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S&S Cycle

S&S Cycle 2007+ BT 4.250in Bore 4.840in - Wrinkle Black w/o Highlight

$1,559.95

SKU: S0GE 910-0763

In Stock
In Stock
Ships by Aug 2
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

Part #: 910-0763

S&S has been building big bore kits since the 60s and has it down to an absolute science. Our latest efforts are aimed at the Milwaukee Eight (R) platform (2017 and newer big twins) and open up a whole new level of performance for these engines. Combining a new design forged piston with their 4.25" cylinders to net a tire melting 131 cubic inches when paired with their 4.625" stroker crank. We build our big bore kits and cranks to much tighter tolerarances and with higher quality materials than the factory parts. This new piston/cylinder kit will be a solid platform for massive power.

131" Kit, Wrinkle Black without Fin Highlights

MIA's Description

This kit increases Harley-Davidson Milwaukee-Eight (M8) engine displacement to 131 cubic inches. Designed for high-performance, it includes cylinders, pistons, rings, wrist pins, and circlips, featuring a wrinkle black finish. It works with the stock crankcase, retaining original engine serial numbers. For full 131" displacement, an S&S stroker flywheel is required. A 131" cam cover badge is included.

Fitment

Fitment Guaranteed

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandS&S Cycle
Part NumberS0GE 910-0763

Videos

S&S Cycle Big Bore Kit for Milwaukee-Eight Overview

S&S Cycle Big Bore Kit for Milwaukee-Eight Overview
BIG HORSEPOWER Kit Breakdown by Moonshine Horsepower | 131, 135, 139, & 143 MONSTER Horsepower

BIG HORSEPOWER Kit Breakdown by Moonshine Horsepower | 131, 135, 139, & 143 MONSTER Horsepower
S&S Big Bore Kits and Cylinder Heads for Harley Review at RevZilla.com

S&S Big Bore Kits and Cylinder Heads for Harley Review at RevZilla.com
Why you should get a 131 Kit on your Harley-Davidson

Why you should get a 131 Kit on your Harley-Davidson
How to Install a Big Bore Kit In a Milwaukee Eight Engine | Weekend Wrenching

How to Install a Big Bore Kit In a Milwaukee Eight Engine | Weekend Wrenching
Harley Davidson 107 M8 to S&S 136 Big Bore Stroker Kit

Harley Davidson 107 M8 to S&S 136 Big Bore Stroker Kit

Buy with Confidence

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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