
It could be due to a lean fuel mixture, poor sealing of the engine crankshaft case, or issues with the engine reed valve. Detailed reasons for a motorcycle stalling when accelerating due to insufficient fuel supply are as follows: Reasons for a lean fuel mixture: Fuel needle adjusted too low; fuel level set too low; partial blockage of the main jet; loose or leaking carburetor connection; air filter not installed; fuel supply from the tank switch is insufficient. Poor sealing of the engine crankshaft case: Failure or leakage of the crankshaft oil seal on the generator side; leakage at the joint surface of the crankshaft case; leakage at the joint surface between the crankshaft case and the cylinder or incorrect piston installation direction. Engine reed valve issues: Damaged reed valve; incorrectly installed rotary valve, causing carburetor backfire.


