Scooterotica

Ok so my Casa SS200 kit is running well once on the pipe and I’ve been clocked st 82 on the flat so it’s clearly not far off on jetting. But....if I go to wide open throttle the motor misses above 8000. If I back of a fraction it’s perfect. I’ve tried putting the choke on and it gets worse.
The set up is a 30phbh and JL3 pipe.

Someone's got to ask - what jets?

150 main jet. Av268 atomiser and 40 slide. No filter

That sounds quite rich try leaning off the main a size at a time and see if it clears.

if you haven't already fitted an auto advance , now might be the time to consider it .

At 8000 rpm it would over-advanced at a static 17 degrees . According to Webster and Broadhurst you would probably be needing as little as 14-15 degrees advance at 8-9000rpm
https://www.mbscooters.co.uk/info/mb-*- ... s+282.html

I did consider some timing control but the miss is only apparent if the throttle is wide open at high revs. Back it off a fraction and it goes away and revs happily to 9000
It’s already more conservatively jetted than RLC recommend for the set up and others have got the same set up. I suspected the needle but wanted to see if anyone had the same issue?

I’ve just put a 300 needle valve in the carb as I suspected the 200 wasn’t enough but it still sounds like a rev limiter at 8000

Hi, sorry to hijack your thread but was just wondering did you get this sorted because I'm having a similar problem on my ts 225, 30mm dellorto, with filter, 140 main,av266 atom,55 pilot, x13 tc & 300 valve jet,runs great till you get to the top of the rev range then it starts to get the same symptoms as yours, I put a 200 valve jet in which greatly improved the problem with just a slight stutter, I've got a 250 to try at some point, will let you know if it helps good luck

db67 .....a 200 float valve jet is to small , you need a 300 , what exhaust are you running ? On a standard TS1 a 140 main could be a bit to large

Hi, thanks for your reply,I'm running one of the new Ron Moss clubman exhausts, I did have a 300 valve jet in I was just trying the 200 as a sort of process of elimination, if a 140 main is too large what size would you recommend? cheers