New Screamin’ Eagle engine upgrades available for Harley-Davidson’s Softails, tourers

Harley-Davidson has a new set of Screamin’ Eagle engine upgrades available for its latest-generation Softails (2018-and-newer models) and tourers (2017-and-newer models).

There are three kits available here— a Stage IV kit that takes 114/117ci Milwaukee Eight engines to 131ci. There’s also a Stage IV kit that takes 107ci Milwaukee Eight engines to 128ci. Both those kits are aimed at Softails, and they include new cylinder heads with CNC porting and chamber machining, and 1mm oversized valves. They also come with replacement timer cover, a high-lift cam, 10.7:1 high-compression pistons, performance cam bearings, performance tappets, steel sleeve cylinders, new throttle body and cast manifold and high-flow injectors.

Use them with the right mufflers, and the 128ci kit is supposed to deliver 124 horsepower and 127 pound-feet of torque at the rear wheel. The 131ci kit makes 124 rear-wheel horsepower and 135 pound-feet of torque, supposedly.

As for the touring engine upgrade—this is what Harley-Davidson calls a Stage III kit, taking 114ci or 117ci bikes to 122ci; there’s also a Stage III kit taking 107ci bikes to 119ci. These kits come with big-bore bolt-on cylinders, high-compression forged pistons and rings, new cam and cam bearing, and upgraded tappets, a new timer cover and insert, multi-layer coated head gaskets, and most of the other necessary gaskets and seals.

For more information and pricing, your best bet is to contact your local Harley-Davidson dealer. Buying and installing through your local dealer will mean you get to keep your warranty, presumably, and that’s probably A Good Thing on an expensive bike like an H-D tourer. See more deets in the presser below.

Press release

HARLEY-DAVIDSON ANNOUNCES NEW SCREAMIN’ EAGLE® STAGE KITS FOR MY18+ SOFTAIL MODELS AND MY17+ TOURING MODELS

“Go Big or Go Home” With New Screamin’ Eagle® Harley-Davidson® Performance Parts

MILWAUKEE (OCTOBER 8h, 2020) – The all-new Harley-Davidson® Screamin’ Eagle® products for your ride are here to keep the thrills rolling mile after mile. High-flow exhaust kits, performance cams, ultra-powerful Screamin’ Eagle engines and a comprehensive line of upgrades get you to peak exhilaration quickly and smoothly with the power to handle whatever comes.

SCREAMIN’ EAGLE® MILWAUKEE-EIGHT® ENGINE STAGE IV KIT 114CI TO 131CI FOR SELECT SOFTAIL MODELS

With the largest displacement of any Harley-Davidson® Stage Kit, this 114/117CI to 131CI Stage IV Kit was designed to deliver maximum horsepower – all the way to the redline – available now for select Softail models. Packaged with patent-protected cylinder technology, it allows for the largest Harley-Davidson® bolt-on engine upgrade to any Milwaukee-Eight® motor.

The Stage IV Kit features new CNC-ported heads with 1mm bigger valves than the previous generation, and fully machined combustion chambers. Coupled with the kit’s high-lift SE8-517 cam, high compression pistons and a 64mm throttle body and intake manifold, this combination delivers a thrilling 135 ft-lb of torque and 124 HP rear-wheel output when paired with Screamin’ Eagle® Street Cannon Mufflers. 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.

The Screamin’ Eagle 131 Stage IV Kit is eligible for Custom Coverage under the motorcycle’s factory 24-month vehicle limited warranty when dealer-installed by an authorized H-D Dealer within 60 days of vehicle purchase and is otherwise backed by a 12-month limited warranty.

Performance components include:

  • Screamin’ Eagle CNC Ported Cylinder Head with CNC machined chamber and 1mm larger valves than previous generation
  • 131 Stage IV Timer cover
  • SE8-517 High-Lift Cam
  • Forged 10.7:1 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)

Complete fitment information can be found on H-D.com.

SCREAMIN’ EAGLE® MILWAUKEE-EIGHT® ENGINE STAGE IV KIT – 107CI TO 128CI FOR SELECT SOFTAIL MODELS

This Stage IV Kit was designed to deliver maximum horsepower – all the way to the redline – available now for select Softail models and features new CNC-ported heads with 1mm bigger valves than the previous generation, and fully machined combustion chambers.

Coupled with the kit’s high-lift SE8-517 cam, high compression pistons and a 64mm throttle body and intake manifold, this combination delivers a thrilling 127 ft-lb of torque and 124 HP rear-wheel output when paired with Screamin’ Eagle® Street Cannon Mufflers. 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.

The Screamin’ Eagle 128 Stage IV Kit is eligible for Custom Coverage under the motorcycle’s factory 24-month vehicle limited warranty when dealer-installed by an authorized H-D Dealer within 60 days of vehicle purchase and is otherwise backed by a 12-month limited warranty.

Performance components include:

  • Screamin’ Eagle CNC Ported Cylinder Head with CNC machined chamber and 1mm larger valves than previous generation
  • 128 Stage IV Timer cover
  • SE8-517 High-Lift Cam
  • Forged 10.7:1 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)

Complete fitment information can be found on H-D.com.

Screamin’ Eagle® Milwaukee-Eight® Engine Stage III 114CI or 117CI to 122CI Kit and Stage III 107CI to 119CI For MY17+ Touring Models

This Stage III kit has been developed for the rider looking for a solid “seat of the pants” torque increase you can feel every time you roll on the throttle. The bump up in displacement and compression deliver a significant increase in torque and power over stock, all the while restoring the sensation of riding solo when you’re loaded down.

The Stage III 107CI to 119CI upgrade delivers up to 23% more horsepower and 17% more torque and the 114CI to 122CI upgrade increases power by up to 15% and 13% more torque when compared to the Original Equipment engine configurations.

Performance components include:

  • Screamin’ Eagle 4.155 Big Bore Bolt-On Cylinders
  • Forged 11.0:1 High-Compression Pistons and Rings
  • Screamin’ Eagle SE8-447 Torque Cam
  • Screamin’ Eagle High Capacity Tappets
  • Screamin’ Eagle High Performance Cam Bearing
  • Screamin’ Eagle Stage III Timer Cover & Insert
  • Multi-layer coated Head Gaskets
  • Cylinder Base and Cam Cover Gaskets
  • Most necessary gaskets and seals

Screamin’ Eagle® Milwaukee-Eight® Engine Stage III 114CI or 117CI to 122CI Kit is eligible for Custom Coverage under the motorcycle’s factory 24-month vehicle limited warranty when dealer-installed by an authorized H-D Dealer within 60 days of vehicle purchase and is otherwise backed by a 12-month limited warranty.

Stage III and IV Kits comply with noise and emissions standards in all U.S. states other than California on 2017-later Touring Models and select 2018-later Softail Models. Street-compliant statements may not apply to markets outside the United States. The 131CI Stage IV Kit fits ’17-later Touring models equipped with Milwaukee-Eight® 114CI or 117CI engine and ’18-later Softail models equipped with Milwaukee-Eight® 114CI engine. The 128CI Stage IV Kit fits ’17-later Touring models equipped with Milwaukee-Eight® 107CI engine and ’18-later Softail models equipped with Milwaukee-Eight® 107CI engine. Neither kits fit Trike models. ’17-’19 models require separate purchase of High-Capacity Oil Pump P/N 62400248. 17-’18 models require separate purchase of Screamin’ Eagle High-Capacity Clutch Plate Kit P/N 37000258. All models require additional purchase of ECM recalibration with the Screamin’ Eagle Pro Street Tuner for proper installation. See an authorized Harley-Davidson® dealer for details.

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