Wossner Complete forged A-rib Piston kitRef : 8104DA / 1093538001

WÖSSNER Forged Piston – Manufacturer Ref. 8104DA

Designed and machined in Germany by Wössner, this forged aluminium piston is aimed at demanding motocross riders. Its skirt features an anti-friction treatment to limit wear and promote consistent engine behaviour. The piston is supplied ready to install with the ring, circlips, and pin.

• Bore diameter: 47.50 mm
• Piston diameter: Ø 47.45 mm (tolerance A, oversize A)
• Material: forged aluminium
• Number of rings: 1
• Supplied with ring(s), circlips, and pin

Ideal for modifications and replacements on motocross engines, this forged piston offers the mechanical robustness expected on the track. Its design allows for good heat resistance and rotational stress handling, while maintaining precise guidance in the bore. Before installation, check the thickness of the ring, the condition of the cylinder, and the bore size to ensure correct piston clearance.

Compatibility examples: YAMAHA YZ 85 LW BIG WHEELS 19/16 (2026), YAMAHA YZ 85 (2026), YAMAHA YZ 85 (CB09) (2012). Always check the reference and bore size of your engine before ordering.