Replace your 40mm stroke Avenger 85cc crank assembly with a new 42mm stroke crank. = 89cc Corrects the problem of short stroke wide squish current A85 engines.
Flywheels have 5 holes each for a more balanced smooth-running engine.
Conn rods made for 12mm dia. wrist pins.
Made with CCW Left hand M8-1 threads allowing OCDT use.
Comes with a copper plated 12 roller 16x12x16 wrist pin needle bearing.
