The A.P.E. Silverback 128ci Package is the flagship naturally aspirated Alpha Performance Engines package for Harley-Davidson Milwaukee-Eight riders chasing maximum horsepower and top-end performance.

This is not the mild option. Silverback is designed for riders who want an aggressive, high-output M8 package capable of 160+ horsepower potential with the right supporting components and tuning.

Motorcycle gear shift knob shaped like a black 8-ball on a metallic engine background.

What is the A.P.E silberback?

The Silverback is a drop-on 128ci big bore package for riders who want serious naturally aspirated performance.
  • 128ci big bore capacity.
  • Ported cylinder heads.
  • Extra compression.
  • Large camshaft profile.
  • Upgraded valve train components.
  • Larger throttle body and injector support.
  • High-performance supporting hardware.
A rebuilt flywheel is highly recommended for Silverback-style builds due to the level of performance involved.
Man working on a blue motorcycle in a dimly lit garage or workshop.

who is silverback best for?

  • Maximum naturally aspirated Harley M8 performance.
  • 160+ horsepower potential.
  • Strong top-end rush.
  • Aggressive throttle response.
  • A serious custom or performance build.
  • A package above Street Performer and Sneaky Pete.
Black custom motorcycle with chrome engine parts and dual exhaust pipes against wooden background.

COMPARING A.P.E. ENGINE PACKAGES: SILVERBACK VS. SNEAKY PETE

Deciding between the A.P.E. Silverback and Sneaky Pete comes down to how aggressive you want your Harley's engine build to be. While Sneaky Pete offers high-output street performance with impressive acceleration and big road numbers, Silverback represents the absolute peak of naturally aspirated power for riders seeking maximum performance. Compare key features below to see which package delivers the right level of power for your build.
Feature A.P.E. Silverback A.P.E. Sneaky Pete
Upgrade Type Drop-On 128ci Big Bore Package High-Performance Big Bore Build
Primary Focus Maximum naturally aspirated performance Serious street performance & stronger acceleration
Cam Options Large Camshaft Profile & Upgraded Valve Train High-Performance / Aggressive Cam Profiles
Best For Riders demanding the ultimate, most aggressive NA package Riders seeking a strong road bike with big performance numbers
Main Benefit Peak performance capability and raw engine power Strong road performance without maximum NA aggression
Man working on a blue motorcycle in a dimly lit garage or workshop.

silverback supporting upgrades?

  • High-flow exhaust.
  • High-flow air cleaner.
  • Larger throttle body.
  • Upgraded injectors.
  • Cam chest upgrades.
  • Clutch upgrade.
  • Oil pump inspection or upgrade.
  • Professional dyno tuning.
  • Flywheel rebuild where recommended.
Close-up of a shiny chrome motorcycle engine with black and gold flame-painted fuel tank.

why choose taverner motorsports?

A cam upgrade is not just about installing the most aggressive cam available. The right result depends on matching the cam to your exhaust, intake, engine size and how you ride. Taverner Motorsports can help you choose the best A.P.E. cam profile for your Harley and future upgrade plans.
Discuss my Silverback build

Testimonials

Gave me a great deal on some nice grips and installed them for me, great customer service. will definitely be visiting whenever i need service for my harley

James Southam

QLD

I purchased my Talaria Sting electric bike from Brian. The team at Taverner Motorsports where helpful and ensured that my bike was ready for pick up. I would highly recommend!

Banos Porter

QLD

Great guys, honest, knowledgeable and do great work at more than reasonable rates. Thanks for the work on my CX

Damian Joyce

QLD

I visited the place when I was in Brisbane and I was very well taken care of! I recommend!

Fabiano Sena

QLD

Could not recommend highly enough. Took on my 18 year old Buell. Expert mechanics with great attention to detail and the comms from Brian was second to none.

Leigh A

QLD

Couldn’t have been happier with the work i recently had done to my 2017 breakout . Expert advice and experts on the tools quick turnaround on Christmas week ! Thanks so much Joe and Cat 👍

feidhlim corr

QLD

I had an absolutely excellent experience, my bike came back in better condition than i dropped it off to them.. extremely happy with the customer service and workmanship.

Danny Meredith

QLD

Great people. Diverse bikes in the shop. You can tell they are not snobs and just real motorcycle people

Carlo A

QLD

I recently had my Harley Davidson Sportster serviced and was thoroughly impressed with the work performed by the them. I am extremely satisfied and highly recommend their services to anyone seeking top-notch maintenance.

Abhi Singh

QLD

Definitely recommended easy to deal with Clear, responsive and understanding Of what I wanted and was stoked with the outcome Honestly, Joe and cat thanks heaps again

SKYHAWK SANDO

QLD

Awesome people who are extremely knowledgeable and experienced and very fair pricing.
Had my 883 serviced once before somewhere else, however after the Taverner service I realised how it was meant to run!

Magdalena

QLD

FAQ’s

Some of our most commonly asked questions are answered here. For other queries please contact us directly, so our team can assist you.

What is the A.P.E. Silverback?

Is Silverback suitable for daily riding?

Does Silverback require ported heads?

Is Silverback more powerful than Sneaky Pete?

Does Silverback need a flywheel rebuild?

Does Silverback need dyno tuning?

PERFORMANCE DRIVEN HARLEY SERVICE & BUILDS

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