The mean mill is a new benchmark for factory-engineered American V-Twin performance.
Real Beefy
More than just a word, performance is a definite number at Harley-Davidson. Rolling out for early Spring 2023, that 'number' is the new Screamin' Eagle 135 cubic-inch Stage IV Performance Crate Engine. Real-world applications are yet to be tested, but the beefy motor is already being offered with “no compromises” and that guarantee is in writing!
Assembled Benchmark
Out of the box, the Motor Company is promising a hardcore mill—ready to run. Designed for late-model Touring bikes, the Milwaukee-Eight 135 is “engineered and tested as a complete collection of high-performance components and assembled from the bottom up at Harley-Davidson Powertrain Operations in Menomonee Falls, Wisconsin.” It is a new benchmark for factory-engineered American V-Twin performance.
Mean Coverage
The Milwaukee-Eight 135 offers the most displacement and power from a street-compliant engine ever built by Harley-Davidson. It is intended as a bolt-in option for the 2021 and later Touring chassis, with no special fabrication or engine-mount relocation required. When dealer-installed, the mean mill is backed by a two-year warranty through the Custom Coverage program.
Paired Power
Building on the hype, Harley-Davidson states that the street-tuned motor is “designed to run with a wide-open throttle at high engine speeds and provide instant passing power from cruising speed.” When installed, the motor must be paired with a Screamin' Eagle Pro Street Tuner to maximize performance. The result is a forty-nine-state emissions-compliant powerhouse.
Percent Version
The new Milwaukee-Eight 135 engine is pushing some serious numbers. Harley-Davidson states that it “delivers 143 lb-ft. of rear-wheel torque at 3500 RPM and 130 rear-wheel horsepower at 5500 RPM—approximately 28 percent more torque and 41 percent more horsepower at the rear wheel than a production Milwaukee-Eight 117 engine.” An 'Air/Oil-Cooled' version and a 'Twin-Cooled' version are available.
Direct Evidence
'Performance Baggers' is the latest and hottest trend in touring bikes. Harley-Davidson also credits the popularity of the MotoAmerica Mission King of the Baggers series and its own Screamin’ Eagle factory racing team. Evidence of this is the Milwaukee-Eight 135's 68mm throttle body and matching CNC-machined intake manifold—a direct takeoff from the race-prepped Road Glides.
Tuner Equation
There are a few caveats to the Milwaukee-Eight 135. The new motor does not fit the Trike lineup and, predictably, California model owners will be left out of the power equation. Installation does require the purchase of an exhaust, intake, various oil cooling components, and the previously mentioned Screamin' Eagle Pro Street Tuner for a required ECM recalibration.
Displacement Happiness
The Milwaukee-Eight 135 is also offered in chrome. Under the polished covers lurks a lumpy SE8-517 high-lift cam, with high-performance bearings and tappets, along with a billet cam plate and a billet oil pump. Enthusiasts with a 'no replacement for displacement' mindset are looking at a cool $7,999.95, before installation and additional parts. Looks like happiness can be bought after all!
>>Join in the conversation about the Screamin' Eagle 135 right here in Harley-Davidson Forums.
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