Rareelectrical OEM Grade Piston Pin Compatible with 2001-2015 Gas Gas Ec-F Yamaha Wr-F Yz-F 250Cc 4-Stroke 16Mm Wrist Pin 5Nl-11633-00-00 Top End Rebuild Outer Case-Hardened Mirror-Polished 249Cc

Piston Pin (Wrist Pin) — 16mm — Gas Gas EC-F 250 / Yamaha WR-F 250 / YZ-F 250 Specifications: Outer Diameter: 16mm Material: Case-hardened chrome steel — heat treated for maximum durability Surface Finish: Mirror-polished to minimize friction and wear Fitment: Direct OEM replacement — drop-in fit with no modifications Engine Compatibility: 249cc DOHC 4-Valve 4-Stroke Single Cylinder — Liquid Cooled Bore × Stroke: 77mm × 53.6mm Gas Gas EC-F 250 (2010-2015) — Yamaha-sourced engine Yamaha WR-F 250 (2001-2013) — Enduro Yamaha YZ-F 250 (2001-2011) — Motocross Function: The piston pin (also called a wrist pin or gudgeon pin) is the hardened steel shaft that connects the piston to the connecting rod small end. It transfers combustion force from the piston to the connecting rod while allowing the rod to pivot as the crankshaft rotates. A worn, scored, or loose piston pin causes knocking noise, accelerated bore wear, and potential catastrophic engine failure. When to Replace: During any top-end rebuild (piston, rings, cylinder re-bore/re-plate) When pin shows visible wear, scoring, discoloration, or blue heat marks When pin has measurable play in the connecting rod small end bearing Recommended every 2nd piston replacement even if pin appears serviceable Installation Notes: Always replace piston pin circlips — never reuse old circlips Apply assembly oil or two-stroke premix to pin before installation Ensure circlips are fully seated in their grooves — improper seating causes engine damage Verify connecting rod small end bearing condition before reassembly ADDITIONAL CROSS-REFERENCES: Compression Ratio: 12.4:1 (YZ-F), 11.8:1 (WR-F)

• Compatible with Gas Gas, Yamaha. Please verify your OEM part number from your original unit to help ensure fitment.
• Replaces: Manufacturer Part Number: / 04.1644.4 / Cross-Reference Oem Part Numbers: / Yamaha: 5Nl-11633-00-00 / Pin Specifications: / Outer Diameter: 16Mm / Material: Case-Hardened Chrome Steel / Surface Finish: Mirror-Polished For Minimal Friction / Engine Specifications: / 249Cc Dohc 4-Valve 4-Stroke Single Cylinder — Liquid Cooled / Bore × Stroke: 77Mm × 53.6Mm / Compression Ratio: 12.4:1 (Yz-F), 11.8:1 (Wr-F) / Notes: / Piston Pin (Wrist Pin) Connects
• Applications: Gas Gas Models: / Ec-F 250Cc 4-Stroke — 2010-2015 / Yamaha Models: / Wr-F 250Cc 4-Stroke — 2001-2013 / Yz-F 250Cc 4-Stroke — 2001-2011
• Applications: ...
• Piston Pin Source: Aftermarket