When Indian launched the opening salvos in a V-twin cruiser motorcycle power war with its new 122-horsepower and 128 lb-ft PowerPlus engine, a 108 cubic inch engine found in the new Indian Challenger, Harley-Davidson was perhaps caught with its pants down. The Motor Company’s previous best engine just wasn’t good enough to beat the PowerPlus anymore. Time to introduce a new crate engine with an even bigger displacement and torque number to keep customers coming back to the Bar and Shield. Enter the new Screamin’ Eagle 131.
Available in oil-cooled ($US6,195 ($9,235)) and twin-cooled ($US6,395 ($9,533)), the new engine is available as an upgrade for your existing 2017 and up HD Touring chassis originally equipped with the Milwaukee Eight V-twin. Instead of a measly 119 lb-ft of torque and 100.5 horses of the highest spec Milwaukee Eight, the Screamin’ Eagle pumps out 131 lb-ft and 121 hp. A bolt-in 20 per cent power increase is nothing to sneeze at. But as with everything Harley, it doesn’t come cheap.
The Screamin’ Eagle achieves this power boost by slamming some 4.31-inch bore 10.7:1 compression pistons and cylinders on the Milwaukee Eight’s 4.5-inch stroke crankshaft. The same four-valve pushrod cylinder heads are given an extra 1mm of diameter per valve to increase airflow in and out. Then a high-lift camshaft, higher flow fuel injectors, and a larger throttle body are fitted.
If the engine is installed by a Harley service station the engine even comes with a 24 month warranty.
If I were flush with Harley-Davidson buying cash, it might not be the worst idea to go grab a three-year-old Harley with the least powerful 107-inch Milwaukee Eight engine and swap this bad boy in for a fresh warranty, a fresh engine, and a bunch more power. This engine would slap in a used Road King.