Glixal GY6 Cylinder Head Assembly 57.4mm — 150cc Conversion, Non‑EGR with Valves Set

Glixal's GY6 57.4mm cylinder head assembly is a non‑EGR replacement that converts compatible GY6 125cc engines to 150cc performance with a complete valves set.

If you need a direct-fit replacement or an upgrade path from a 125cc to a full 150cc GY6-style engine, this cylinder head assembly from Glixal provides the larger combustion chamber, matching valve dimensions, and a 4-bolt valve cover interface. It is engineered for most Chinese-made scooters and ATVs using the GY6 150cc 4-stroke platform and is supplied without an EGR port to suit non-EGR conversions and many aftermarket valve covers.

Will this cylinder head fit my GY6 engine?

The Glixal head fits GY6 125cc–150cc engines that use a 60mm tall head, a 76mm bolt pattern, and a 4-bolt valve cover. Confirm your current head dimensions and bolt layout before ordering to ensure bolt-hole alignment and correct valve cover fitment.

• Compatibility: GY6 125cc to 150cc engines with 60mm tall head
• Bolt pattern: 76mm bolt spacing
• Valve cover: requires a 4-bolt valve cover
• Fits many models: JONWAY, JMSTAR, ROKETA, SUNL, TAOTAO, and others

What are the valve and chamber specifications?

This assembly ships with matched intake and exhaust valves sized for the 57.4mm combustion chamber to promote reliable seating and predictable performance. Valve lengths and diameters are provided so you can verify rocker arm clearance, spring fitment, and any cam timing considerations.

• Combustion chamber diameter: 57.4mm
• Intake valve: 28mm OD, 66mm length
• Exhaust valve: 23mm OD, 65.5mm length
• Non‑EGR design: no EGR port in the head

How does this head support a 125cc-to-150cc upgrade?

By increasing the combustion chamber diameter and using valve sizes matched to a 150cc GY6 spec, the head accommodates the larger bore required for 150cc displacement. When combined with a compatible cylinder and piston set, this head helps complete the conversion while retaining standard valve geometry.

• Designed for larger bore dimensions used in 150cc conversions
• Maintains stock-style valve dimensions for compatibility
• Non-EGR layout simplifies retrofits on older 125cc engines
• Complete valves set included for direct installation

What should I check before installation?

Inspect bolt pattern alignment, valve clearance, and valve cover compatibility before fitting the head. You may need a compatible gasket set, appropriate torque values, and possibly adjustments to carburetion or fueling after the upgrade.

• Verify 76mm bolt pattern and 60mm head height
• Confirm your valve cover is a 4-bolt design or obtain the correct cover
• Use new head gasket and follow proper torque sequence
• Re-tune carburetor/fuel mapping after displacement change

Who is this for: Motorcyclists, scooter owners, and small-ATV enthusiasts who run GY6-style engines and seek a reliable non-EGR cylinder head for repairs or to convert a 125cc small-displacement engine to the 150cc specification. This product is aimed at DIY mechanics and professional shops familiar with GY6 platforms and standard cylinder-head installation procedures.