Bonneville America Forums Forums Technical Forums General Tech Chatter/vibration in the driveline

OK y'all...HELP! I had a new cush drive installed before the LOP Rally in Jefferson TX. When I picked the bike up, I noticed a chatter or vibration as the clutch fully engaged. It almost feels like the chain is trying to climb the teeth on the sprocket. Got the bike home and made sure everything was aligned. This eased the problem but didn't take care of it entirely. I ran the bike in gear on the lift and the chain seems to jump around a bit, this also improved but didn't go away entirely after adjustment. Any ideas...new chain/sprockets, clutch issue? Any input would be appreciated.

Ride safe

How many miles you got on the chain and sprocket set?

The bike is an 03 Speedmaster with 6300 miles. I bought the bike in June with 3600 miles. Chain and sprockets are original equipment. I had the cush drive replaced at 6000 miles because it had alot of play and would make a big "clunk" when engaging the cluth to get moving and when disengaging while in 1st gear and moving at slow speed. The chatter was nonexistant until after the cush drive was replaced. I specifically asked the guys down at RPM to check the chain and sprockets while they had it apart. They said chain and sprockets were fine because they were only about half way through the available adjustment. When I got the bike the chain was definately in need of some maintenance (cleaning and lube)but didn't appear to be in bad shape. After reading the various threads here, I have realized that I don't clean and lube it often enough either, especially with my rather long gravel driveway.

Sounds like the chain is either not aligned straight on the sprockets or is too tight!!!
With bike on sidestand make sure you have about 1 inch up and down play in the chain.
If it is an alignment problem then you need to get the rear wheel off the ground so you can spin it in neutral.

Sounds like a really loose chain.

Over the last week or so I have tried different chain tensions, from tight to loose, and the problem persists. The chatter is only really evident when starting out in first gear and when rolling on the throttle at slow speeds. When watching it run on the stand, the chain pops and jumps on regular intervals, like you'd expect it to if it had a messed up link. Only thing is...I can't visually find a problem. I'm thinking at this point that I'll just order new chain and sprockets. I have been considering trying a 17 or 18 tooth up front anyway.

I once had a dealer put a tire on a Sportster and rode away with a chain that "popped and jumped at regular intervals". They had cut the chain and installed a master link and the link was extremely tight. It did manage to work itself in, but until it did, it was quite annoying.

In looking for my vibration problem I put mine on the lift and let the back wheel spin in 2nd gear and got the same result. Jumping around as you put it. I think thats probably normal on a lift tho because the tire is not hooked up and the wheel is constantly "catching up" and then slowing down as the engine cathes it again, if that makes any sense. Thats the best i can explain it, but i think thats the case.

I *think* i did this BEFORE i installed the new chain, but on the advice above i'll check out the link i put on. It's not the reaon for my problem tho because it had the vibes before the new chain.

I think you are right daz about the chain jumping because of no load on it when sitting on a stand. Mine has always done this since new. I don't have the vibration problem BKG is refering to so I would think this is not related to his problem.