Engine Stalls under load

Hi,

I can't get Bikeberry support to respond to me for help so I am reaching out to people that might have experience.

After a handful of problems, I got the replacement motor installed. It starts, runs and even idles fine but stalls as soon as the bike tire is set back on the ground.

Any ideas?

Thanks, Todd

Hard to help without seeing it and the vague description you give. Why is the rear wheel turning at idle then the engine stalls when tire is put on the ground? That sounds like 2 problems, clutch needs adjustment and idle is set too low or fuel delivery problem. At idle the wheel should not turn at all with clutch pulled in or else at a stop your going to burn the clutch up. With the clutch lever pulled in will the engine rev up and back to idle smoothly?

Sounds like clutch adjustment is way off.

bad compression
plane both head and cylinder mating surface with sandpaper and glass

too lean
raise carb needle

My motorbike had similar symptoms turning my engine into a 16:1 oil spewing monster. Try running the bike without the air cleaner even if it looks clean. After the engine clears itself of a buildup of oil from running rich; the difference my be so noticeable there may be no apparent need for a shift kit for high speed. At this point, I am considering using a very thin cotton gauze as an air filter. Just enough to keep the bugs out. At least try this before tearing down the engine or carb. Since this problem; I have switched to Opti 2 instead of Johnson outboard synthetic from Walmart. So far so good.

I agree with clutch adjustment causing it.