PISTON KIT 02-07 KTM EXC450 89, WOSSNER WOSSNER 8581DA 59430007000

Wossner forged piston kit with an 89mm bore, designed for KTM EXC 450 Racing, Beta RR450, and Polaris Outlaw 450 MXR models. Engineered for optimal combustion chamber heat transfer and uniform bearing surface under heat expansion, reducing localized pressure and piston collapse. Manufactured in Germany for durability and precision.

Features

• Forged piston for superior strength and design
• Optimized heat transfer to cylinder walls
• Elliptical design for uniform bearing surface and even thrust load distribution
• Manufactured in Germany

Specifications

• Bore: 89mm
• Standard size piston (PN# 8581DA)
• Lock Part Number: CW20
• Pin Part Number: WP038
• Ring Set Part Number: 890XSY
• Displacement: 449 cm³
• Stroke: 72.00mm
• Clearance: 0.04mm
• Wossner Compression Ratio: OEM
• OEM Compression Ratio: 11.10:1
• Dome Volume: +7.10 cm³
• Compression Height: 23.50mm

Cross-Reference OEM Part Numbers

• 59430007000
• 4941M08900

Vehicle Fitments

• KTM EXC 450 Racing (2003-2007)
• Beta RR450 (2005-2009)
• Polaris Outlaw 450 MXR (2008-2011)

Dispatch Times

Local Stock: Dispatches in < 24 hours

Parts showing as available at our Warehouse in Gorey ship the same business day if ordered before 1pm. 

Supplier Stock: Dispatches in 2-4 Days

Parts showing as available at our Supplier Warehouse are ordered from our supplier and delivered to us before we can dispatch. More info is available on this page under "Stock Availability".

OEM Special Order: Dispatches in 3-10 Days

This website does not have access to live stock levels from our OEM Suppliers. In most cases the parts will be available but in the case of backordered parts we will notify you. We receive parts from Yamaha in 3-4 days, All others including Honda, Suzuki, Kawasaki, Polaris please allow 7-10 days for us to receive the parts. 

Delivery Times

Ireland & Northern Ireland:

1-2 Days using GLS/An Post

Germany, France, Netherlands, Belgium:

3-5 Days using GLS/Fedex

Italy, Spain & Other EU Countries:

4-7 Days using GLS/Fedex