Description
A worn or damaged piston compromises combustion efficiency, increases blow-by, and accelerates engine wear—especially critical in 2-stroke applications where precision tolerances are unforgiving. The Wössner 8104DA restores your YZ85’s performance with a complete kit engineered for durability and consistent power delivery across the entire RPM range. OEM-equivalent or upgraded builds depend on reliable piston geometry and material quality; this kit delivers both.
Built from 4032 T6 forged aluminum alloy and finished with a permanent skirt coating, this piston minimizes friction and piston rock while maintaining the thermal stability required for aggressive riding. Every component—piston, rings, pin, and clips—is included, making this a true bolt-on solution for YZ85 owners who refuse to compromise on quality.
- Fitment: Yamaha YZ85 (2002–2025)
- Piston diameter: 47.45mm
- Material: 4032 T6 forged aluminum
- Heat treatment: T6 specification
- Ring type: Single ring
- Skirt coating: Permanent friction-reducing
- Design method: FEA-optimized
- Kit contents: Piston, rings, pin, clips
- Installation: Bolt-on replacement
- Origin: German engineering









