Originally Posted by
rick oxley
thanks for the repleys,when you hit the brakes you can tell it's lean,if you tune it real rich and do a standing start you can go from rich bog then hit the brakes as soon as it starts to clear out it will hang lean for about 5 seconds then start to droop down. had some help from one of the top guys same results as me try to go any where close to a race tune and it gets worse
checked every thing over today carn't find anything. could bad fuel cause this?
Don't just check the fuel line, replace it, just in case. It may have a tear that you cant see. Also make sure there isn't any fuel around the exhaust exit on the motor, if there is, replace the gasket. Same thing with the header to pipe gasket. Also, look around the area where the carb goes into the engine case, is it wet? You could have a leak there, make sure the carb is pushed all the way down into the case. Look at the area around the glowplug, is that wet? You may have a leaking head button. From you description it sounds like your bottom end is super lean, I would back off the needle a lot and see what it does.