Blue Line GY6 125/150cc Long Case Engine Assembly Kit

Description

Simplify your next engine build with the Blue Line GY6 Long Case Engine Assembly Kit. Designed for 125cc and 150cc GY6 scooters using a long-case belt configuration (12″–14″ wheels), this OEM-equivalent engine case kit comes with the most difficult work already done — bearings and rubber isolation buffers are professionally pressed in at the factory, saving you time and specialized tool costs.

Important: This case uses a 54mm cylinder head stud spacing. Verify your engine’s stud spacing before ordering. This case is not compatible with QMK-based engines (161QMK / 1P61QMK).

Model Compatibility

Compatible with 157QMJ / 152QMI-based engines (125cc / 150cc) with 54mm head stud spacing:

• Engine codes: 157QMJ, 1P57QMJ, YN1P57QMJ, JJ157QMJ, BN157QMJ
• Engine codes: 152QMI, 1P52FMI, 154FMI
• Fits long-case GY6 platforms with 12″–14″ wheels

Key Features

• Ready to Build: Crankcase bearings and rubber engine isolation buffers pre-installed at the factory.
• 54mm Head Stud Spacing: Correct for 157QMJ / 152QMI engines — not compatible with QMK engines.
• Long Case Design: Fits 125/150cc scooters with long-case belt configuration (12″–14″ wheels).
• Complete Kit: Includes left and right crankcase halves, 4 cylinder head studs, rubber engine mount buffers, and breather hose.
• OEM Equivalent: Blue Line direct-fit replacement when OEM parts are unavailable or cost-prohibitive.

Technical Specifications

• Engine Compatibility: 157QMJ / 152QMI (125cc / 150cc / 169cc)
• Head Stud Spacing: 54mm
• Case Type: Long case (fits 12″–14″ wheels)
• Material: Die-cast aluminum alloy
• Includes: Left & right crankcase halves, 4 head studs, rubber buffers, breather hose, hardware
• Bearings: Factory pre-installed
• Dimensions: 20″ L x 12″ W x 5″ H

California Prop 65 Warning: www.p65warnings.ca.gov