Description
If you’re running a Big Twin and want real displacement gains without a full engine rebuild, the S&S Cycle 1250cc Piston Kit delivers measurable power increases through proven engineering. These cast flat-topped pistons unlock an extra 50cc of displacement while maintaining the 10.3:1 compression ratio that works with both stock and performance cylinder heads. Whether you’re tuning for the street or the strip, this is a bolt-on path to increased torque and horsepower.
- Displacement: 883cc to 1250cc
- Compression ratio: 10.3:1
- Piston design: Cast flat-top
- Bore size: 3-9/16″
- Compatible heads: Stock or S&S CNC ported
- Application: 1984–’99 HD Big Twins
- 1200cc cylinders: Direct fit
- 1986–’2003 883cc cylinders: Requires boring
- 2004–’16 883cc cylinders: Not compatible
- Installation: Bolt-on with proper machine work
- Material: Cast iron construction
- MPN: 106-4416








