Gear / Parts Harley Screamin' Eagle 128/131 Stage IV Kits Released: 121 Horsepower

Harley Screamin’ Eagle 128/131 Stage IV Kits Released: 121 Horsepower

Harley-Davidson’s new Screamin’ Eagle Stage IV kits for 2017 and newer Touring platforms carry the tagline “Go Big or Go Home.”

And for a good reason. The Milwaukee-Eight platforms grow substantially with these Stage IV kits, the 107CI growing to 128CI (2097cc), and the 114 and 117 to 131CI (2146cc).

And with this increase in CC arrives some serious horsepower gains. The 128 produces a maximum of 126 ft/lbs of torque, and the 131 creates 131 ft/lbs of torque.

Harley Screamin' Eagle 128/131 Stage IV Kits Released: 121 Horsepower

Screamin’ Eagle Stage IV Kit: Transform Your 107 to 128

Features new CNC-ported heads with 1mm bigger valves than the previous generation, and fully machined combustion chambers.

The kit includes a high-lift SE8-517 cam, high compression pistons, and a 64mm throttle body and intake manifold.

When paired with the Screamin’ Eagle Street Cannon Muffler, the 128 Stage IV kit creates 126 ft/lbs of torque and 121 rear-wheel horsepower.

Harley says it’s “designed to run at high-end RPMs and provide a significant boost of torque from cruising speed. You’ll feel the difference as soon as you twist the throttle.”

Harley-Davidson Screamin’ Eagle 128 Stage IV Kit Includes:

  • Screamin’ Eagle CNC Ported Cylinder Head with CNC machined chamber and 1mm larger valves than the previous generation
  • 128 Stage IV Timer cover
  • SE8-517 High-Lift Cam
  • Forged High Compression Pistons
  • Screamin’ Eagle High-Performance Cam Bearing
  • Screamin’ Eagle High-Performance Tappets
  • Screamin’ Eagle 4.31″ Steel Sleeve Cylinders
  • Screamin’ Eagle 64mm Throttle Body and Cast Manifold
  • Screamin’ Eagle High Flow Injectors (5.5 g/sec)

Screamin’ Eagle Stage IV Kit: Transform Your 114 or 117 to 131

With the largest displacement of any Harley-Davidson Stage Kit, this 114/117 to 131 Stage IV Kit was designed to deliver maximum horsepower – all the way to the redline.

Packaged with patent-protected cylinder technology, it allows for the biggest Harley-Davidson bolt-on engine upgrade to any Milwaukee-Eight motor.

The kit arrives with new CNC-ported heads with 1mm bigger valves than the previous generation and fully machined combustion chambers.

It also includes a high-lift SE8-517 cam, high compression pistons, and a 64mm throttle body and intake manifold.

When combined with Screamin’ Eagle Street Cannon Mufflers, it creates 131 ft/lbs of torque and 121 rear-wheel horsepower.

Harley-Davidson Screamin’ Eagle 131 Stage IV Kit Includes:

  • Screamin’ Eagle CNC Ported Cylinder Head with CNC machined chamber and 1mm larger valves than the previous generation
  • 131 Stage IV Timer cover
  • SE8-517 High-Lift Cam
  • Forged High Compression Pistons
  • Screamin’ Eagle High-Performance Cam Bearing
  • Screamin’ Eagle High-Performance Tappets
  • Screamin’ Eagle 4.31″ Steel Sleeve Cylinders
  • Screamin’ Eagle 64mm Throttle Body and Cast Manifold
  • Screamin’ Eagle High Flow Injectors (5.5 g/sec)

Both kits are eligible for Custom Coverage under the motorcycle’s factory 24-month vehicle limited warranty. The coverage is only eligible when the kits are dealer-installed by an authorized H-D Dealer within 60 days of purchase. Otherwise, the kits are backed by a 12-month limited warranty.

For additional information, including fitment, visit H-D.com.

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