Giraffe is Delicious

Ok, now I am wondering two things. First, you see on the left side there’s a (I’m at a loss for the name) metal washer-type thing that you can screw and unscrew? It comes loose every time I ride. Is this a problem, and what can I do to fix it?

Secondly, what are closed bearings and how do I get them? The bike shop guy said I have open bearings but didn’t explain what they are or what problems they cause. Any help would be appreciated.

The metal washer-type thing is called a lockring, and it holds all the bearings and grease and axle bits together. You want it tight as you can get. Generally you’re going to want a special wrench called (surprise!) a lockring wrench. The axle is actually a standard bike part, just in a different place, so bike shops should be able to tighten this for you no problem.

I’m at a loss in terms of bearings. The bike shop guy might have meant sealed vs. unsealed pedals or something. I don’t think it’ll make that much of a difference though.

Thanks flyer

This might be the wrong answer, but if you don’t have a lockring wrench you can use a square brass drift and hit the drift on the slots (not the lockring) with a hammer. I do this successfully…but be carefull, you can damage it. I want to buy a lockring wrench but don’t know where to get one.

As said above, it looks like a normal bike bottom bracket. What they are talking about with sealed bearing is the cartridge style of bottom bracket.

Something like this: http://www.chainreactioncycles.com/Models.aspx?ModelID=12

Do you do a lot of idling? Could it be that the BB is lossening because it is going the wrong way a lot?

ulyssesnitrate9,

You should be able to upgrade your giraffe to a sealed cartridge BB (Bottom Bracket) as decent bikes have…
I’m quite sure the shell size in your case too is the standard 68mm but the axle length may vary with giraffe brand / model!
On my giraffe (2007 Nimbus 5’ CrMo) the original axle was 116mm long!
You may upgrade to any bike BB that meets the actual specs of your raffie.

For more details you may read this thread (my posts…)
http://www.unicyclist.com/forums/showthread.php?t=18428

Flaviu

Lost Sixties’ Delight, you are very correct! I do a lot of idling, so that probably is what’s going on there. Thanks for the help!

Hey Flaviu, I was kind of curious what the benefit(s) of having a sealed cartridge BB would be as opposed to a normal unsealed one? I can’t even tell if mine is currently sealed or not, because the bike shop guy asked if I wanted sealed put in last time and I said go ahead, but I never got a bill for it.

Also, I’ve now noticed my chain becomes loose only when the cranks are horizontal, but specifically only when the right pedal is back and the left one forward. Any ideas?

Thanks for your help!

It doesn’t really matter whether your BB bearings are sealed or not; if you keep the lock ring tight (use blue loctite if necessary), the bearings are pretty unlikely to fail. You’d have to replace the BB to change the bearings.

ulyssesnitrate9,

Is it a QU-AX giraffe that you have?

First, read here (between the lines) about the Bottom Bracket (BB)…
It’s good to know some basic things about main components :slight_smile:

Giraffe unicycles use a transmission system similar to fixed gear bikes. The difference is that the first use low quality / cheap components for the task.

The BB of most giraffes (including yours) is the loose bearings, axle and cups concept! This was manly designed for forward pedaling only and is poor quality realized!

When you idle you turn the pedals back and forth. The phenomenon called precession leads to the BB cones being cyclically tightened / un-tightened. This obviously will work them loose sooner or later!

http://en.wikipedia.org/wiki/Precession

OK, to prevent this you either have it reinstalled with Blue Loctite by a wise mechanic or much better upgrade it to a cartridge BB!!!

The cartridge BB (as you could see in the first link…) consists of one closed unit which contains the axle and the bearings!!! The only thing you need to do is secure it well in the frame’s BB shell. This should last very much!

You can find pretty good cartridge BBs for low money now…10-15EU!

I got a Shimano BB-UN26 (10EU) for my giraffe and it works perfectly!!!
BB shell size should be 68mm and the axle on mine is 117mm!
http://bike.shimano.com/catalog/cycle/products/component.jsp?JSESSIONID=GMK2TrVTq58Rpddm67GCqV6znfLD3Nbwbvz6QQGQNJt9K3VdrQX2!-1754928902&PRODUCT%3C%3Eprd_id=845524441771271&FOLDER%3C%3Efolder_id=2534374302039977&ASSORTMENT%3C%3East_id=1408474395181419&bmUID=1183632055047

Regarding chain tension - I’m afraid the sprocket / chainring are eccentric on your giraffe too…
read again here:
http://www.unicyclist.com/forums/showthread.php?t=18428

Hope this makes it clearer somehow,
Flaviu

See, my parents had bought the giraffe from some Schwinn bike shop a long time ago and Im pretty sure it isn’t Schwinn otherwise I’d see their giant logo on it. UA-AX? Who knows? It was made in Taiwan and has no indicator as to what the actual company was.