Step 2
Installation

Detailed installation of 139qmb big bore kit.

I'm going to show you in detail how to install a 139qmb big bore kit.

If you want to maximize the power and speed of your gy6 50cc 139qmb scooter this big bore kit has the largest displacement, largest valves and ports and is the highest quality kit available for the money.

#SA88

52mm Domed Piston
52mm Bore
23mm Intake Valve
20mm Exhaust Valve
64mm Valves

Useful for the installation of any 139qmb big bore kit