1990 GS Making Clunking Noise

[Adam Fraser]

I have a '90 GS that makes a clunking noise when i am going slow in first gear and give the throttle a hard bump.  It is just one clunk and seems to be coming from the chain side of the engine (at least sure it is in the bottom end).  This doesnt seem to do it when I am riding along normally just when I am off the throttle in 1st and then suddenly get back on it.  Chain seems good, sprockets also.  Any help would be appreciated.  BTW.... Anyone know the proper chain slack in inches for this bike.

Thanks, Adam

[Richard UK]

Sounds like chain 'lash' - just the slack in the chain being taken up suddenly.

[JamesG]

With the bike on its centerstand and the swingarm unloaded I tighten it until there is about an inch of play in the chain mid way between the sprocket and the heel guard.  The chain tightens up a bit when you are sitting on it.

To loose is better than to tight!

[Adam Fraser]

Thanks, thats what I thought it was too, but the chain seems to be right.  Ill check for the 1" of play on centerstand.

[JamesG]

Why you are checking, take the cover off the front sprocket and make sure nothing is wrong in there.