Wiseco Crankshaft Kit WPC139 - Yamaha YZ450F 2003-2005

Product Description

Restore the power and reliability of your high-performance engine with the Wiseco WPC139 Crankshaft Kit designed specifically for the Yamaha YZ450F. Built to handle the rigorous demands of motocross and off-road riding, this complete bottom-end solution brings precision engineering and superior durability to your machine.

Each crankshaft assembly is factory assembled and precision trued to strict OEM specifications. Featuring double-forged connecting rods with improved grain flow, shot-peened surfaces to eliminate residual stress, and precision-engineered oiling slots, this kit maximizes rod strength, bearing life, and thermal resistance under extreme operating conditions.

Top Features: Wiseco Crankshaft Kit

• Factory-assembled and precision trued crankshaft engineered to OEM specifications.
• Double-forged Wiseco connecting rod with enhanced grain flow and shot-peened finish for superior stress resistance.
• Optimized radial running clearance and precision honing for an ultra-round, high-performance bearing surface.
• Precision-engineered oiling slots and double-drilled small ends maximize lubrication and cooling.
• Complete kit includes crankshaft assembly, main bearings, and bottom-end gasket kit.

Please review the detailed compatibility data below to ensure an exact fitment match for your dirt bike before finalizing your purchase.

Fitment List

Frequently Asked Questions

Q: What components are included in this crankshaft kit?
A: The kit includes the complete crankshaft assembly, main bearings, and a bottom-end gasket kit.

Q: Is the crankshaft ready for immediate installation?
A: Yes, it is factory assembled and precision trued to OEM specifications right out of the box.

Expert Pro-Tip: When installing a new bottom-end kit, always ensure the crankcase is meticulously cleaned and flushed of all metallic debris from any previous engine failure. Check crankcase main bearing alignment and use fresh assembly lube on all journal surfaces during installation to prevent dry starts.

Recommended Pairings:

• Yamaha YZ450F Performance Parts & Upgrades
• Yamaha 4-Stroke Dirt Bikes Performance Parts
• Engine Rebuild Kits Collection

At Moto-House MX, we carry the best brands in motocross and off-road performance. Our team has over 40 years of experience helping riders get more out of their machines. We pride ourselves on great customer service, and every item ships FAST - straight to your door.

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