Milwaukee Eight Engine | Teddy Morse's Daytona Harley-Davidson® (2024)

For 2017, Harley-Davidson® is launching the ninth generation of its venerable Big Twin, called the Milwaukee-Eight. It is named in honor of its birthplace and its number of valves-twice as many as found on the Twin Cam motor that's been in the lineup since 1999. Harley-Davidson® says the new engine platform provides faster throttle response, more torque, better sound, improved fuel economy and a smoother ride.

Other changes for 2017 include all-new front and rear suspension for Touring models, available ABS and Smart Security System for the Street 500/750 models, updated CVO® models (Limited, Street Glide and Pro Street Breakout) and a full selection of street-legal Screamin' Eagle Performance components for the Milwaukee-Eight, including Stage I, II and III kits that deliver up to 24 percent more torque.

Cutaway of the Milwaukee-Eight 107, which Harley-Davidson® says offers faster throttle response, more torque, better sound, improved fuel economy and a smoother ride than the Twin Cam 103.

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 Glid®e, Road Glide Special®, Electric Glide Ultra Classi®c, 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.

Below are the specifications for the new engines:

• ENGINE 114:

  • Engine Twin-Cooled&tm; Milwaukee-Eight&tm; 114
  • Bore 4 in.
  • Stroke 4.5 in.
  • Displacement 114 cu in
  • Compression Ratio 10.5:1
  • Fuel System Electronic Sequential Port Fuel Injection (ESPFI)

• PERFORMANCE

  • Engine Torque Testing Method J1349
  • Engine Torque 124 ft-lb
  • Engine Torque (rpm) 3,250
  • Lean Angle, Right (deg.) 34.3
  • Lean Angle, Left (deg.) 33.4
  • Fuel Economy: Combined City/Hwy 43 mpg

Their iconic look, distinctive sound and massive torque make them instantly recognizable, but the Milwaukee-Eight® 107 and Milwaukee-Eight® 114 engines take the Harley-Davidson® V-Twin to a place it's never been. They're the most powerful, coolest-running motors we've ever built. Smoother, stronger and more durable. With crisper throttle response and truer, cleaner sound. Four valves per cylinder, single chain-driven cam, dual spark plugs, counter-balanced and rubber mounted. Developed and proven over countless miles and millions of hours. Every single part is new, engineered to give you more performance and more of the feeling you want from an engine. Today, it's a whole new ride.