Rumors abounded since earlier this year and today Harley-Davidson pulled the veil off of an all-new V-twin engine, the Milwaukee-Eight; it will power its touring bikes for 2017. The ninth in the lineage of the company’s Big Twin engines, the Milwaukee Eight is said to deliver more power and an improved motorcycling experience while retaining the iconic look, sound and feel of its predecessors. Bikernet is set to ride the 2017 touring line in a few days, so stay tuned for a full report on these pages.
Developed from a clean-sheet concept, the Milwaukee-Eight engine was designed to deliver quicker throttle response, more passing power, an improved sound and a smoother ride.
“The guiding principle behind the Milwaukee-Eight engine was our voice of customer research from every region of the world,” said Scott Miller, Harley-Davidson Vice-President of Styling and Product Development Strategy. “Riders asked us to create a new engine designed to enhance their motorcycle touring experience in every way. Those same voices also demanded that we stay true to our legacy and respect the defining elements of a Harley-Davidson V-Twin. It was a big challenge, but one we’ve met. With the Milwaukee-Eight, a new era of Harley-Davidson power, performance and innovation has been forged.”
Designed to power the 2017 Harley-Davidson Touring and Trikes, Milwaukee-Eight engines exist in two displacements and three variations:
Milwaukee-Eight 107 (107 CID, 1750cc) with oil-cooled cylinder heads for the Street Glide/Street Glide Special, Road Glide/Road Glide Special, Electra Glide Ultra Classic, Road King and Freewheeler models.
Twin-Cooled Milwaukee-Eight 107 (107 CID, 1750cc) featuring 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 CID,1870cc) featuring liquid-cooled cylinder heads for the CVO Limited and CVOTM Street Glide models.
Increased Performance
Harley says the Milwaukee-Eight engine produces 10 percent more torque than the engine it replaces in Touring models. The M-8 has a higher compression ratio and four-valve cylinder heads with 50 percent more intake and exhaust flow capacity. (think not only performance, but compliance with ever-stricter emission requirements). The valve train requires no adjustment as the design of the rocker arms enables valve lash to be set at the factory for life. Dual spark plugs for each cylinder contribute to more- efficient combustion (more to make the feds happy about emissions and keep The Company in business for years to come). A single chain-driven camshaft is lighter, mechanically less complex and creates less friction and noise. (That’s good news because it allows the exhaust note to be taken up a notch for your enjoyment).
Quicker Acceleration
Harley says the M-8 107 accelerates 11 percent quicker 0-60 mph, equal to a two to three bike length improvement, and 11 percent quicker from 60-80 mph in top gear, equal to a one to two bike length improvement, compared to the Twin Cam High Output 103.
The Milwaukee-Eight 114 accelerates 8 percent quicker 0-60 and 12 percent quicker 60- 80 than the Twin Cam 110TM. This should be loads of fun!
Heat Management
The Milwaukee-Eight engine offers improved rider and passenger thermal comfort due to reduced heat absorption, increased heat rejection and a redesigned exhaust system. Each Milwaukee-Eight engine features a precision cooling strategy based on the specific demands of the motorcycle model, using a targeted flow of either oil or liquid coolant around the hottest areas of the cylinder heads. A new knock sensor for each cylinder enables more-precise timing control. The rear exhaust pipe is re-positioned and the exhaust catalyst is relocated to move heat away from the passenger. Idle speed is lowered from 1,000 rpm to 850 rpm.
Improved Fit
A new, slimmer primary drive cover and the low-profile shape of the air cleaner cover provide improved rider legroom around the engine and an easier reach to the ground for many riders. All Milwaukee-Eight powered models are fitted with an Assist and Slip Clutch with improved hydraulic actuation that reduces clutch lever effort by 7 percent.
Reduced Vibration
The rubber-mounted Milwaukee-Eight engine features a single internal counter balancer that
cancels 75 percent of primary vibration at idle for a more-refined feel and more-comfortable experience for rider and passengers while retaining the classic character of Harley V-Twin engines.
Richer Exhaust Note
Lighter valves, a single camshaft, optimized cover designs and improved driveline components reduce mechanical powertrain noise. The engine intake and air cleaner are designed to reduce intake sound while ensuring maximum air flow. As a result, the new Milwaukee-Eight engine is mechanically quieter, enabling a richer exhaust tone, and meets all global noise and emissions standards while allowing the unmistakable rumble of its exhaust note to resonate.
Improved Charging
The Milwaukee-Eight engine charging system delivers 50 percent more output to the battery at idle to better support the power demands of Touring riders, including accessory lighting, performance audio, and heated gear and other accessories.
New Engine Styling
The Milwaukee-Eight engine features sleek, modern styling that respects the heritage of previous Harley-Davidson Big Twin engines.
“The Milwaukee-Eight engine is styled to project power,” said Brad Richards, Harley-Davidson Director of Styling. “I compare it to the back of a swimmer, lean in the waist but broad and muscular in the shoulders.”
“The rocker covers look like skin stretched taut over muscle, like the rocker arms are about to burst out of the engine,” said Richards. “For the first time since the Knucklehead, the rocker covers reflect the action going on below. And they are massive. When you sit on the bike you can look down and see more of this engine.”
To experience the 2017 Harley-Davidson Touring models for yourself, visit your dealer to schedule a test ride.