YFZ450R / YFZ450X Complete Engine Rebuild Kit – OEM Crankcases + Stock Bore

YFZ450R / YFZ450X Complete Engine Rebuild Kit – OEM Crankcases + Stock Bore

Regular price$2,813.00
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Fits All Yamaha YFZ450R & YFZ450X Models (2009–2019)
Everything you need to fully rebuild your YFZ450R or YFZ450X motor—featuring brand new OEM crankcases, a forged piston, and a complete matched rotating assembly. Built for racers and riders who want a fresh start with OEM-quality components.


What’s Included

  • Brand new OEM crankcases

  • New aftermarket stock bore cylinder

  • Wiseco forged piston + hi-temp rings

  • Chrome wrist pin & circlips

  • Hotrods or Wiseco crankshaft with connecting rod

  • Main, transmission, shift cam, and crank balancer bearings

  • Clutch arm & water pump bearings

  • Full top & bottom end gasket kit (MLS head gasket included)

  • Crankcase oil seal kit + valve stem seals

  • Water pump shaft, mechanical seal, and impeller

  • Brand new oil pump

  • K&N oil filter + NGK spark plug

  • Timing chain + complete clutch kit

  • DuneGoonShop stickers included

  • All parts are brand new – Runs on pump or race gas


🔧 Built for Performance

  • OEM-Quality Foundation: Start with new crankcases

  • Reliable Power: Forged internals and balanced rotating assembly

  • Complete Kit: No chasing down missing pieces

  • Peak Durability: Internals matched for maximum life


🧩 Fitment – Confirmed Compatibility

Fits ALL YFZ450R & YFZ450X Models:

  • YFZ450R (2009–2019)

  • YFZ450R SE (2009–2019)

  • YFZ450REL (2014 Team Yamaha Edition)

  • YFZ450RW (2012–2013 Custom Graphics)

  • YFZ450X / XSE (2010–2011 incl. Bill Balance Edition)


🛡️ Warranty & Return Policy

  • 1-Year Limited Warranty on qualifying components

  • Lifetime warranty on studs (failure during use only)

  • Cylinder (Alpha Cub): Replaced or repaired if it fails under normal use

  • All warranty claims require return of failed part for inspection

  • 30-Day Returns accepted on new, unused parts

  • Buyer’s remorse returns subject to 10% restocking fee + shipping deduction

  • Professional installation required for warranty coverage

We ship next day most of the time. Modquad parts are shipped Monday-Thursday. Engine Kits are 3-5 business days.

We don't do backorder! If your items has already sold you will be notified immediately and you money refunded on the spot.

Sold items are removed daily.

If you see it on this website, it is 100% in stock unless it just sold before you clicked buy.

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Customer Reviews

Based on 1 review
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Willie Harris
Yfz450

Well my mechanic said it was some good parts in the box. I'll let you know how the rebuild goes. Great I hope

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