The Milwaukee-Eight™, which retains the classic 45-degree V-Twin architecture, will power all 2017 Touring and Trike models, in two displacements and three variations:
- Milwaukee-Eight™ 107 (107 cubic inches, 1,750cc) with precision oil-cooled cylinder heads for the Street Glide®, Street Glide® Special, Road Glide®, Road Glide® Special, Electric Glide® Ultra Classic®, Road King® and Freewheeler® models.
- Twin-Cooled™ Milwaukee-Eight™ 107 with liquid-cooled cylinder heads for the Ultra Limited, Ultra Limited Low, Road Glide® Ultra and Tri Glide® Ultra models.
- Twin-Cooled™ Milwaukee-Eight™ 114 (114 cubic inches, 1,870cc) with liquid-cooled cylinder heads for the CVO™ Limited and CVO™ Street Glide® models.
- Compared to the Twin-Cam 103 and 110, the Milwaukee-Eight™'s increased displacement, higher compression ratio and four-valve cylinder heads, which provide 50 percent more intake and exhaust flow capacity, result in 10 percent more torque across the board. Bikes equipped with the new engine are claimed to accelerate much faster off the line (8-11 percent quicker at 0-60 mph) and in top gear roll-ons (11-12 percent quicker at 60-80 mph).
Better air flow and combustion, including the use of dual spark plugs for each cylinder, are said to improve fuel economy. Precision oil or liquid cooling of the cylinder heads as well as repositioning the rear exhaust pipe and relocating the catalytic converter improves heat management, providing a more enjoyable riding experience for the rider and passenger.
As with the Twin-Cam engine, the Milwaukee-Eight™'s rocker arm-actuated valves never need adjustment as they are a hydraulic cam tensioner. But instead of the Twin-Cam's dual camshafts there's a single, chain-driven camshaft that's lighter, quieter, less complex and reduces friction. The rubber-mounted Milwaukee-Eight™ uses an internal counterbalancer to cancel 75 percent of primary vibration at idle, for a less eyeball-shaking experience at stops.
Harley® says the new engine's reduced mechanical noise allows the exhaust note to take on richer tone. Other improvements include a 50 percent increase in charging output for powering accessories, slimmer primary and air cleaner covers for more legroom, and-always important on Motor Company machines-enhanced curb appeal. And all bikes with the Milwaukee-Eight™ are equipped with a low-effort assist and slip clutch.