Flight of the Screamin' Eagle

ROAD TEST: 2017 Harley-Davidson Street Glide Special Review

2017 Laguna Orange Street Glide Special 107ci with Screamin’ Eagle Performance upgrades

By Koz Mraz
Screamin’ Eagle was originally a line in the HD catalog offering hard-parts, chrome dash, chain guards etc.  In 1999 Harley-Davidson offered a deluxe version of the FXDWG Wide Glide to the public.  Their first factory custom was specially outfitted with factory installed Screamin’ Eagle parts and accessories, custom paint and seats.  About 200 bikes rolled off the line that year and the Motor Company realized they were onto something. In 2009, Harley-Davidson dropped the “Screamin’ Eagle” name from its Custom Vehicle Operations division and began to refer to them as simply “CVO.”  This family of motorcycles models are created using special features for the CVO line still include branded Harley-Davidson parts from their accessories catalog, hand-painted pinstripes, custom seats, trunks, paint, and electronic accessories.  The Screamin’ Eagle name now primarily refers to performance upgrades offered by Harley-Davidson.

The current 2017 parts catalog contains 73 pages of Stage I, II, III and IV Screamin Eagle’ performance upgrade kits for its latest engine platform, the Milwaukee-Eight. In stock form, the 107 produces around 93 horsepower, and the 114 around 101 horsepower. “Screamin’ Eagle Performance Products are not an after-thought or an add-on for Milwaukee-Eight. These kits were engineered alongside the engine for factory-level quality and fit, which is why only Harley-Davidson dealers can offer 50-state, U.S. EPA compliant Screamin’ Eagle performance parts backed by a factory warranty.

“We’ve designed this amazing Screamin’ Eagle Stage IV kit for the performance fanatic,” said Harley-Davidson Senior Product Manager Scott Miller. “Big-bore cylinders, a monster throttle body, ported heads, and a high-lift cam combine to deliver stump-pulling torque throughout the rpm range and up to 52 percent more power than the stock Milwaukee-Eight engine.
“The Screamin’ Eagle Milwaukee-Eight Stage IV Kit is a system-matched collection of components created by the same Harley-Davidson engineering team that designed and developed the Milwaukee-Eight engine,” said Miller. “Upgrading the engine with genuine H-D parts supports a performance gain without sacrificing warranty, drivability or reliability. There are no compromises.”
Screamin’ Eagle Milwaukee-Eight ported cylinder heads are a key component of the Screamin’ Eagle Milwaukee-Eight Stage IV Kit. Based on a unique Screamin’ Eagle casting, these cylinder heads optimize air/fuel flow when paired with a Screamin’ Eagle 64mm throttle body.

The ports are meticulously machined on a five-axis CNC machine to increase the volume and velocity of the intake charge for improved efficiency of cylinder filling and to maximize the effect of exhaust scavenging. The Screamin’ Eagle ported heads are equipped with high-performance valve springs that remain stable with high-lift cams in high-RPM operation.
The SE8-515 camshaft, designed in conjunction with the Screamin’ Eagle Milwaukee-Eight Stage IV Kit, offers a high-lift and long-duration profile to efficiently fill the combustion chamber and retain 50-state street-legal emissions compliance.
Screamin’ Eagle 4.075-inch bore bolt-on cylinders and matching pistons increase displacement of Milwaukee-Eight 107 engines to 114 cubic inches, and take Milwaukee-Eight 114 engines to 117 cubic inches. The Screamin’ Eagle Milwaukee-Eight Stage IV Kit can be installed without removing the engine from the chassis.

Harley-Davidson Screamin’ Eagle Milwaukee-Eight Stage IV Kit Includes:
• CNC Ported Cylinder Heads with Performance Valve Springs
• 64mm Throttle Body
• High Flow Injectors (5.5g/s)
• 4.075-inch Bolt-On Cylinders
• Forged 11:1 High Compression Aluminum Coated Pistons
• High Performance Piston Rings
• SE8-515 Cam
• Cam Bearing Upgrade
• High Performance Tappets
• Multi-layer Coated Head Gaskets
• Top End, Cylinder Base and Cam Cover Gaskets
• High Capacity Clutch Springs and Plates

My experience with such a beast was dampened by inclement weather. Constant rain kept my speeds lowered, lean angles in corners leaner and full throttle stoplight launches limited. What I can tell you is that there is no lack of torque here. That extra power comes with and extra price tag is whar Screamin’ Eagle is all about.
There are three Screamin’ Eagle Milwaukee-Eight Stage IV Kit options:
Screamin’ Eagle® Milwaukee-Eight Stage IV Kit (P/N 92500062 Black Highlighted, $2,595.95*) fits 2017-later Touring models equipped with air/oil cooled Milwaukee-Eight 107 engine.
Screamin’ Eagle® Milwaukee-Eight Stage IV Kit (P/N 92500060 Black Highlighted, $2,595.95*) fits 2017-later Touring models equipped with a Twin-Cooled Milwaukee-Eight 107 engine.
Screamin’ Eagle® Milwaukee-Eight Stage IV Kit (P/N 92500064 Black Granite Highlighted, $2,595.95*) fits 2017-later CVO™ Touring models equipped with a Twin-Cooled Milwaukee-Eight 114 engine.