Cylinder Works 66.4mm Cylinder Kit - 99-25 Yamaha YZ250
- Ships next business day
- 30-day hassle-free returns
- Call us: 541-668-7503
- Secure checkout — Pay in 4 available
✓ Fits
- 1999 to 2025 Yamaha YZ250 (2-stroke)
- Standard bore replacement - direct fit, no machine work needed
✓ Features
- Complete standard bore top end kit - cylinder, Vertex piston kit, and gaskets in one package
- Nickel silicon carbide plated cylinder for excellent wear resistance and a longer service life
- Matched to Vertex pistons for proven longevity, consistent performance, and quieter operation
- Looks just like the stock cylinder - a clean OEM-style replacement
- Replacement pistons, rings, and gasket sets available separately to extend the life of the kit
✓ What's Included
- 66.40mm standard bore Cylinder Works cylinder
- Vertex piston kit with rings, wrist pin, and circlips
- Top end gasket set
✓ Specs
- Bore: 66.40mm (standard)
- Cylinder plating: nickel silicon carbide
- Engine type: 2-stroke
- Weight: approximately 10 lb (4.5 kg)
- Manufacturer: Cylinder Works (brand #20009-K02)
- WPS part number: 422-20009K2
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.
