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SHIPPING UPDATE: Due to high demand, orders are currently processing in 5-7 business days. Need it faster? Contact us to upgrade to expedited shipping! If you’ve found the item elsewhere or can’t wait, no problem—we completely understand. Just reach out to us, and we’ll cancel your order. Thanks for your patience and support! BRAPPPPPPPPPP!

23-24 KX250 KX 250X 300cc 85mm Athena Extreme Big Bore Kit Cylinder Piston & CDI

by Athena
Save 10% Save 10%
Original price $999.95
Original price $999.95 - Original price $999.95
Original price $999.95
Current price $898.88
$898.88 - $898.88
Current price $898.88

P400250100030,S5F08500006B,P400250160030,S5F08500006A,11005-0717, 13001-0820,P400250100018,11004-0079,11004-073811004-0079,11004-0738,11005-0586,11061-0357,120CA0625,13001-0714,13001-0730,13008-0028,13002-0030

Unlock Power with the Athena 85mm 300cc Big Bore Top End Cylinder Piston Rebuild Kit for 2023-2024 Kawasaki KX 250 / KX 250X

Revitalize your ride with the Athena 85mm 300cc Big Bore Top End Cylinder Piston Rebuild Kit, designed specifically for the 2023-2024 Kawasaki KX250F. Elevate your motorcycle's performance like never before with this top-of-the-line big bore kit, engineered for reliability and maximum power.

Fits Kawasaki KX250 2023-2024 / KX250X 2023-2024

Athena Part# P400250100030

85mm bore: the maximum increase ever

No crankcase machining needed

Racing Forged Piston with fully open boxed bridged design and anti-friction coating

Aluminum alloy Cylinder with Steel Cylinder Liner

Why Choose Athena?

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!

Optimize your Kawasaki KX 250's performance with Athena’s Extreme Big Bore Kit and discover a new world of power and excitement.

Experience Peace of Mind: All Athena products come with a warranty, so you can ride confidently knowing you have a reliable, high-performance upgrade.

Transform your Kawasaki KX250F into a powerhouse with the Athena 85mm 300cc Big Bore Top End Kit. Whether you're hitting the trails or racing on the track, this kit is your ticket to an exhilarating ride. Order now and unleash the full potential of your bike!

MADE IN ITALY

BPRATV - The Best Parts. The Best Performance. The Best Price.
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