Engine rattle-ish

[Turambur]

Hey fella's, I've been working on my 1980 GS850 for about 5 months now and I've cleaned the carbs, gotten new air intake boots/seals, filters, oil change and tune up, battery and have reconected the head lights and installed turn signals. I took it to a mechanic who said the bike looks like it had been set up for the drag strip and every thing seemed to be in exceptional mechanical order. (my bike looks like it's survived WW3 as far as paint and cosmetics) My question is this, I've pretty much just started riding it and I can hear a separate noise (from the engine) that sounded like a wheel with copper brushes just spinning and the copper brushes were rubbing against something. I thought that it might be the stator, but the last time I rode the bike the noise seemed to be a bit more loud and chain-like, it also seemed to becoming from behind the headers.. Any ideas? (I'm sorry for the vague descriptions but it's the best I can do to explain the noise)

Any help is MUCH appreciated!

[NICK!]

Might be the cam chain. Those tensioners can back up and let the chain make noise. Take the jam screw and nut out of the tensioner, turn the motor over slowly (or have someone else do it if its on the wrong side) and watch inside the hole for the farthest in the plunger goes and lock it up there with the jam screw and snug the nut. Ride it and see if the noise is gone. If so you can leave it as is you'll just have to adjust it every now and then by redoing the procedure. That or replace the tensioner.

[Turambur]

So I need to Take the motor out of my bike to get to the cam-chain?

[NICK!]

No, it may be the cam chain tensioner backing up and letting the cam chain have too much slack and that might be what your hearing. The nut and screw (jam screw) are numbers 17 & 19 below.

[Turambur]

Excellent. I'll print this out and compare it to my bike manual so I can check this out. Thank you, I'll let you know what I find out.

[bwringer]

It's VERY common to find that clueless mechanics have tightened cam chain tensioner set screws all the way instead of leaving them 1/2 turn out so the tensioner pushrod can move.

Instructions for installing new seals and resetting here:

http://bwringer.com/gs/camchaintens.html

[Turambur]

Wow! That really helps alot! Thank you. I'll set to work on it Monday and let y'all know how it goes.

[NICK!]

bwringer makes a good point. The tensioner could be locked up now, the last guy might have tightened the jam screw and left it that way. If the jam screw is tight after you loosen the nut, loosen the jam screw and give it half a turn back or so and tighten the nut. Start the engine and see if the noise is gone. This way the tensioner can act automaticly as it was designed to do.

[Turambur]

Excellent.

[chef1366]

If that's not it the GS line have very noisy clutch baskets.

[brew]

I have an 81 gs450 that i keep hearing the same noise i think, i have misplaced my manual for the thing at the moment though. Im assuming that this is the same problem as above, but do i fix it the same way? or are the 450's different?