I've forgotten what causes "Throttle Flutter" not happening at high rpm...but around 3 to 3 & half thousand rpm in top gear,is it rich,is it lean,or am I looking for an air leak some where ? Does not appear to be affecting performance as yet,it's not constant..just the initial use of the throttle,then its gone ! PS YES I have played with the air screws lately,,,if anything I've made things a little richer,probably turned the screws out a shade over 3 quarters of a complete turn.! These are the vacuum type carbs
Cheers,
Did you fit the slightly smaller air corrector jets into the carb bell mouths, if not, it sounds like you are talking about the surging issue.
In the BS40s they are mixture screws and not air screws, they are very sensitive to adjustment, but in these cases fiddling with them will not cure the surging issue.
You need to take a look at Suzuki service bulletin 36, note they show a 0.8 and 0.9 corrector jet but theres also a 0.7 available. Most bikes required a 0.8 to be fitted.
Hi Allan,sorry mate I meant mixture screws,no the dreaded surging problem I've sorted,thanks to Baz's video over at "the kettle clinic" Idles nicely at 1,000rpm,very little surging or bucking on a closed throttle,I have since re adjusted the mixture screws back to approx 3 quarters of a turn out,have yet to road test...see how it goes at the weekend
Cheers,
I've forgotten what causes "Throttle Flutter" not happening at high rpm...but around 3 to 3 & half thousand rpm in top gear,is it rich,is it lean,or am I looking for an air leak some where ? Does not appear to be affecting performance as yet,it's not constant..just the initial use of the throttle,then its gone ! 
PS YES I have played with the air screws lately,,,if anything I've made things a little richer,probably turned the screws out a shade over 3 quarters of a complete turn.! These are the vacuum type carbs 
Hi Allan,sorry mate I meant mixture screws,no the dreaded surging problem I've sorted,thanks to Baz's video over at "the kettle clinic" Idles nicely at 1,000rpm,very little surging or bucking on a closed throttle,I have since re adjusted the mixture screws back to approx 3 quarters of a turn out,have yet to road test...see how it goes at the weekend 