What does 'top end' refer to in an engine?

The 'top end' of an engine typically includes the cylinder heads, valves, pistons, and the upper part of the cylinders. This gasket kit is designed to replace the seals and gaskets in these specific areas.

What is the significance of the .040 head gasket?

The .040 inch thickness of the head gasket is a specific measurement important for maintaining the correct compression ratio. Using the correct thickness ensures the engine performs as intended after a top-end rebuild or modification.

Does this kit include everything needed for a top-end gasket replacement?

Yes, this kit is designed to include all the necessary gaskets for a complete top-end repair or replacement on compatible M8 engines. It replaces the OEM part number 25700729.

Twin Power 17-Up M8 Top End Gasket Kit Replaces H-D 25700729 M8 3.937 Bore 107 CID .040 Head Gasket

Specifications

Brand: TwinPower
Part #: 043360
UPC: 887337403151

Twin Power 17-Up M8 Top End Gasket Kit Replaces H-D 25700729 M8 3.937 Bore 107 CID .040 Head Gasket

Name: Twin Power 17-Up M8 Top End Gasket Kit Replaces H-D 25700729 M8 3.937 Bore 107 CID .040 Head Gasket
Brand: TwinPower
SKU: twinpower-twin-power-17-up-m8-top-end-gasket-kit-replaces-h-d-25700729-m8-3-937--t14-702708
Price: 279.54 USD
Availability: BackOrder

$279.54

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Twin Power M8 Top End Gasket Kit for 17-Up M8 engines. Includes .040 head gasket for 107 CID. Made in USA.

Key Features

Fits 2017-2021 Harley-Davidson M8 models.
Includes all gaskets needed for top-end repair or replacement.
Features a .040 inch head gasket for 3.937 inch bore, 107 CID engines.
Replaces Harley-Davidson part number 25700729.
Made in the USA.

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Will this fit your vehicle?

Product Details

Twin Power is known for making well-built parts for Harley-Davidson motorcycles. If you're rebuilding the top end of your M8 engine, this gasket kit is what you'll need. It replaces Harley-Davidson part number 25700729 and is specifically designed for the 3.937-inch bore, 107 cubic inch M8 motor, featuring a .040 inch head gasket.

This kit includes all the gaskets required for a top-end repair or replacement. Having all the necessary gaskets in one package saves you time and ensures you have the correct parts for the job. The head gasket is precisely .040 inches thick, which is important for maintaining the correct compression ratio after a rebuild or modification. These gaskets are made in the USA, reflecting a commitment to solid manufacturing.

This kit fits a wide range of Harley-Davidson models from 2017 through 2021, including popular bikes like the Road King, Street Glide, and Heritage Classic. Make sure to check the full fitment list to confirm it's right for your specific motorcycle.