M8 124" and 128" Big Bore Kits

M8 120ci Big Bore Kit

Our Fuel Moto 124" and 128" M8  bore kits are true bolt on combinations (no case boring required) and are sold as complete kits with the absolute highest quality components, all of which have been extensively tested in house both on the dynamometer as well as in real world conditions to deliver top level performance. The 124" kit works on 2017-2019 H-D Milwaukee-Eight 107" engines (air cooled & twin cooled) and the 128" kit works on 2017-2019 114 & 117 engines. When combined with the appropriate performance modifications offers output in excess of 140+ horsepower.

 

Contact us at 920-423-3309 with questions or to place your order!

 

The Fuel Moto M8 124" and 128" kits include the following:

 

Custom Fuel Moto / CP Carillo Forged Pistons

Custom Fuel Moto / CP Carillo Forged Pistons

These forged pistons from CP Carillo are available in a specifically customized 11.0:1 compression ratio. The ring end gap is already set ready to be installed.

Fuel Moto Precision Bored Cylinders

New Precision bored cylinders with iron ductile liner

The Fuel Moto M8 124" & 128" big bore kit includes NEW cylinders with a ductile iron sleeve. Cylinders are black with silver highlights.

Wood Performance Knight Prowler Camshaft

Wood Performance Knight Prowler Camshaft

The camshaft is the workhorse of any big bore kit which is why every single Fuel Moto big bore kit has a Wood Performance Knight Prowler camshaft inside. The Wood Performance WM8-408 has been built with this kit in mind and provides a strong power band offering early torque and high end horsepower alike. There are other cam options available, please contact us at 920-423-3309 for details.

Wood Performance M8 Alpha Series Directional Lifters

Wood Performance Alpha Series Directional Lifters

We all want more power with a big bore kit but would never want to sacrifice reliability. The Wood Performance Alpha Series Directional Lifters are a key component which addresses a common concern with the stock lifters which are simply not designed for the increased performance of a big bore kit. We are also a huge advocate of new parts on new parts so with a brand new Wood Performance camshaft we also install the brand new lifters on each and every build we perform in house.

Fuel Moto Quick Install Adjustable Pushrods

Fuel Moto "EZ" Quick Install Adjustable Pushrods

The Fuel Moto quick install adjustable pushrods are the finest pushrods available. Chromoly design for maximum strength and durability these pushrods install right inside of the stock pushrod tube covers.

All Necessary Gaskets, O-Rings and Torrington Style Inner Cam Bearings

All Necessary Gaskets, O-Rings and a Torrington Style Inner Cam Bearing

No one wants to be in the middle of a build and find that they are missing a gasket or o-ring to complete their build. With the Fuel Moto big bore kits all the necessary gaskets, o-rings and inner cam bearing are included. We have already performed in house stress tests to find the best performing parts to ensure your build is reliable for years to come.

Unlimited Technical Support From Fuel Moto

Unlimited Technical Support From Fuel Moto

You have done all of your research but maybe you still have a question. The technicians at Fuel Moto have the answers and would welcome your call. With every Fuel Moto big bore kit purchase we include unlimited technical support. Shoot us an email at info@fuelmotousa.com or give us a call at 920-423-3309 - we will work together to get you up and running.

What else do I need?

You will need an exhaust system, air cleaner, EFI tuner, and clutch spring and/or lockup to support the appropriate power level of this kit. Milwaukee-8 engines also require larger fuel injectors. Fuel Moto engine kits require installation by a qualified mechanic with experience in engine building and the appropriate tools to check all clearances & tolerances during engine assembly following the OEM service manual procedures and any additional instructions provided. You will need a OEM service manual and some specialty tools such as a inner cam bearing removal/install tool. Check our FM University site for helpful tips and info.

 

Professional turn key Installation:

starting at $3099.00* at our location including the complete kit, break in & dyno tune on our state of the art dyno. (*does not include EFI tuning device, exhaust system, throttle body, valve springs, injectors or other associated parts such as oil & filter)


 

Screamin' Eagle High-Flow Injector Kit - Milwaukee-Eight Engine (5.5 G/Sec)

High-Flow Injectors

Milwaukee-8 big bore kits require larger than stock fuel injectors. Fuel Moto carries a wide range of injectors for assorted applications. 

 

Wood Performance BW-4V Valve Springs

Wood Performance BW-4V Valve Springs 

We all want more power with a big bore kit but would never want to sacrifice reliability. The Wood Performance BW-4V Valve Springs prevent additional stress from utilizing a higher lifter camshaft.

Fuel Moto / AIM Variable Pressure Clutch

Fuel Moto / AIM Variable Pressure Clutch 

The Fuel Moto / AIM variable pressure clutch is the most cost effective and powerful kit available to upgrade your H-D stock clutch to handle the added power of the Fuel Moto big bore kit. Developed by Fuel Moto with a specific weight combination to suit our engine packages this clutch will support 135+ horsepower / torque with the upgraded springs.

Dynojet Power Vision

Dynojet Power Vision 

The Dynojet Power Vision is a flash based fuel tuning tool which allows your motorcycle to be properly re-tuned for your Fuel Moto big bore kit and other performance modifications. We offer base fuel maps and continued fuel map support for your big bore kit with the Power Vision at no additional cost.

Jackpot M8 2/1/2 Head Pipe

Jackpot M8 XXX and 2/1/2 Head Pipes 

The Jackpot Milwaukee-Eight Head Pipes are designed specifically for the tuning & performance characteristics of the new Harley-Davidson Milwaukee-Eight. Fuel Moto has spent countless hours developing our head pipe and our systems continue to be the highest quality, best performing head pipes on the market! The Jackpot XXX and 2/1/2 head pipes accept the factory M8 heat shields. 

Fuel Moto M8 Cylinder Head Porting

Fuel Moto M8 Cylinder Head Porting 

The Fuel Moto M8 Level A and Level B CNC cylinder heads were developed through dyno & extensive flowbench testing to deliver maximum performance on hi-output H-D Milwaukee-Eight engines. The Fuel Moto heads are CNC ported and are best suited to 117" & larger engines developing 130-160 horsepower.