drive train clunk

[gothbiker]

my 1150 gs had developed a clunk, it happens when pulling away in first, well all through the gears, even in top if you back off, then wind the power on, theres a clunk, with the bike parked the bike moves about 6 inches forwards then back taking up slop in the drive train, ive tried it in 4th and 5th aswell, it only moves the same distance as first gear, so would this mean the cluth and input splines will be ok? ive pulled the boot off the swingarm and there isnt any rubber of metal debris, the bike is also vibrating a bit, so? would there be any ideas? ujs on the drive shaft? final drive? or hopefully not the gear box, if anybody had any advice it would be great, im based in liverpool, but am up in clevleys by blackpool at the weekend if anybody is around?
thanks dj

 

[alphadog]

my first thought would be uj, but must say I haven't seen many posts about that particular problem.have a peek at you tube,while you wait for the clever guys on here.

 

[Slipperyeel]

I don't get the bit about the bike moving forward 6" then back? Can you explain better. If it's moving how can it be taking up slack? That would suggest no slack?!

Clearly I haven't understood ;-)



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[tuftywhite]

Could be the splines on your final drive.

I had mine fixed by Mikeyboy of this parish.

 

[flatdog]

How many miles, it may be a combination of spline/uj/bevel box/ gearbox wear.

What ever it is if you put it in gear and can roll the bike back a forwards that amount before the drive chain engages thats a little excessive.

IMO The selection of different gears will change the rate of turn within the gearbox etc so may be a red herring.

 

[gothbiker]

The bike has 42 thousand miles, it's been serviced properly, the free play/slack is when it's stationery In gear pushing the bike, I used a few marks to measure it,
The whole bike feels like it's vibrating, I only discovered when I rode my friends bike.
Thanks for all the advice so far. Dj

 

[Welshman]

The bike has 42 thousand miles, it's been serviced properly, the free play/slack is when it's stationery In gear pushing the bike, I used a few marks to measure it,
The whole bike feels like it's vibrating, I only discovered when I rode my friends bike.
Thanks for all the advice so far. Dj

Have the drive shaft checked is my best advice, but its very low mileage for that, has the rear bevel drive been off recently? If you dont smack the UJ it doesnt seat on the circlip?

 

[gothbiker]

Thanks for the advice, the bevel has never been off, think I will have to strip it down next week, thanks for the advice so far.

 

[monkeyboy]

Have you put it on the centre stand in gear and rotated the rear wheel. The resistance to movement should be constant if everything is tight. If it's really loose then starts to resist there is clearly a fault. I've had my UJ go tits and it made a weird noise even when wheeling the bike in neutral as the UJ still rotates. It did have a lot of drivetrain slack and shunt though like you. Splines are solid / engaged or they're not - there is no in between so as you have drive then I wouldn't think it's the input splines. Could be a shagged rubber damper in the upper UJ but it doesn't sound like it. I would try the wheel first.

 

[gothbiker]

Just had a good look over the bike, it looks like it's the rear if the gearbox and front section of the propshaft, any advice on stripping it down? Thanks for the help so far, hopefully it's the propshaft and not the gearbox!


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[warmshed]

This might help http://www.youtube.com/watch?v=L0_j8SuiFQI

 

[gothbiker]

so far i have had the rear diff off, all splines seem ok, I have just taken the swingarm off, the uj is perfect, you can feel a lot of free play in the box, so tomorrow i will know if its the output shaft splines or which i suspect I will have to remove the gearbox, has anybody had this amount of freeplay? where did you find the problem was, any advice if to rebuild or just buy a replacement box secondhand? if i do decide to rebuild is it best replacing all the bearings? any other jobs or parts to replace when its in parts apart from the clutch? thanks dj

 

[gothbiker]

Propshaft off, no wear in the splines, play in the gearbox, so before I strip it down at the weekend, any ideas, I think it's the input shaft, mate says broken spring on the clutch, output shaft turns ok smooth aswell.


From a fuckin iphone....

 

[cele0001]

There are no springs in the clutch. There is a dampener of sorts on the input shaft but from what you are saying it feels like inputs splines on the clutch are gonne and probably input shaft.
Take the starter off, which you have to do anyway if you are taking the gearbox off, ziptie the clutch handle, and check the play on the clutch plate.
Let me see if I can find that video.

 

[Steptoe]

m with the bike parked the bike moves about 6 inches forwards then back taking up slop in the drive train,

This is perfectly normal.

 

[a2zworks]

Sounds like mechanical Hypochondriac to me......
You'd worry sheep, ride the thing don't mother it.