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Designed and manufactured in Germany by Wössner, this forged piston is aimed at demanding riders and mechanics in the Cross world. Machined from aluminum and treated on the skirt to reduce friction, it provides a robust base for the restoration or rebuilding of the listed 400 cm³ single-cylinder engines.
Delivered complete (ring(s), circlips, and pin), this piston is suitable for interventions on cross engines where the reliability of internal parts is crucial. Its finish and tolerances meet the assembly requirements for a B oversize bore.
Compatibility (examples): YAMAHA WR 400 F (CH04) 2000, YAMAHA YZ 400 F (CH03) 1999, YAMAHA YZ 400 F (CH01) 1998. Always check the bore size and engine reference before installation.