Description
A worn or damaged top-end directly kills engine performance and reliability—and a full piston kit replacement is the most cost-effective way to restore your XR400R or TRX400 to factory specs or beyond. Wiseco’s forged pistons are engineered for the demands of trail riding and racing, handling sustained high RPMs and aggressive throttle inputs without detonation or premature wear. This complete kit includes everything needed for a proper top-end rebuild, eliminating guesswork and ensuring all components work together as intended.
- Forged high-silicone construction
- 10:1 compression ratio
- 88mm bore diameter
- Includes forged piston
- Piston rings included
- Wrist pins included
- Circlips included
- Top-end gasket set
- Reduced thermal expansion
- Compatible: XR400R 1996–2004
- Compatible: TRX400EX 1999–2008
- Compatible: TRX400X 2009–2014
- Wiseco rings required
- Bolt-on installation
- MPN: PK1035
