Yamaha WR 250 F (RE 25) [2018] - forged pistons

PROX forged pistons for the Yamaha WR 250 F

The PROX forged piston is designed for the Yamaha WR 250 F (RE 25) built in 2018. As a forged aluminum version, it combines the specified piston geometry with a special aluminum alloy that reduces friction and supports reliability.

Piston for the 4-stroke engine

The version has a flat crown with a raised top and 4 valve pockets. This shape represents the specified specification for the 4T engine. The piston compression is standard and specified as 13.5/1.

Technical data

• Brand: PROX
• Piston type: forged
• Material: aluminum
• Diameter Ø: 76.95 mm
• Letter oversize: A
• Oversize: STD
• Piston compression: Standard, 13.5/1
• Rings Quantity: Set
• Stroke: 4T
• Specificity: flat crown with raised top / 4 valve pockets

Vehicle assignment

The forged piston is assigned to the Yamaha WR 250 F (RE 25), built in 2018. Before making a selection, the vehicle model, year of manufacture and the dimensions listed should be compared with the existing engine.

Selection note

The diameter of 76.95 mm, the oversize letter A and the STD marking are particularly relevant for the assignment. The information about the flat crown, the raised top part and the 4 valve pockets support the check of the appropriate piston design.