Scratchy Drive Noise?

[digitalcaptive]

There seems to be a noise comming from the "drive " area of my AT, I can only describe the noise as scratchy?????
I have ridden three different AT's One being mine and the noise seems quite loud, Another being Hudders and although his has the same noise it's much less destinctive and Wigan Chris's which appears to have no noise at all. The chain and sprockets on mine are about 2000 miles old and in good condition the rear sprocket is a Renthal Alloy jobby and all serviced by a scotoiler. The noise has been there since I've had the bike and has not gotten any worse over the 1000 miles that I have done on it.......is this noise common place? should I start getting worried....

[Wigan Chris]

just to add, the noise is mostly there under slight to medium acceleration, once the throttle is shut off the noise all but dissapears. its not very loud, but very noticeable once you know its there on the bike, and isnt audible whilst riding behind it (unlike some bikes which have very noise drive indeed)

[R0vers]

Originally Posted by Wigan Chris

just to add, the noise is mostly there under slight to medium acceleration, once the throttle is shut off the noise all but dissapears. its not very loud, but very noticeable once you know its there on the bike, and isnt audible whilst riding behind it (unlike some bikes which have very noise drive indeed)

ITS NOT AN OVERTIGHTENED CHAIN?? - OR TRY REMOVING THE FRONT SPROKET COVER TO SEE IF THATS RUBBING AGAINST THE CHAIN ITSELF??

[Wigan Chris]

if im any judge of how the chain should be on an AT id say it was plenty slack enough, i even suggested to DC that it could be a touch tighter if anything.

[digitalcaptive]

Originally Posted by R0vers

ITS NOT AN OVERTIGHTENED CHAIN?? - OR TRY REMOVING THE FRONT SPROKET COVER TO SEE IF THATS RUBBING AGAINST THE CHAIN ITSELF??

If anything r0vers the chain is a tad loose, and have had the sprocket cover off to check and all seems ok....(might just have another gander to make sure)

[African Simba]

DC, A while back I had this irritating noise with mine. I changed both sprockets and chain with original OEM. Noise went away.
I hope yours turn out to be the same..

[digitalcaptive]

Originally Posted by African Simba

DC, A while back I had this irritating noise with mine. I changed both sprockets and chain with original OEM. Noise went away.
I hope yours turn out to be the same..

I'm inclined to think along the same lines as that mate, bit reluctant to spend out just yet though as its only done 2000 miles.....suppose I can live with it, I'm gonna have to get myself an mp3 player .....that'll cure it

[Yeti]

Strictly speaking top of chain will be tight under acceleration and bottom will be tight under decceleration which might point more specifically.......or it might not!

Check the rear axle is nipped up, and pop the caliper off and check for the disc/pads catching anywhere. Check for stones wedged in anywhere they shouldn't be too. If the disc is worn and has a pronounced ridge on the circumference, although the pads will wear accordingly, any twisting will have them catching it.

Have you tried getting up to speed and pop in the clutch and kill the engine. That should give you a better idea where the sound is coming from. Also (Carefully) slip the clutch out and see if the engine braking acting on the chain makes the noise. Or pop it on a padock stand and knock it into gear.

Just a few thoughts.

[StumpyFingers]

Have you checked the movement of the front sprocket?
Is it an OEM or after market?
If it is an after market spend a few pennies on an OEM front sprocket and see if that removes the noise.

[digitalcaptive]

Thanks Yeti, a few good pointers there for me to check on