NCY 61mm No-Cut GY6 Big Bore Cylinder Kit - 171cc

This NCY 61mm aluminum big bore kit gives your compatible GY6-A 125/150cc four-stroke build more displacement for a more spirited off-road ride. The 61 mm bore delivers approximately 171.3cc with the applicable crankshaft stroke. Its 62.99 mm outer cylinder skirt allows a no-case-cut installation on engine cases that accept that diameter, while aluminum construction supports efficient heat transfer.

This product is intended for off-road use only. This product is not intended for use on public roads or land.

Key Features

• More displacement: 61 mm bore for approximately 171.3cc with the applicable crankshaft stroke.
• Conditional no-case-cut fit: 62.99 mm outer cylinder skirt fits compatible case openings without machining.
• Aluminum cylinder: Supports efficient heat transfer in an air-cooled engine.
• Short-skirt piston: Reduces reciprocating mass.
• Matched kit components: Includes cylinder, piston, rings, wrist pin, clips, and gaskets.

Technical Specifications

• Brand: NCY
• Part number: 1100-1288
• Manufacturer part number: 603C02GY661
• Bore: 61 mm
• Displacement: Approximately 171.3cc with the applicable crankshaft stroke
• Outer cylinder skirt diameter: 62.99 mm
• Cylinder stud spacing: 54 mm
• Engine case: GY6-A block
• Cylinder material: Aluminum
• Starting engine applications: Compatible GY6 125/150cc four-stroke QMI/QMJ engines
• Includes: Cylinder, piston, rings, wrist pin, clips, and gaskets
• Country of origin: Taiwan

Compatibility

Does not fit Genuine Buddy 125, GY6 B-block, 161QMK, or other QMK engines.

Verify the GY6-A case, 54 mm cylinder stud spacing, 62.99 mm skirt clearance, deck height, oil passages, cylinder-head compatibility, and piston-to-valve clearance before assembly. Engine code alone does not guarantee fitment. No-case-cut installation applies only when the case opening accepts the skirt diameter.

Tuning and Installation

Increasing displacement requires fuel-system tuning. Carbureted applications generally require re-jetting; the correct jet size depends on the carburetor, intake, exhaust, elevation, and other modifications. Professional assembly, clearance checks, break-in, and tuning are recommended.

• 61mm bore produces approximately 171.3cc with the applicable crankshaft stroke
• 62.99mm outer cylinder skirt designed for compatible no-case-cut installations
• Aluminum cylinder construction supports efficient heat transfer
• Short-skirt piston reduces reciprocating mass
• Includes cylinder, piston, rings, wrist pin, clips, and gaskets

Brand: NCY; Part number: 1100-1288; MPN: 603C02GY661; Bore: 61 mm; Displacement: approximately 171.3cc with applicable crankshaft stroke; Outer cylinder skirt: 62.99 mm; Cylinder stud spacing: 54 mm; Engine case: GY6-A; Cylinder material: aluminum; Starting engines: compatible GY6 125/150cc QMI/QMJ; Codes: 157QMJ, 1P57QMJ, 152QMI, BN157QMJ; Excludes: Buddy 125, GY6 B-block, 161QMK and other QMK engines; Includes: cylinder, piston, rings, wrist pin, clips and gaskets; Origin: Taiwan; Use: off-road only

Compatible GY6-A 125/150cc QMI/QMJ engines including matching 157QMJ, 1P57QMJ, 152QMI and BN157QMJ configurations; Genuine Buddy 150 and Blur 150; select TaoTao, Wolf, Ice Bear, Bintelli, Peace Sports, ZNEN, SSR and SYM applications; select Hammerhead 150, Trailmaster 150, Yerf-Dog and Carter Talon go-karts/buggies. Excludes Buddy 125, GY6 B-block, 161QMK and other QMK engines. Verify 54 mm stud spacing, 62.99 mm skirt clearance, deck height, oil passages, head compatibility and piston-to-valve clearance.