Scooterotica

I have the same problem.... mines an S2 and just had my silent blocks changed but still does it... Usually occurs around 40 - 45 mph.
Just purchased some uprated BGM ones (as the ones I had replaced were the small original type) they look the business so lets hope it reduces the vibration somewhat.
I am assuming( rightly or wrongly) its because of these small block engines being uprated with bigger barrel and pistons etc etc , this must have something to do with it...please fingers crossed

let me know how you get on thanks hope it sorts it out was looking at the mb ones myself.

I had started noticing greater vibrations, again at certain speeds/revs. Firstly though of the engine mounts.
It eventually turned out to be the crank was out of balance. the two webs were misaligned.

My headset vibrates like crazy at tick over so I'm going to replace the top fork bearing with loose balls to see what effect, if any, that has.

Could also be the endplate roller bearing. Mine went and made the engine vibrate at low rpms unless the clutch was pulled in.

Well Crooky,
Just had my silent blocks replaced today with the uprated BGM 3 hole.....the vibrating has gone. Sorted

thanks pal looks like that's what I'll be getting thanks again

I think I'll go that route too as the driveside one looks off centre so must be wearing.