Drivetrain vibration

[WISH1965]

I have a 90cc DRR & when I ride it down the street under acceleration it stamers, kinda chuggs, feels like it does not want to shift? At idle it runs great, it revs nice, when its on a stand and I have the cover off to view the variator & clutch it appears fine, no visible sign of the descriptions listed above, only when it has my weight on it (200lbs.) My son doesn't seem to complain or anything. Could it be my weight on it or the rear end drops too much?? My 70cc is fine when I ride it. I can't imagine it is due to me on it? Something seems amiss. I have taken the clutch apart, the variator apart, new rollers, springs, etc. all good. Nothing appears visibly wrong. Any ideas? Could a tooth or two be broken in the tranny?

[jerkyboy]

With you on it the chain might be jumping the teeth on the rear sprocket.

[WISH1965]

Mike, thanks for your thoughts. I suppose it is possible.

[xtremeatv]

my drr does the same thing when i ride it, and it is the chain jumping, took me a while to figure it out. When my kid rides it, it is fine. You could tighten up your chain but you are probably better off leaving it where it works for your kid.

[WISH1965]

it does seem to make sense. the 90cc chain was sloppy, when i got on it & the 70cc was not, which explains why the 90cc has that feeling. Thanks.

[quadscrib]

Originally posted by jerkyboy
With you on it the chain might be jumping the teeth on the rear sprocket.

Had the same issue w/ my boys 70. He NEVER had the issue. Loose chain, tensioner made it look tight. I try to stay off it too..lol