SSP-G 67mm Big Bore Cylinder Kit - GY6-B 57mm Stud Spacing

This SSP-G 67mm four-valve cylinder kit is a big-bore upgrade for compatible GY6 B-case / GY7 builds, giving you the foundation for a stronger-pulling off-road engine. A ceramic-coated cylinder helps dissipate heat and reduce friction, while the forged piston provides strength for a performance build. Pair it with a matching four-valve Cygnus-style head and the appropriate crankshaft; the nominal 232cc configuration requires a separate 66mm-stroke crankshaft.

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

Key Features

• 67mm big-bore foundation: Supports a larger-displacement engine build with the matching head and crankshaft combination.
• Ceramic-coated cylinder: Improves heat dissipation and reduces friction.
• Forged piston: Stronger and lighter than a cast piston for high-performance applications.
• Four-valve configuration: Designed for a compatible Cygnus-style four-valve cylinder head.
• B-case mounting: Requires 57mm cylinder-stud spacing.
• Included rebuild components: Cylinder, piston, rings, wrist pin, circlips, head gasket and base gasket.

Technical Specifications

• Brand: SSP-G
• Part number: 169-573
• Part type: Big-bore cylinder and piston kit
• Bore: 67mm
• Cylinder height: 76mm
• Overall height: 103.5mm
• Cylinder-stud spacing: 57mm, B-case
• Wrist pin diameter: 15mm
• Cylinder coating: Ceramic
• Piston construction: Forged
• Required cylinder head: Compatible four-valve Cygnus-style head, not included
• Nominal 232cc build: Requires a separate 66mm (+8.2mm) stroker crankshaft; displacement depends on the completed bore-and-stroke combination
• Country of origin: Taiwan

Compatibility

Engine code or long-case designation alone does not establish fitment. Confirm crankcase cylinder-opening clearance, cylinder height, wrist pin, crankshaft stroke and head compatibility before assembly. Cygnus-style describes the head design, not direct Yamaha Cygnus model fitment. The kit includes the cylinder, forged piston, rings, wrist pin, circlips, head gasket and base gasket; the cylinder head and stroker crankshaft are separate.

• Ceramic-coated cylinder for improved heat dissipation and reduced friction
• Forged piston for high-performance builds
• Requires a matching four-valve Cygnus-style cylinder head
• Nominal 232cc configuration requires a separate 66mm (+8.2mm) stroker crankshaft
• B-case application with 57mm cylinder-stud spacing; verify complete build dimensions
• Includes rings, wrist pin, circlips, head gasket and base gasket

Brand: SSP-G; Part number: 169-573; Bore: 67mm; Cylinder height: 76mm; Overall height: 103.5mm; Stud spacing: 57mm B-case; Wrist pin: 15mm; Cylinder coating: ceramic; Piston: forged; Application: compatible GY6-B/GY7/161QMK and B-case QMI152/QMJ157 builds; Required head: matching four-valve Cygnus-style, separate; Nominal 232cc configuration: separate 66mm (+8.2mm) stroker crankshaft required; Includes: cylinder, piston, rings, wrist pin, circlips, head and base gaskets; Origin: Taiwan; Use: off-road only

Compatible GY6 B-case / GY7 / 161QMK four-stroke builds; GY6 125/150cc QMI152 and QMJ157 applications only with compatible B-case configuration; requires 57mm cylinder-stud spacing and matching four-valve Cygnus-style head; verify crankcase opening, cylinder height, wrist pin and crankshaft stroke; nominal 232cc configuration requires separate 66mm (+8.2mm) stroker crankshaft; Cygnus-style is not direct Yamaha model fitment; off-road use only