crank moves but wheel dosent

I just put my first giraffe together today, got down the block and back, and now my sprocket moves but the wheel dosnt. The chain has good tenshion, but when i put weight on the pedal it somtimes moves the chain sprocket (top and bottom) but the wheel does not move, what has gotten loose and how do I fix it? :thinking:

Tighten up the axel bolts. It’s very disconcerting when that happens. It caused me to fall a couple of times. I just got a new savage last week. (You can see the new pics here.)

At first I thought I shouldn’t tighten the bolts very tight because it kept the wheel from spinning as freely as I thought it should. But after it loosened up and I fell twice, I cranked it down tight.

Good luck!

good job

excellent photos

looks like your doing well

Do you have pics?

Sounds like you may have a hub with a threaded sprocket and the sprocket is spinning. In proper assembly the sprocket is spun on tight and then a lockring is spun up against it to prevent it from spinning. Do you have both pieces?

You may have to dis-assemble, clean, apply loc-tite, and reassemble to get it right.

It is very dangerous to ride with a loose sprocket.

Is this problem comon? Im getting a giraffe probally tomorrow, what are the chances of it having the same problem?

Beware the loose sprocket! A sprocket that unscrews without warning can cause serious injury. If your sprocket is threaded on, and held in place with a threaded lock ring, I high recommend you do as UniBrier suggested. Take it apart, clean all grease off the threads, and reassemble as tight as you can with red (permanent) Loctite. If you don’t have the proper tool to tighten the lock-ring, either buy one or hire a bike mechanic to do it. Watch them do it. Bike mechanics do not understand the stresses unicycles get, and a lesser one may not realize you need it to be tight FOR REAL.

If it is a threaded-on sprocket, do not ride the cycle until you’ve taken care of this.

Now im going to be all scared when I put mine together.:frowning:


You’ll be more scared when you let go of the gutter.

But you’ll be fine. Just choose to ride!


is this the sprocket?



uni.bmp (359 KB)

That looks like the lock ring.

The picture you attached is the lock ring. The sprocket is the round bit with the teeth for the chain. The sprocket threads onto the hub and then the lock ring threads on. The lock ring holds the sprocket from slipping and coming unthreaded. As long as both the sprocket and lock ring don’t slip then the sprocket stays tight.

The lock ring requires a special wrench to tighten. A bike shop will have the necessary tool to tighten the lock ring.

It is very very important that the sprocket and lock ring be properly tightened. If the sprocket slips you will fall off the giraffe. The fall can be very fast and without control. Very dangerous.

Take it to a bike shop and have them put the sprocket and lock ring on using permanent high strength Loctite threadlocker. The threads should first be cleaned with Loctite primer to make sure you get the strongest possible bond. Be sure to impress upon the bike mechanic that it is very very dangerous for you if the sprocket slips and that the high strength Loctite really really is necessary. Print this bit out and make sure the bike mechanic understands.

There is a basic assembly manual at the Torker USA web site: Torker USA assembly manual (PDF file)
At the bottom of the second page are the basic instructions for assembling a giraffe. But they don’t say anything about how to tighten the sprocket and lock ring.

I’ve been thrown off my giraffe (Torker TX) several times when the pedals move without me going anywhere, is this the most likely cause? I had it down as wheelspin, but this does seem unlikely on a good tyre on pavement. Does riding backwards alot aggrevate the problem? I assume that could cause the lock ring to loosen.

Pedalling backwards will cause the sprocket to unscrew. You very likely have a loose sprocket and a loose lock ring. Take it to a bike shop and have them tighten the sprocket according to the instructions above. Have them do the Loctite too. The Loctite helps a lot.

Bike shops can be very bad at properly tightening giraffe sprockets. They don’t understand that giraffes aren’t quite exactly like track bikes. Track bikes don’t need Loctite, giraffes do.

Thanks JC.

That’s an excellent description of my two rapid descents to the pavement and very clearly explains the bruises on my hip. They didn’t feel so much like falling – which I’m used to – as like being dropped.

my bro-inlaw noticed the lock ring loose before i got back to check the site. I got a hammer, screwdriver, and locktite and used the hammer and screwdriver to push it back on and it worked perfectly, oh it feels better not having your face in the pavement.

This is one of the big differences between the Nimbus Giraffe and most others on the market, it uses a 5 bolt system to hold the sprocket on so that this situation just can not happen.


The hammer and screwdriver is one way to tighten a lockring but it’s not the best. You’ll damage the lockring and you won’t be able to get it as tight as when using a proper tool.

To tighten a lockring you use a lockring hook spanner similar to this. You’ll be able to tighten the lockring without damaging it and you’ll be able to get it tighter. Your local bike shop will be able to show you the proper size and style of lockring spanner to get.

Which is the way all giraffes should be made now. The threaded on lockring style is just not safe.

Does UDC sell the 5 bolt giraffe hub by itself? Is it using the standard spacing for a disk brake rotor for the bolts?

I need to get my Schwinn giraffe made safe. Right now it has a threaded on sprocket that is Loctited. I want to either get it welded on so it never slips or replace it with a bolted on sprocket.

JC probably already knows this, but Schwinn switched to a bolted-on sprocket around 1979 or so. Apparently they figured out the danger in a track-style hub that quickly. The 5-bolt system is probably stronger, as I sheared off one or two of my 3 bolts over the years.

Yes, any intelligently designed giraffe hub will not have a screw-on sprocket. Only the “cheap” ones…