BRC YAMAHA 500cc CONVERSION KIT 1999-2025, BOLT IN 500CC CONVERSION
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Yamaha 500cc conversion kit. This is a bolt-in 500cc counterbalanced 2-stroke conversion based on the YZ250 platform. Requires components from a donor Yamaha YZ250 engine from 1999-2025. Delivers strong motocross-focused performance with smooth, linear power delivery. Features a pneumatic power valve system and a triple blade power valve for improved bottom-end performance. Accepts donor Yamaha YZ250 and YZ250X transmission components. Remains kick-start compatible with a decompression button fitted to aid starting. Includes a dedicated exhaust pipe and silencer. Fits 2005-2025 aluminium frames without fabrication. 1999-2004 steel frames require minor modification. Designed to use the stock carburettor. Engine capacity is 499cc, producing 60+ hp and 50+ ft-lb torque. Features an integral counterbalance shaft to reduce vibration.
- SKU
- BRC-YZM500_99-21
- Brand
- No Brand
- Availability
- In Stock (2)
- SKU
- BRC-YZM500_99-21
- Brand
- No Brand
- Availability
- In Stock (2)
FULL DESCRIPTION
BRC 500cc Two-Stroke Conversion Kit for Yamaha YZ250 Platform
Transform your Yamaha YZ250 into a powerful 500cc machine with this bolt-in conversion kit. Designed for motocross enthusiasts, this kit delivers strong performance with smooth, linear power delivery, enhancing your riding experience. It utilizes a counterbalanced two-stroke design based on the YZ250 platform, requiring components from a donor Yamaha YZ250 engine.
Key Features:
- Bolt-in 500cc counterbalanced two-stroke conversion.
- Requires donor Yamaha YZ250 engine components.
- Engineered for potent motocross-focused power delivery.
- Features a pneumatic power valve system for smooth, linear power.
- Includes a triple blade power valve for improved bottom-end performance.
- Compatible with donor Yamaha YZ250 and YZ250X transmission components.
- Retains kick-start functionality.
- Equipped with a decompression button for easier starting.
- Comes with a dedicated exhaust pipe and silencer designed for optimal fit and performance.
- Integral counterbalance shaft significantly reduces vibration for a smoother ride.
- Designed to integrate seamlessly with the stock carburettor for optimal fuel delivery.
Performance Specifications:
- Engine Capacity: 499cc
- Horsepower: 60+ hp
- Torque: 50+ ft-lb
Installation Notes:
This kit is designed for direct bolt-in installation on 2005-2025 aluminium frame models without the need for fabrication. For 1999-2004 steel frame models, minor modification will be required.
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UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. Delivery details
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