Harley-Davidson flooded the market with Milwaukee-Eight upgrades in 2020. From the 131ci crate motor to Stage IV Screamin’ Eagle kits, the MoCo continued its build-a-block upgrade options and elevated capacities north of 2,000cc for the first time. Not to be left out of the power mod bonanza, longtime v-twin specialists S&S Cycle takes things to the next level with its new 590 cam. Paired with several other engine upgrades, the high-lift cam unlocks nearly 147 horsepower and 145 lb-ft of torque.

Compatible with 124ci and larger engines, the 590 cam increases air intake higher into the rpm range, resulting in more . That quality shifts peak power beyond the stock Milwaukee-Eight's redline. However, with more stress placed on the valvetrain, the new cam requires S&S Cycle’s heavy-duty springs and adjustable pushrods. The Wisconsin-based aftermarket brand also suggests precision tappets and cuffs along with the 590 install.

SS Cycle 590 Cam

To illustrate the potency of the big lift cam, S&S hopped up a Street Glide with its 131ci stroker kit, CNC-ported heads, larger throttle body, high-flow air cleaner, and the new 590. Compared to the stock 114ci Milwaukee-Eight, power increases by 80 percent and torque jumps by 30 percent thanks to the new cam.


Offered in chain and gear drive, S&S Cycle’s 590 camshaft kits retail for $193.95 and $387.95, respectively. All kits come complete with gaskets, bearings, and hardware necessary for installation, and to little surprise, the cam isn’t road-legal in California. With the King of the Baggers race fresh in everyone’s memory, we’re looking forward to more performance mods entering the v-twin market. Whether its Harley itself or the expansive aftermarket surrounding the brand, it looks like the Milwaukee-Eight's full potential is still being explored.

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