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View Full Version : Have you ever run your bike up through the gears while on it's centre stand?



Muppet
06-08-05, 21:57
A strange question it may be, but stay with me on this one for a bit, I need your help.

Could someone with an 1100 (preferebaly) or 1150 stick their bike on itís centre stand and run it up through the gears. Make sure the front endís weighed down of course! Can you listen for any rattle type noises, like a worn bearing, particularly on the overrun in higher gears.

Having rebuilt my bike after my gearbox woes (http://www.ukgser.com/forums/showthread.php?t=49630&page=3), I now have a rather nasty noise coming from that area. Least I think it is, itís hard to identify.

When the bike is on itís centre stand, engine running and I take it up through the gears, it gets noisier the higher the gear Iím in. Itís a bearing type Ďrattleí thatís quite loud on the overrun in 5th, but goes when I accelerate. Itís slightly less noisy the lower down through the box I go, in first itís not really that noticeable above all the other noises.

I havenít had a proper chance to take it on a road test yet, just a quick bimble up and down the lane (well, farm track) where my workshop is and it didnít seem to bad. Couldnít get it into 5th though (not enough space). To try and eliminate things, hereís what Iíve done when I rebuilt it all.

At first I swapped gearboxes with another unit, to do this though I had to swap front covers (the clutch end) from my gearbox to the 2nd unit. However, this 2nd unit prved to be faulty, so having got my original box repaired (it was a broken lug) I proceeded to swap front cover plates back. Then it was a question of refitting everything (after sticking in a new clutch) and seeing what happened.

My thoughts are that maybe I buggered something up in removing and re-fitting of the front cover plate, although I was careful and hopefully replaced all the shims in the right places Ė there was only a few.) Itís possible I might have disturbed an end-float bearing on one of the shafts, it does sound like a bearing noise, but it sounds as though itís coming from the shaft. Is it possible Iíve disturbed the drive shaft output bearing in the box? I really hope not but it seems quite likely. Either that or a bearing is spinning in itís mounting Ė which is also not good!

Your ideas, comments or thoughts would be much appreciated.

Den
06-08-05, 22:22
They all make that noise when you do that. I was advised not to run it through the gears on the centrestand as it puts the uni joints at weird angles.

Spout
06-08-05, 22:51
" it gets noisier the higher the gear Iím in"

So it sounds more driveshaft speed than engine speed related.
Somewhere between the layshaft and rear hub then.

It's probably your UJs screaming in agony over the angle you're running them through! Try taking the rear wheel off (and rear shock?) and block up the rear hub so the shaft has a straight run. Still noisy?

Muppet
07-08-05, 08:57
Ok, thanks Den and Spout.

I tried it without the rear drive on (much less load and not such an extreme angle) by holding onto the end of the shaft while running it up and the noise pretty much disappeared. Guess it's down to the extreme angle then, I'll take it on a decent road test today and see what happens.

Number 6
07-08-05, 16:55
A strange question it may be, but stay with me on this one for a bit, I need your help.

Could someone with an 1100 (preferebaly) or 1150 stick their bike on itís centre stand and run it up through the gears. Make sure the front endís weighed down of course! Can you listen for any rattle type noises, like a worn bearing, particularly on the overrun in higher gears.

.
You shouldn't do that :eek: Engines and transmissions are designed to run under load, they need to be driving against a resistance otherwise everything just rattles backwards and forwards due to backlash. It WILL be noisy under these circumstances. On the overrun it will be even worse, it won't know if it's coming or going.