Screamin Eagle Performance Upgrades

Performance Upgrade Offers

Push your performance even further with an upgrade kit, taking that adrenaline rush even further - rider discretion is advised, you might get addicted! This Winter, we're making it easier to take your performance to the next level, and making it even more affordable; is this your self-indulgent Christmas gift?

Anything is possible, from mild to wild. Please call us on 01572 823296 to discuss your idea’s and remember you can save 20% off labour & parts*.

*Free collection radius is limited, Valid between 26/11/20 & 16/02/21

Harley-Davidson Handlebar Upgrade

Milwaukee-Eight Stage II Torque Kit

This kit was developed for the budget-minded rider that wants to experience crisp throttle response and acceleration. The 5% increase in torque can be felt immediately off the line and continues to build by up to a 14% increase @4,500rpm. The ideal power band for passing slower-moving vehicles.

Milwaukee-Eight Stage III 107 to 114 or 114 to 117 Kit

This kit was developed for the rider looking for a solid seat of the pants increase you can feel – every time you roll on the throttle. The increase in displacement and the bump in compression deliver a significant increase in torque and power over stock while restoring the sensation of riding solo when taking that long trip with a passenger and luggage.

  • Delivers up to 39% more power when compared to the Original Equipment engine configuration
  • Delivers increased throttle response throughout the entire RPM range
  • Produces flexible roll-on passing power without a required downshift 


Harley-Davidson Wheels Upgrade
Harley-Davidson Boom Audio Upgrade

Milwaukee-Eight Stage V Kit - 114ci to 131ci

Go big or go home. With the largest displacement of any Harley-Davidson Stage Kit, this 107CI to 128CI Stage IV Kit is designed to deliver maximum horsepower – all the way to the redline. Packaged with patent-protected cylinder technology, it allows for the largest bolt-on engine upgrade to any Milwaukee-Eight motor. Features new CNC-ported heads with 1mm bigger valves 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 135ft-lb of torque and 124 HP rear-wheel output when paired with Screamin' Eagle® Street Cannon Mufflers for 131 kit customers. It’s designed to run wide open 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.

  • Delivers increased response throughout the entire RPM range
  • Provides thrilling acceleration when twisting the throttle
  • Maintains flat torque curve from cruising RPM to redline
  • Can be installed without removing the engine from chassis
  • Includes CNC Ported Cylinder Head with CNC machined chamber and 1mm larger valves, 131 Stage IV Timer cover, SE8-517 High-Lift Cam, Forged High Compression Pistons
  • Also includes High-Performance Cam Bearing and High-Performance Tappets, 4.31" Steel Sleeve Cylinders, 64mm Throttle Body and Cast Manifold, High Flow Injectors (5.5 g/sec)



Get booked in today.

It's easy to book your motorcycle in, through our online booking forms or over the phone.
You can reach our team by calling on 01572 823296.

Central Garage (Uppingham) Limited trading as Sycamore Harley-Davidson is an appointed representative of ITC Compliance Limited which is authorised and regulated by the Financial Conduct Authority (their registration number is 313486). Permitted activities include advising on and arranging general insurance contracts and acting as a credit broker not a lender.

We can introduce you to a limited number of finance providers and may receive a commission from them for the introduction. Terms and Conditions Apply. All finance applications are subject to status, UK residents only, 18s or over, Guarantees may be required.

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