The 129ci and 132ci Big Bore Kits from S&S Cycle were made for 2017-up Harley-Davidson Milwaukee-Eight engines and offer big power, bringing stock engine displacement from 107ci up to 129ci or 114ci up to 132ci. The highlighted cylinder kit and non-highlighted cylinder kit are currently priced at $1,499.95 each. Read more in the press release below.

S&S Cycle 129- and 132-inch Big Bore Kits
Highlighted cylinders
S&S Cycle 129- and 132-inch Big Bore Kits
Non-highlighted cylinders

S&S Cycle specializes in the kind of power and thumping that makes your heart skip a beat. This obsession with power is proven by the latest efforts for the Milwaukee-Eight-powered Harley-Davidson models. The company’s bolt-in 129ci/132ci (that’s well over 2,000cc for you metric folks) Big Bore Kits are just this side of monstrous.

“The S&S R&D team has been working on this project for the better part of 18 months,” said David Zemla, S&S Cycle vice president of marketing, adding that the team had conducted “an intensive level of durability testing to develop the perfect combination of materials and piston shape.”

The stock engine increases from either a mild-mannered 107ci to a fire breathing 129ci or a 114ci to a 132ci model of tire-melting power.

Its latest is a 4.32-inch bore and it is slated for 11:1 compression ratio, so it’s happy with pump gas but will still complement a high lift cam. No case mods, no engine removal; just a massive set of jugs designed, tested, and manufactured here in the USA.

For more info and detailed specs, check out:


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