Wossner Piston Kit Yamaha YZ250 1988-1991 68.44mm 8134D050

A worn or damaged piston directly undermines your YZ250's power delivery, throttle response, and engine longevity. This Wossner kit restores—or significantly upgrades—your 2-stroke's performance with precision-engineered internals that handle sustained high-RPM abuse. Whether you're rebuilding after a failure or prepping for race season, a quality piston kit is non-negotiable for reliable power.

The Wossner 8134D050 delivers measurable advantages over OEM replacements. The proprietary skirt coating reduces friction and piston rock, translating to smoother operation, less noise, and improved ring seal. Built from 4032 T6 forged aluminum and validated through finite element analysis, this kit is engineered to withstand the demanding conditions 2-stroke racers impose on their engines.

This is a complete, bolt-on rebuild kit—no additional machine work required. Simply remove your top end, install the piston, rings, pin, and clips, and you're ready to ride.

• Fitment: Yamaha YZ250 (1988–1991)
• Bore diameter: 68.44mm
• Material: 4032 T6 forged aluminum
• Complete kit included: Yes
• Skirt coating: Permanent friction-reducing
• Heat treatment: T6 (high-load rated)
• Design method: Finite element analysis
• Origin: German engineering
• Installation: Bolt-on, top-end rebuild
• MPN: 8134D050