Rareelectrical Piston Pin Compatible with 1999-2025 Yamaha Yz 250 Yz-X 250 18Mm 2-Stroke Wrist Pin 5Cu-11633-00-00 Top End Rebuild Suzuki Rm Fits All Yz 249Cc 5Cu-11633-10-00 5Up-11633-00-00 New

Piston Pin (Wrist Pin) — 18mm — Suzuki RM 250 / Yamaha YZ 250 Specifications: Outer Diameter: 18mm 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: Suzuki RM 250 (2003-2012): 249cc 2-Stroke — Liquid Cooled — 66.4mm × 72mm Yamaha YZ 250 (1999-2025): 249cc 2-Stroke — Liquid Cooled — 66.4mm × 72mm Yamaha YZ-X 250 (2016-2025): Cross-country variant — same engine 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 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 Competition 2-stroke engines see extreme loads — inspect pin for wear at every rebuild Fits all YZ 250 special editions: 50th Anniversary, Monster Energy, YZ-X

• Compatible with Suzuki, Yamaha. Please verify your OEM part number from your original unit to help ensure fitment.
• Replaces: Manufacturer Part Number: / 04.1853.3 / Cross-Reference Oem Part Numbers: / Suzuki: 12151-37F00 / Yamaha: 5Cu-11633-00-00 / Yamaha: 5Cu-11633-10-00 / Yamaha: 5Up-11633-00-00 / Pin Specifications: / Outer Diameter: 18Mm / Material: Case-Hardened Chrome Steel / Engine Specifications: / 249Cc 2-Stroke Single Cylinder — Liquid Cooled — Power Valve / Bore × Stroke: 66.4Mm × 72Mm / Notes: / Piston Pin (Wrist Pin) Connects Piston To Connecting Rod Small
• Applications: Suzuki Models: / Rm 250Cc 2-Stroke — 2003-2012 / Yamaha Models: / Yz 250Cc 2-Stroke — 1999-2025 / Yz 50Th Anniversary 250Cc 2-Stroke — 2024 / Yz Monster Energy 250Cc 2-Stroke — 2022-2025 / Yz-X 250Cc 2-Stroke — 2016-2025
• Applications: ...
• Piston Pin Source: Aftermarket