Apologies if this duplicates posts by others; I confess I did not go back through the whole archive.
Lately my scoot has been rough off the starting line, with the clutch grabbing somewhat violently a couple of times before getting moving. Worse at low rpm; I had to grab a handful to get going without drama. The best way I can describe the feel was like being in the car with a teenager learning to drive a stick. I mentioned this to a buddy who used to own a Vespa dealership and he told me my roller weights had flat spots. He also told me that as long as I was replacing the weights I should put a new belt on.
Today I spent a good three hours wrestling with the tupperware and the fasteners around the air filter and the drive case. Splitting the case involved a mallet and a pry bar as the gasket had fused to both sides of the case. And once inside I needed a decent impact driver to remove the variator nut.
Sure enough, the rollers had assymetric wear, aka "flat spots." Visible but subtle in appearance, but immediately evident when rolling them on a flat surface.
The ramps on the inside of the variator had corresponding wear marks showing the weights had been sliding in places and not rolling.
As suggested, I also replaced the belt, which hardly looked worn. Slightly different part number, with the difference being, I think, some Kevlar.
Buttoned it all back up, losing only one locking tab on the fenderr skirt, and sure enough, the problem went away entirely. I've been noticing some loss of top speed lately, too, and I am hoping that, too, will have improved, but I'm in Key West atm and I can't really get it up to full speed here.
Anyway, I hope someone finds this useful.
