A forged aluminium piston kit designed as a standard-compression replacement for the 95.00 mm standard bore, with a size grade C piston to match Yamaha’s A/B/C cylinder grading. The piston features a hard-anodised crown and MOS2-coated skirt, and is supplied complete with piston rings, wrist pin and circlips for reliable service.

Features

• Forged aluminium construction for strength and durability


• Hard-anodised crown to resist heat and carbon build-up


• MOS2 (moly) skirt coating to reduce friction during running-in


• CNC-machined dome for consistent volume and finish


• Supplied with piston rings, wrist pin and circlips


• Size grade C to match Yamaha cylinder grading

Specifications

• Manufacturer part number: FX-40045-C


• Bore size (nominal): 95.00 mm (standard)


• Piston diameter (grade C): 94.97 mm


• Compression ratio: 12.5:1 (standard)


• Application: Single-cylinder, four-stroke


• Components included: Piston, ring set, wrist pin, two circlips

Cross-Reference OEM Part Numbers

• 5TJ-11631-00


• 5TA-11631-00


• 2S2-11631-20

Vehicle Fitments

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  Yamaha YZ450F 2003–2009