GY6 High-RPM Racing Valve Set - 28/23mm

GY6 High-RPM Racing Valve Set for GY6 125cc, 150cc, and 171cc Engines

This racing valve set suits GY6 125cc, 150cc, and 171cc engines and is aimed at riders who want a noticeable boost in performance. It should deliver smoother running and stronger acceleration at higher revs. As one of the GY6 scooter parts in our range, it addresses frequent problems such as rough idling and loss of compression. Fit these valves to get a more responsive and capable engine.

Precision-Lapped Seats for Reliable Sealing

Each valve has precision-lapped seats that create a full 360° seal. This design cuts down on compression loss, which helps the engine idle more steadily. The valves also tolerate high heat, which reduces mushrooming and carbon build-up that often affect factory valves under demanding use.

Engine Compatibility

The valves are built for high-flow setups and can handle RPMs above 10,000. The intake valve measures 27.8mm and the exhaust valve measures 22.9mm, so they work with a range of big bore kits. Before final installation, seat the new valves properly in the cylinder head using fine-grit grinding compound to achieve a tight seal.

Specifications

• Intake Valve (IN): 27.8mm OD | 65.75mm height | 5.0mm stem
• Exhaust Valve (EX): 22.9mm OD | 65.3mm height | 5.0mm stem
• OEM Part Number: 665C13GY628LL
• Origin: Made in Taiwan
• Fits: GY6 150cc (157QMJ) engine

Fitment

Fits:

• GY6 150cc (157QMJ)

Where it goes: part #8 on the camshaft and valve diagram for the GY6 150cc (157QMJ).

Shop more: GY6 Scooter Parts · Chinese Scooter Parts · Scooter Cylinder Heads & Valves · Scooter Parts