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My "new"bella has some "items"

Starting: 1 kick no problem
Idle: one carb dont respond to the mixture screw...carbs cleaned but not ultrasone, no airleaks between carb and engine
Low revs till 5000 not very smooth and with hiccups but no backfiring
Above 5000 perfect

Timing set with strobescope

Previous owner made a balance pipe between the 2 rubbers (at inlet head)

Did a testride 100 km ... engine stopped 3 times when closing gashandle ( sounded like using a killswitch ... but i dont have one), started again with 1 kick

Anyone a good advice ?
Could it be ignition?
Valve timing ?
Changed from S to M cam, but didnt change position of the little belt poulley

I can take parts from my other sports, but that's my last option

mantaray wrote:Idle: one carb dont respond to the mixture screw

If the idle circuit is clear, the you have the throttle stop set too high and that carb is not on its idle circuit. The throttle cables need to by synchronisied, then the throttle stops.

Timing set with strobescope

Timing at low rpm will affect idle speed. If it's retarded then you may need to wind in the throttle stops far enough to come off the idle circuit.

Previous owner made a balance pipe between the 2 rubbers (at inlet head)

A balance pipe is meant to make the engine less sensitive to carb inbalance. I run without one, blanking it off on later bikes where it was standard.

Thanks Paul.

So it is possible one carb is reacting and the other dont ?

And what about the mid-range ?any idea ?

i'll remove the balance pipe

Try checking your float heights, check your needle heights are both the same and all jets are screwed in properly.
Cheers,
Dom

yesterday i checked the valvetiming= ok
Float height is checked, when i cleaned the carbs.

Needles : i'll check them today

When cleaning the carbs i noticed that the slides are worn .


I used a set 400 dart-slides but now i see they are 40's ???

Optical they looked the same .

changed the slide in the carb(s) and everything is ok