HI

I have a YS 91 FZ that I am having some problems with. The motor has a about 4 gallons of fuel through it, but will just not run at low throttle without quitting.

As the instructions I have set the high speed needle, and after much fiddling cannot get the low end to run reliably.

I have noticed that after reducing the throttle from full to idle, the engine ticks over for a few seconds then picks up rpm and quits.

Can anyone tell me if it is normal for there to be a lot of air bubbles in the tube that goes from the regulator to the carb ( at low throttle ).

I have read other threads about this type of engine, and although I am very familiar wth standard four storke engines this thing has me puzzeled,

Hope someone can help

Simon