Universal Parts QMB139 Cylinder Head – Emissions

Universal Parts PAIR Style (Emissions) Cylinder Head for 50cc 4-stroke QMB139 engines.

PAIR is an acronym for Pulsed Secondary Air Injection System. It is an emissions control system used to lower HC and CO emissions. It works by allowing air into the exhaust flow.

• 39mm Bore
• Intake Port Diameter: 17mm
• Exhaust Port Diameter: 18mm
• Emission Control System: Pulsed Secondary Air Injection System(PAIR)