All of a sudden I can't get past 70 mph and it stalls when ever I'm on idle for at least 10 secs, so every traffic light I'm having to control the revs.

It is restricted so normal my max is about 90mph. Going to get Dyno tuned once sorted.

Thanks.
Ricky

Sounds like your carbs need a clean/o-rings and has done since you had it, mine will show 110 on speedo in 6th at 11k rpm im 13 stone. Guy on here sells the o-rings £11 a set variablevalvessuck is his name i think, goodluck with your bike

p.s forgot to note my bike is also on the 33bhp washers ^.^

Before you start stripping the carbs i'd be looking at simple stuff like the plugs first.

its running on 3 plugs only? i ran on 3cylinders before. same thing.