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S&S Cycle

S&S Cycle 2017+ M8 Models 4.250in Bore x 4.5in Stroke 114 To 128 Big Bore Kit

$1,643.95 $1,457.06 Save $186.89

SKU: S0GE 910-0684

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In Stock
Ships by Jun 15
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30 Days Return
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Description

The S&S 910-0684 Big Bore Kit converts 114/117 M8 Harley-Davidson models to 128 cubic inches. This bolt-on kit features a wrinkle black finish with highlighted fins and includes premium aluminum cylinders with cast-in iron liners, forged pistons, rings, and gaskets. It has a 4.250″ bore, 4.5″ stroke, and an 11:1 compression ratio, compatible with stock cylinder heads.

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Specifications

BrandS&S Cycle
Part NumberS0GE 910-0684

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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