This Wiseco forged piston kit is designed for Yamaha YFM250RX (2008–2013) and XT250 (2013–2019) models. It features a 2.00mm oversize bore, bringing the actual bore to 76.00mm and increasing displacement to 263cc. Engineered for durability and performance, it includes a moly-coated skirt for reduced friction and improved wear resistance. The kit is suitable for high-performance applications, offering enhanced strength and fatigue resistance compared to cast pistons.

Features

• Forged piston construction for enhanced strength and durability


• Moly-coated piston skirt to reduce friction and improve wear resistance


• Direct OEM replacement


• Easy to install; professional installation recommended if unsure

Specifications

• Displacement: 263cc


• Bore (Standard): 74.00mm


• Bore (Actual): 76.00mm


• Oversize: 2.00mm


• Stroke: 58.00mm


• Compression Ratio (Actual): 9.5:1


• Skirt Coating: Moly

Cross-Reference OEM Part Numbers

• 40078M07600


• 2992XG (76.00mm Ring Set)


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


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

Vehicle Fitments

• YFM250RX (2008–2013)


• XT250 (2013–2019)