gearbox noise

[scribbles]

i've recently had my gearbox rebuilt with the circlip mod on my r100gs, it blew the output bearing and smashed the casing where the driveshaft boot is. i got it fixed by scrimmenger and put it back on myself. its fine when driving but when i coast slowly with the clutch in it clatters quite loudly. like a bag of rusty bolts in a tumble drier. no not that bad at all but i didnt have it before. any ideas? is there something i may have done wrong putting it on or could it be my driveshafts slopping around? not had the shaft go before so dont know what that sounds like although im pretty sure it isnt the original one and its got about 45k on the clock so i wouldnt have thought its done many miles.

 

[Voyager]

If Steve Scrimminger re-built your box you can be sure its OK

If the rear bearing collapsed and the output shaft was thrashing about enough to break the rear gearbox case you have probably knackered one or both UJs on the propshaft. So:

Undo the rubber boot at the gearbox end of the leg and peel it back.

Hold the gearbox output flange tight and then move the rear wheel back and forth. You will probably see / feel / hear movement in the joints.

If the shaft is OK the noise could be coming from the clutch plate. Were you doing something extreme when the gearbox failed ??

I'm thinking that it might be the clutch assembly working loose or very worn splines in the centre of the friction plate.

Its unlikely that you have done anything wrong when putting the gearbox back in or it wouldn't be working at all (unless you forgot to put oil in it ).

Keep us informed; its useful to know where noises come from .

Bob.

 

[scribbles]

Reviving an old thread! My bikes been laid up for a while but I've just been giving a bit of a refresh. I wish I'd read this this before because I could only remember the comments about checking the drive shaft not the clutch. I would have had the box out otherwise to check. I've had the shaft out and checked it, it seems fine but hard to tell if theres play or the joints are just moving. I put it all back together making sure the swing arm was completely central and everything was properly set up. The noise is still there when rolling in neutral or with no engine breaking or throttle. I then pulled the clutch in and the noise went. I assume this rules out the drive shaft and suggests something on the input shaft or something in the clutch. There was no noise from the box or clutch running up to my gearbox blowing up. would this suggest it's something not set up inside the gearbox thats rattling? any idea's would be much appreciated.

 

[Voyager]

The noise is still there when rolling in neutral or with no engine breaking or throttle. I then pulled the clutch in and the noise went. I assume this rules out the drive shaft and suggests something on the input shaft or something in the clutch. There was no noise from the box or clutch running up to my gearbox blowing up. would this suggest it's something not set up inside the gearbox thats rattling? any idea's would be much appreciated.

I would rule out the gearbox. You have only done a few miles since Steve Scrimminger built it and it will be fine.

Even if the shock absorber spring had broken I can't see that it would make that much noise.

My money is on the clutch being faulty. It only takes an hour to remove the gearbox so whip it out and strip the clutch out.

Then show us the pictures .

Bob.

 

[scribbles]

I would rule out the gearbox. You have only done a few miles since Steve Scrimminger built it and it will be fine.

Even if the shock absorber spring had broken I can't see that it would make that much noise.

My money is on the clutch being faulty. It only takes an hour to remove the gearbox so whip it out and strip the clutch out.

Then show us the pictures .

Bob.

Just got it all back together. Oh well, I'm off to remove it now. I'll report back.

 

[scribbles]

I took the box out. took about an hour. I took the drain plug out and the magnet was covered in fillings and the oil looked all sparkly with bits of metal in I looked at the clutch and it all looked fine but I didn't feel like disassembling it. What should I check on the clutch?
I don't really know what to do next with the box. It seems to work fine but when rolling at idle or first and second with without throttle or engine breaking it makes a clattering noise. I did notice when you rotate the output shaft and hold the input splines it has roughly between an eighth and a fifth of a turn free play in all gears. Is this normal? I can imagine that making it rattle as the shaft takes up the free play:nena
Part of me is tempted to put it back and run it into the ground.
Another thing I noticed when i took the shaft out that the gear linkage connects, the end was quite worn where it has a quarter round machined out. Not sure what this indicates. Any help much appreciated.

 

[Garry H]

There is no point in running the box
It is obviously shot
It should be no problem to see what has gone wrong with it in the state you discribe it if you take it apart
I have moded boxes and fitted curclips in the past i have rebuilt without any problems at all
There are peole about who think they know how to rebuild a gearbox but don't
Steve Scrimminger knows his stuff...
Give it to someone who knows what they are doing

 

[cookie]

Why not have a chat with mr scriminger?

 

[DrFarkoff]

Why not have a chat with mr scriminger?

Plus one and Don;t run it Sparkling things in oil is bad doo doo!

 

[Voyager]

I took the drain plug out and the magnet was covered in fillings and the oil looked all sparkly with bits of metal in I looked at the clutch and it all looked fine but I didn't feel like disassembling it. What should I check on the clutch?
I don't really know what to do next with the box. It seems to work fine but when rolling at idle or first and second with without throttle or engine breaking it makes a clattering noise. I did notice when you rotate the output shaft and hold the input splines it has roughly between an eighth and a fifth of a turn free play in all gears. Is this normal? I can imagine that making it rattle as the shaft takes up the free play

Well, I'm surprised.

Ignore the clutch.

If the box has only done a few miles, and you haven't run it without oil or abused it, I think you should take it back to Mr Scrimminger and let him investigate.

Let us know the outcome as it all adds to the knowledge base .

Bob.