Hallo I just fit a new Polini crank on my Rally 50 to go with a pm x-tech,black dallorto 21, stage6 reed valve and yasuni R,it is running fine but when I stop I am experiencing for few seconds, after realising the throttle,a little surge in revs. Any idea what could it be? Thanks Alex
sounds like an air leak or sticking throttle cable. Spray some carb cleaner about around the intake...if the revs rise, its sucking air in somewhere
"If the carb is running too rich, the engine tone will deepen when you go to full throttle. Spark plugs with blacken quickly., the engine will return very poor fuel economy and appear as though it's going fast if you ease off the throttle very slight. So in terms of jetting, go down in size one at a time until this annoying little habit goes away." from minors carb guide in the guide section you will need to re-jet after fitting them parts and change the rollers+ clutch spring
