Upgrade Your Harley-Davidson M8 Performance with Alpha Performance Engines Big Bore Kits
Ready to take your Harley-Davidson Milwaukee-Eight (M8) to the next level? Discover the Alpha Performance Engines (APE) Big Bore Kits at Taverner Motorsports—Brisbane’s trusted workshop for motorcycle engine upgrades and Australia-wide shipping. Whether you’re chasing more horsepower, torque, or a smoother, more exhilarating ride, our APE kits are engineered for riders who demand the best in Harley-Davidson M8 performance. If you want dyno tuning in Brisbane or reliable support anywhere in Australia, you’re in the right place.


Why Choose Alpha Performance Engines Big Bore Kits?
Precision Engineering:
Designed specifically for Harley-Davidson M8 engines, each APE kit is crafted for bolt-on simplicity, durability, and maximum power gains.
Trusted Brand Reputation:
Alpha Performance Engines is a recognised leader in Australian motorcycle performance; Taverner Motorsports brings years of expertise and friendly, professional service.
Proven Dyno Results:
All kits are dyno tested for real-world performance, with horsepower and torque figures that speak for themselves.
Comprehensive Support:
From quoting to installation, tuning, and after-sales service, our Brisbane workshop and nationwide team have you covered.
Product Range: Detailed Kit Descriptions

Stump Puller 128” – Value & Torque
The Stump Puller 128” kit is your entry to serious low-end grunt and all-day rideability. Perfect for upgrading 114” and 117” M8 engines, this package features robust APE cylinders, forged pistons, and the CR485 cam—delivering smooth torque and power that’s friendly on pump fuel. Loved by touring riders and daily commuters alike, it’s the ideal blend of durability and value.

Sneaky Pete 124"/128" – Balanced Performance
The Sneaky Pete is a favourite among Harley-Davidson owners chasing balanced power and reliability. Available in 124” and 128” configurations, this kit offers over 150 horsepower and torque-rich delivery, making every throttle input a thrill. Designed for ride-in/ride-out upgrades, APE’s engineering ensures dyno-tuned excellence, whether you’re cruising or carving through Brisbane’s hinterland roads.

Silverback 128” – Maximum Horsepower
For adrenaline seekers and those who want to push their Harley to the limit, the Silverback 128” package is unmatched. Producing a dyno-proven 160+ horsepower, this is the kit for serious performance enthusiasts. Engineered for strength and reliability, you can expect massive acceleration and a grin-inducing riding experience every time.
Performance Gains: Dyno Results & Real-World Benefits
Horsepower & Torque:
Horsepower & Torque: The APE Sneaky Pete delivers 150 hp+, while the Silverback pushes 160+ hp. Expect substantial torque gains for stronger launches and effortless overtaking.
Smoother Acceleration:
Enhanced throttle response and a power delivery that makes every ride more enjoyable, whether in the city or on the open highway.
Reliability:
All kits are engineered for everyday usability, balancing high performance with long-term durability and minimal maintenance.
Dyno-Tuned Results:
Benefit from precision tuning for optimum results, ensuring your engine performs at its peak.

Installation & Dyno Tuning Services
At Taverner Motorsports, our Brisbane workshop offers full installation and dyno tuning for all Alpha Performance Engines Big Bore Kits. Here’s how the process works:
- Select Your Kit: Choose between the Stump Puller, Sneaky Pete, or Silverback—depending on your riding goals and bike model.
- Order & Booking: Order online or contact our team to book your installation. We offer flexible scheduling for Brisbane locals and can arrange shipping Australia-wide.
- Professional Installation: Our experienced technicians handle everything from disassembly to fitting new cylinders, pistons, and cams. We maintain stock heads for simplicity, with optional ported upgrades for more airflow and power.
- Ride-In/Ride-Out Service: With our Sneaky Pete package, enjoy a seamless experience—drop off your bike, and pick it up fully upgraded!
- Dyno Tuning: Every installation includes comprehensive dyno tuning to extract maximum performance and ensure reliability.
- Unlock Your Bike: After installation, you’ll notice smoother acceleration, improved throttle response, and the kind of power that adds serious grin factor to every ride.
Australia-Wide Service: Shipping & Local Expertise
Based in Brisbane, Queensland, Taverner Motorsports supplies and installs APE Big Bore Kits across Greater Brisbane and offers Australia-wide shipping and support. Whether you’re in Sydney, Melbourne, Adelaide, Perth, or anywhere in between, we deliver parts and expertise right to your door. Our team is always available for advice, guidance, and after-sales service—making us the trusted choice for motorcycle engine upgrades Australia-wide.
Testimonials
FAQs
Yes, APE stands for Alpha Performance Engines. Both names refer to the same high-performance kits, and we stock and install the full range.
The Sneaky Pete delivers 150 hp+, while the Silverback can push 160+ hp with dyno-proven results.
Yes, most kits are designed to retain stock heads. Optional ported head upgrades are available for riders seeking more airflow and power.
All Alpha Performance Engines Big Bore Kits are engineered for durability and everyday usability. Regular maintenance and quality installation are key to long-term reliability.
Most installations are completed within a day or two at our Brisbane workshop. Ride-in/ride-out services are available for select packages.
While experienced mechanics may choose to DIY, professional installation and dyno tuning are recommended for optimal results and warranty coverage.
Yes, every installation at Taverner Motorsports includes dyno tuning to maximise performance and reliability.
Absolutely—we offer fast, reliable Australia-wide shipping and ongoing support for all customers.
Contact & Next Steps
Order online, visit our Brisbane workshop, or contact our team for expert advice, quotes, and bookings. Whether you’re after dyno tuning in Brisbane or reliable motorcycle engine upgrades anywhere in Australia, Taverner Motorsports is here to help.
- Order Online: Browse our full range and place your order with Australia-wide shipping.
- Visit Brisbane Workshop: Experience our ride-in/ride-out installation and dyno tuning services.
- Get a Quote: Contact us today to discuss your bike, riding style, and power goals.
- Follow Us: Stay up to date with the latest Harley-Davidson M8 upgrades and performance tips on our social media channels.
Experience the difference with Alpha Performance Engines Big Bore Kits—engineered for serious Harley-Davidson M8 performance, supported by Brisbane’s leading workshop, and shipped anywhere across Australia. Your ride, your power, your way.
Order online or visit our Brisbane workshop. We offer full installation and dyno tuning for optimum results—especially with Sneaky Pete ride-in/ride-out service.