Engine Noise: Cam Chain or Valves?

[sam000lee]

When cruising, typically in 4th or 5th gear (I don't really notice it it in 1st, 2nd or 3rd) I have been noticing a kind of slapping noise coming from the engine. It happens while 'maintaining speed' and so either letting up on the throttle or giving it a little more makes the noise go away. I should also say that if I'm going over a bit of bumpy road slowly I hear the same noise which leads me to think maybe the cam chain tensioner isn't working correctly and the chain is wiggling around a bit.

I need to check my valves anyway, but does this sound like it could be the tensioner?
Bike is a 1981 GS450
Thanks in advance.

[tom203]

So you are sure its not the drive chain?

Ok,check valve clearances- when cover is off you'll sorta get idea if your chain has excessive slack. But best to remove tensioner, reset, and reinstall correctly so you are 100% sure. Good time to check camshaft to crankshaft timing too.

[sam000lee]

This is embarrassing but it was the drive chain! I feel very stupid.

[tom203]

This is embarrassing but it was the drive chain! I feel very stupid.

To atone for your sins,check valve clearances.Get oem cam cover gasket and a set of feeler gauges that include a .0015 inch blade, (yes .0015 inch, not .010)

[tkent02]

Or do it right with metric ones.

[tom203]

Or do it right with metric ones.

He's in Boston, so no sense confusing him with metric system.

[tkent02]

He didn't mention being a moron from Boston.

[tom203]

I hope he notices your fascination with "L" models and doesn't get distracted from his valve adjust mission.