This Stage IV Kit was developed to deliver maximum horsepower from the Milwaukee-Eight® engine - all the way to the redline. The system-matched combination of larger displacement cylinders, free flowing CNC-Ported cylinder heads and a cam with the highest available valve lift are the starting point to building the perfect engine for the performance junkie. Designed for a high level of flexibility, this package is ideal for riders who like to comfortably cruise at lower rpm but still have plenty of arm-pulling acceleration when you whack the throttle. Kit includes CNC Ported Cylinder Heads with Performance Valve Springs, 64mm Throttle Body, High Flow Injectors (5.5g/s), 4.075" Bolt-On Cylinders, Forged 11:1 High Compression Aluminum Coated Pistons and Rings, SE8-515 Cam, Cam Bearing Upgrade, High Performance Tappets, Multi-layer Coated Head Gaskets, High Capacity Clutch Springs (1200N), High Capacity Clutch Disks and most necessary gaskets and seals.
- Stage IV Kit 107CI to 114CI - Air/Oil-Cooled
- Black with Highlighted Fins - Matches Original Equipment non-CVO™ models
- Delivers up to 52% more power when compared to the Original Equipment engine configurations
- Delivers increased response throughout the entire RPM range
- Maintains flat torque curve from cruising RPM to redline
- Can be installed without removing the engine from the chassis
- Retains Original Equipment Factory Warranty
Dealer Install RecommendedYes
Warranty1 year limited warranty – Go to www.h-d.com/warranty for full details
Requires ECM CalibrationYes
Certifications50-State U.S. EPA compliant
Sold in UnitEach
In The BoxClick the Description tab above for details
Sold SeparatelyClick the Fitment tab above for details
Upgrade Stage LevelStage IV
Fits '18-later Softail® and '17-later Touring models equipped with air/oil cooled 107CI Milwaukee-Eight® engine. Does not fit Trike models. Requires separate purchase of Cam Drive Retention Kit P/N 25566-06. Installation may require Cam Spacer Kit P/N 25928-06. For ’17-’18 Touring models, installation of Oil Pump Cover P/N 62400206 is recommended (sold separately). All models require ECM calibration with Screamin' Eagle® Pro Street Tuner for proper installation. Pending approval for use in California on '20 models. Refer to H-D®.com/shop for status.
- Deluxe FLDE
- Fat Boy FLFB
- Heritage Classic FLHC
- Sport Glide FLSB
- Softail Slim FLSL
- Street Bob FXBB
- Breakout FXBR
- Fat Bob FXFB
- Low Rider FXLR
- Road King FLHR
- Road King Special FLHRXS
- Electra Glide Ultra Classic FLHTCU
- Street Glide FLHX
- Street Glide Special FLHXS
- Road Glide FLTRX
- Road Glide Special FLTRXS
Bike not listed?
Select your year and model to see all the parts that fit your bike.
- These Screamin' Eagle® products are 50-state street-legal for sale and use on all vehicles, including those that are pollution controlled. Complies with the requirements of 40 CFR Part 86, subparts E and F.
When installed by an authorized Harley-Davidson® Dealer at the time of vehicle delivery, compliant kits do not impact the vehicle’s limited warranty.
Q & A
What would the suggested labor be for this install?
Why does this not fit on a 2016 breakout?
I want to update my review is there a way to do so?
FLHXS Milwaukee 8 stage IV kit
Why can't you put a Stage IV kit on a tri-glide with a M8 engine? It's the same engine as an Ultra limited or street glide!
Please Hold Your Iron Horses