The Wiseco forged piston kit with a 74.00mm bore is designed as a direct replacement for Yamaha YFM250R Raptor (2008–2013), YFM250RX (2008–2013), and XT250 (2013–2019) models. Built in the USA, this high-performance piston is forged for strength and durability, with a moly skirt coating to reduce friction and wear.

Features

• Forged piston designed for high strength and resistance to impact and fatigue


• Moly skirt coating for reduced friction and improved wear resistance


• Manufactured in-house with full control over the forging and machining process


• Direct OEM replacement


• Made in the USA

Specifications

• Displacement: 249 cc


• Bore (Standard): 74.00 mm


• Actual Bore Diameter: 73.95 mm


• Stroke: 58.00 mm


• Compression Ratio (Actual): 9.5:1


• Skirt Coating: Moly


• Bore Oversize: STD

Cross-Reference OEM Part Numbers

• Piston: 4951M07400


• Part No.: 56-W4951.WI


• Ring Set: 2913XA


• Locks: CW17 (17mm Round Wire Locks - Set of Two)


• Pin: S688 (17 x 42 mm Non-Chromed TW)

Vehicle Fitments

• Yamaha YFM250R Raptor 2008–2013


• Yamaha YFM250RX 2008–2013


• Yamaha XT250 2013–2019