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Engines and Components› Pistons and Piston Rings

Athena

58mm Big Bore Kit 144cc

Name: 58mm Big Bore Kit 144cc
Brand: Athena
SKU: P400485100101

$802.19

SKU: P400485100101

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Overview

It features a 58 mm bore, resulting in 144 cc displacement. This kit is recognized for its performance, durability, and reliability, offering increased power without compromising engine reliability.

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This kit increases the engine's displacement to 144 cc with a 58 mm bore diameter. The intake and exhaust ports are optimized for gas flow, and cooling chambers are incorporated to prevent overheating during demanding use. Athena guarantees maximum durability and smoothness through a special nickel and silicon treatment of the barrel. The kit includes the aluminum cylinder, cylinder head, a complete piston with pin and rings, and all necessary gaskets. The modular cylinder head features an aluminum outer casing and a bronze inner dome, allowing for customization of compression and squish ratios while improving heat dissipation and extending engine life. Athena specifies that when the cylinder kit is disassembled, only specific Athena spare gasket kits should be used; OE replacement gaskets are not to be used. This product is designated for Race Use Only and is not intended for street use. All Athena products must be used in compliance with the specific national regulations of the member state where they are marketed or sold. Athena disclaims all responsibility for any improper use. The Athena Big Bore Cylinder Kit is compatible with the Yamaha YZ 125 models from 2022 to 2024. Installation requires boring of the engine crankcase.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

Brand	Athena
Part Number	P400485100101
Category	Engines and Components

Videos

What Is An Athena Big Bore Kit | YZ125 Build | What Comes In The Box

Athena YZ144 Kit - Big Bore Case Mods and Top End Install. Project YZ144 part 6

Yamaha YZ125 With 144cc Athena Big Bore Kit, GoPro

YAMAHA YZ 125 | ATHENA CYLINDER ASSEMBLY | RAW VIDEO

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