Cylinder Works 478cc Big Bore Kit - YZ450F / WR450F (03-06)
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- 30-day hassle-free returns
- Call us: 541-668-7503
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Boost displacement and power with the Cylinder Works Big Bore Cylinder Kit (P/N 23001-K02 / 0931-0426), designed as a complete bolt-on performance upgrade for your Yamaha YZ450F or WR450F.
✓ Fits:
- Yamaha YZ450F (2003-2005)
- Yamaha WR450F (2003-2006)
✓ Features:
- +3.00mm big bore (98.00mm total bore) for 478cc displacement
- 12.5:1 compression ratio - stronger midrange power
- Cylinder made in the USA, machined to OEM spec
- Nickel Silicon Carbide sleeve for reduced wear and superior heat dissipation
- Includes Vertex piston kit and gaskets for a complete top-end rebuild
- Bolt-on installation - no replating or case boring required
- Bore Size: 98.00mm (+3.00mm)Displacement: 478ccCompression Ratio: 12.5:1Engine Type: 4-StrokeWeight: 4.6 lb
✓ What's Included:
- Cylinder - Nickel Silicon Carbide plated, ready to install Vertex Piston Kit - piston, rings, wrist pin, and clips Top-End Gasket Kit - head, base, and exhaust gaskets included
- (No machine work required.)
Ships fast from DuneGoonShop!
📦 Shipping Information
In-stock items ship next business day. ModQuad parts dispatch Monday through Thursday.
Made-to-order and custom powder coat items show their lead time at the top of this page, right next to the truck icon. These are built fresh for you, so timing varies by brand and current backlog.
Need something by a specific date? Call us at 541-668-7503 before ordering and we will check stock and ETA on that exact part. We can often point you to an in-stock alternative from another distributor.
Questions? Contact us, we respond within 24 hours.
