Box of Marbles

[Guest]

Well over time (40,000 miles) my 79 GS1000 has developed quite a racket at low rpms. The noise goes away when the revs increase, but when I back off the throttle there is a nasty scraping sound.

So I put in an APE manual cam chain tensioner and made sure the cam timing is proper, which did quiet the engine.

But the marble rattle and low rpms and deceleration scraping sound still exist.

Anyone know if this is a clutch issue, and if so, what might I be looking at?

Thanks very much in advance.

[tom203]

Well over time (40,000 miles) my 79 GS1000 has developed quite a racket at low rpms. The noise goes away when the revs increase, but when I back off the throttle there is a nasty scraping sound.

So I put in an APE manual cam chain tensioner and made sure the cam timing is proper, which did quiet the engine.

But the marble rattle and low rpms and deceleration scraping sound still exist.

Anyone know if this is a clutch issue, and if so, what might I be looking at?

Thanks very much in advance.

Marbles? as in ball bearings-let's hope not! maybe your oil pump is worn out and not delivering oil at low rpm, but the scraping is bad news.

[Big T]

If you hear the marbles sound at idle, pull in your clutch lever

If the sound goes away, check the clutch hub not and see if it's loose. Then, check the springs on the back of the outer clutch hub.

Check Cliff's site for the repairs

[tpalmer1359]

Thanks. Pulling clutch makes no difference. Hopefully I'll have time to take apart the clutch next weekend and figure out what, if anything, is loose and then go from there. My first thought is loose basket springs.

[tpalmer1359]

Well over time (40,000 miles) my 79 GS1000 has developed quite a racket at low rpms. The noise goes away when the revs increase, but when I back off the throttle there is a nasty scraping sound.

So I put in an APE manual cam chain tensioner and made sure the cam timing is proper, which did quiet the engine.

But the marble rattle and low rpms and deceleration scraping sound still exist.

Anyone know if this is a clutch issue, and if so, what might I be looking at?

Thanks very much in advance.

Well I pulled the clutch hub and sure enough the larger gauge springs on the back are loose. I'm using a thick screw driver to expand all the springs and make them tight. Are there replacement springs anywhere?