thanks baddi
I was trying to flush out the problem this weekend so put in brand new rollers (6g) and brand new good quality belt.
No improvement. In fact I guess stock must be 6.5g as I'm not revving higher earlier with no additional acceleration/power.
carb adjustment...i have an #82 jet, but must admit have never adjusted the float height. Didn't really understand the physics behind it but maybe should check.
Battery is new and fully charged, and spark plug is new, plus I replaced the ht lead less than 6 months ago so I don't think ignition is the problem.
That said every time I change the spark plug it is black black black, covered in carbon which is interesting. I change it nearly once every 2 months!
Now i don't want to get into an argument on stock parts, their funtions and the importance of their forces, with the guys from other countries again, so ill stick to what i've measured myself.
I've been told many times by other danes, that the roller weight is 7g here in Denmark, to be able to gear out at the rpm which the CDI are restricted to, so here a couple of days i measured some rollers. Unfortunately i haven't got any new stock rollers, so i measured some old worn down ones, where the weight said that 3 rollers weighed 19g (on a kichen scale, only shows whole grams), which suggest that the rollers are 6,5 or 7g as stock.
I've had most luck with 6g and 6,5g rollers where the 6,5g was achieved by mixing 7 and 6g rollers. This is approximately the same as having 6 6,5g rollers, but have one disadvantage: The heavier rollers will push at a higher force, being worn down easylier, as seen on the picture below, where the stock rollers in the bottom have driven 3000 km, where 1500 where mixed rollers, and the malossi roller on top have driven 4000, where 1500 where mixed rollers.
About the spark plug being black all the time, i have the same problem, but streido came with a possible solution:
As a general rule its a 80 jet stock, 82 jet deslrestricted, and 88 for an open air filter but im sure you prob know that most scoots vary slightly?
I dont swap my jets for winter here in Scotland, maybe i should?. I just run the 82 all yr on mine?
Comes out ok on plug for me no leaness or richness, tho its always a little slower in the cold or wet, 3-5mph sometimes.
Had a similair issue a while back where i couldnt get the plug right, was way too rich then added more air in and got better but still had a sooty plug a bit. Found out eventually i had slighlty too much engine oil in cos i filled it on a slope, drained a little off and refitted the 82 jet put back on my stock air box and it was perfect again.