinda new to the whole unicycling thing so, can anyone tell me why this is happening and how I can fix it?

I searched the archives and didn’t find anything that didn’t say, “buy a new unicycle”.

what is youre budget???

Maybe get some new cranks other than that I guess get a new Unicycle. maybe a nimbus 24 or something ?

Stop riding it imediately.

Loosen the cap bolt, remove the crank bolt, clean the threads of the axle and bolt w/ rubbing alcohol, put blue Loctite on the bolt and put it on torqued to 45 ft lbs. Then tighten the clamp bolt (I don’t know it’s max torque, but I’m guessing 25 ft lbs.).

If you don’t have a torque wrench tighten it w/ a normal 8 mm allen wrench as tight as you can. If this happens again, repeat this w/ a torque wrench (yours or have your LBS do it).

If it still loosens up you can try tightening it up to 60 ft lbs, but the head of the bolt may break off. And/or you could use red Loctight, be weary of this, since it’s “permanant” you may not ever get it off again.

If it still loosens up, you need new cranks and/or a new hub.

Missed deadline

I had my cranks at 65 ft lbs and still loosening up w/ red Locktight (I didn’t realize oil had leaked out of the bearings, getting on the threads and the Locktight wouldn’t work). Eventually the bolt’s head broke off. I fixed it at my Junior College’s Machine shop. It would have likely cost me $150 + to fix it elsewhere.

Now I’ve done what I wrote above w/ blue LT at 45 ft lbs and the clamp bolt @ 25.

No problems yet :o

skilewis is on the money, you need to tighten the two bolts on your crank in the correct order, not just heave on them indiscriminately. Personally I would slack the pinch bolt, tighten the crank end bolt, then retighten the pinch bolt, to see if it will tighten up enough to account for the wear you’ve put on the spline interface. If it works then pull it apart and follow the advice above to make it permeanent.

I just performed the necessary repairs to the uni and am waiting till tomorrow to try it out. It’s 4:30am here so, I’m a little tired to try it out and, the loctite package says to allow 24 hours for full strength.

I’ll keep everyone posted on the results, just in case someone in the future needs this as a repair thread.

By the way, I couldn’t find red and blue loctite but, I did find many kinds of loctite. The kind that I got is called “Repair Extreme, all temperature”. The package says, “for bonds subject to rough handling and harsh conditions”. I figured that this application qualified.

This stuff is intended for genreal adhesive work, not as a thread locking agent. While it will probably work, you most likely will not be able to remove the bolt again, without applying extreme heat. Loctite 272 is the stuff you ideally want.

Okay then, next question. What will happen if I just ignore the problem? You said to stop riding immediately. Will the cranks just fall off? Will I break my hub? What will happen if I just keep riding it this way? I understand that the problem will possibly worsen but, how?

The way that I see it(and I’m probably wrong), it’s a tightness issue. For some reason, I can’t seem to tighten the pinch bolt and cap bolt tight enough to keep it from having a little bit of a slip. After removing the crank, I found no issues with the internal connection so, is it just a tightness issue?

Here’s what I did, I loosened the pinch bolt then, tightened the cap bolt as hard as I could. Then, I tightened the pinch bolt back on, also as tight as I could, by hand. I then repeated this on the other side. It fixes the problem for a moment and then just goes back to slipping again.

I’m really just tired of “quick fix” remedies and am looking for some solid facts on what is really happening to my unicycle, how I can prevent it from happening again and, how to properly fix the damages that have already occured.

you don’t want to ignore it. Awhile back i noticed the cranks on my torker were starting to slip but I didn’t think it was that big of a deal so I left it alone, and about a month later the entire right crank snapped off ruining both the crank and axle.

I had this happen to an old bike of mine. In the end it had sheared away the inside of one of the cranks. cycling on it just made the defect bigger and the crank looser.

Is it both cranks or just one? You may want to try new cranks. Not what you wanted to hear i’m sure.

First, try making a extender for your wrench/allen key, so you can apply more torque. get a hollow tube and slot it over your wrench to give it extra leverage. loosen the pinch first, then give the main bolt a heave, or go the your lbs/garage ad get someone there to do it up with their torque wrench.

A really really long shot, but are you sure it’s not the pedels? Dodgy pedels might give you the feeling of dodgy cranks…

the more worn the hub becomes, the faster it will wear. There is no way to repair a worn hub. Eventually the hub will round out completely, and the hub will be junk.

Hubs do wear natural, but not very quickly. Always check the tightness of the bolts every time you ride to keep it to a minimum.