Discover how to upgrade your Kawasaki KX 250 with Athena's Extreme Big Bore Kit, which increases displacement to 300 cc, delivering a significant boost in power and torque across the entire power band. This kit is the ideal solution for riders who want to push their bike's performance beyond standard limits while maintaining the legendary handling and lightness of this motocross machine.
Enhance Your Kawasaki KX 250 Performance
The kit includes an aluminum alloy cylinder with an 85 mm steel bore, a high-quality forged piston complete with pin and rings, and all necessary gaskets. This cylinder kit results from years of off-road and racing research and development, ensuring smooth and continuous power delivery suitable for all RPM ranges.
Electronic Innovation with GET Boost
Included in the kit is the GET Boost electronic module, developed by Athena’s GET division, which takes your Kawasaki KX 250’s performance to the next level. GET is globally recognized for its collaborations with top off-road teams, including MXGP and AMA Supercross. With GET Boost, you can fully leverage the Big Bore kit’s performance without needing to modify the original ECU or electrical system.
Easy Installation and Maximum Integration
Installing the GET Boost is straightforward: simply disconnect the connectors from the primary injector and throttle body, and connect them to the GET auxiliary harness. The GET Boost module, pre-calibrated specifically for this cylinder kit, connects quickly and allows you to get the most out of your engine safely and reliably.
Cylinder Technical Specifications
The cylinder is made from a high-silicon aluminum alloy with an integrated steel bore through Athena’s exclusive co-fusion process. This process ensures a perfect bond between the aluminum and steel, improving heat transfer and preventing premature wear. The bore geometry is designed to ensure a perfect combustion seal, preventing pressure loss and fluid or gas leaks.
High-Performance Forged Piston
The forged piston, crafted from aluminum alloy, combines strength and lightness. CNC machining ensures tight tolerances and precise geometries, with a molybdenum disulfide coating that reduces friction and noise. The aerospace-grade steel pin, coated with DLC, guarantees hardness and low friction for unparalleled durability and reliability.
High-Quality Gaskets
The included gasket set is designed to provide optimal sealing with the new cylinder. The head gasket is an MLS (Multi-layer Steel) type, made from stainless steel and laser-cut with the latest technology, ensuring perfect and long-lasting adherence under all conditions.
Take Your Kawasaki KX 250 to the Next Level
The Big Bore Kit for Kawasaki KX 250 with GET Boost is the ultimate choice for riders who want to maximize their bike’s performance. Increased power, superior reliability, and a riding experience that will make you enjoy every moment on the track or off-road. Get ready to never want to get off your bike again!
Confirm the exact year, make, model and trim before ordering. Send us SKU 227186 with your vehicle info and we can help verify fitment.
Shipping services and final delivery cost are shown at checkout. Returns are confirmed before an RMA is issued — parts generally need to be uninstalled, unused and in original packaging. Full policy.
