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Athena P400485100029 144cc Big Bore Cylinder Kit with Cylinder Head (58mm Bore) - Premium 2-Stroke Performance Upgrade, Compatible with Yamaha YZ125 1997-2004

Description

UPGRADE YOUR DIRT BIKE TO THE NEXT LEVEL OF PERFORMANCE Extract massive power, aggressive low-end torque, and unmatched acceleration from your 125cc two-stroke racing engine with the Athena Big Bore Cylinder Kit (Part No. P400485100029), a premium race-proven package engineered in Italy to seamlessly convert your factory setup into a high-revving, high-output 144cc powerhouse. Entirely cast from high-grade aluminum and treated with a specialized Motor-Nicksil (Nickel-Silicon) coating, this cylinder guarantees exceptional thermal dissipation, minimal friction, and optimal wear resistance to deliver a substantial increase along the entire power curve while maintaining strict original-equipment reliability. This complete bolt-on kit comes loaded with everything required for a flawless installation—including a precision-machined 58mm big bore cylinder, a dedicated high-compression cylinder head, updated power valve components, a premium cast piston assembly, rings, wrist pin, clips, and a specific high-tightness multi-layer gasket set—allowing you to dramatically increase track performance without requiring any complex machining or structural engine modifications to your factory crankcase.

Athena P400485100029 144cc Big Bore Cylinder Kit with Cylinder Head (58mm Bore) - Premium 2-Stroke Performance Upgrade, Compatible with Yamaha YZ125 1997-2004

Product form

SKU: P400485100029

UPGRADE YOUR DIRT BIKE TO THE NEXT LEVEL OF PERFORMANCE Extract massive power, aggressive low-end torque, and unmatched acceleration from... Read more

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2 - 4 Business Days

$1,414.94

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    • Shipped today? Order within: Jul 09, 2026 14:00:00 -0500
    • Free shipping on all orders. (Shipping only available to lower 48 states)
    • Hassle Free, Returns within 30 days

    Description

    UPGRADE YOUR DIRT BIKE TO THE NEXT LEVEL OF PERFORMANCE Extract massive power, aggressive low-end torque, and unmatched acceleration from your 125cc two-stroke racing engine with the Athena Big Bore Cylinder Kit (Part No. P400485100029), a premium race-proven package engineered in Italy to seamlessly convert your factory setup into a high-revving, high-output 144cc powerhouse. Entirely cast from high-grade aluminum and treated with a specialized Motor-Nicksil (Nickel-Silicon) coating, this cylinder guarantees exceptional thermal dissipation, minimal friction, and optimal wear resistance to deliver a substantial increase along the entire power curve while maintaining strict original-equipment reliability. This complete bolt-on kit comes loaded with everything required for a flawless installation—including a precision-machined 58mm big bore cylinder, a dedicated high-compression cylinder head, updated power valve components, a premium cast piston assembly, rings, wrist pin, clips, and a specific high-tightness multi-layer gasket set—allowing you to dramatically increase track performance without requiring any complex machining or structural engine modifications to your factory crankcase.

    Returns & Delivery

    When will my order be delivered?

    We ship to all lower 48 US states Your order will be packaged and shipped the same day you ordered as long as you order before 2:00 pm CST.
    Delivery takes between 2-4 business days. You will receive an e-mail after ordering with your tracking number so you can track the packages progress to your address.

    Can I return my product?

    Orders can be returned or exchanged within 30 days of receiving the package, provided they are in original resalable condition. If the product has been used or damage, a restocking fee may occur. Please see our Return Policy for further clarification.

    How can I contact you if I have issues or questions?

    You may contact us at sales@massdepot.com Our dedicated customer support will answer your questions or concerns within 24 hours of you reaching out.

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