Yamaha 5UP-11400-10-00 Crankshaft Assembly

Technical specifications for Yamaha OEM crankshaft assembly part number 5UP-11400-10-00. This component serves as the primary rotating assembly converting reciprocating piston motion into rotational torque within the 250cc two-stroke liquid-cooled engine platform. The assembly includes forged steel crankshaft webs, connecting rod big-end bearing, and main journal bearings pre-installed. Manufactured to OEM tolerances for direct replacement without machining. Compatible with Yamaha YZ250 model years 2003 through 2023 and YZ250X model years 2016 through 2023. Material composition features high-strength forged steel construction with case-hardened bearing surfaces. Dynamic balancing performed to OEM specifications for vibration reduction at high RPM operation. Press-fit connecting rod assembly with needle roller bearing arrangement.