Monster big bore kit replacement cylinder head
If you purchased our 120cc monster big bore kit and need a replacement cylinder head with valves installed, here ya go! This will only work on a QMB139 engine.
intake valve: 21.5mm
exhaust valve: 18.9mm
intake port: 24mm
exhaust port: 22mm
valce length 62.3mm ( works with 64mm valve cam tower)