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The Fuel Moto M8 128" big bore kit is a complete bolt on engine kit for stock engine cases that makes exceptional horsepower and torque. It includes 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. This kit works on 2017-later H-D Milwaukee-Eight 114" & 117" (4.5" stroke) air cooled & twin cooled engines and when combined with the appropriate performance modifications offers output in excess of 140+ horsepower. This kit works with stock or aftermarket cylinder heads, it requires larger throttle body, injectors, exhaust system, as well as other components that will support 140+Hp. Comprehensive tuning is also necessary, Dynojet Power Vision & Target Tune is recommended, FM has excellent base maps available!
These forged pistons from CP Carillo are available in 10.75:1, 11.0:1, or 11.5:1 compression ratio. The ring end gap is already set ready to be installed.
The Fuel Moto M8 128" big bore kit includes new Extreme Duty cylinders with high strength ductile iron sleeves, bore/hone finish work is done on OEM level machinery to exact tolerances. Cylinders are available in black with silver polished highlights or CVO granite finish with polished highlights. Manufactured by S&S Cycle in Viola, WI USA
The camshaft is the workhorse of any big bore kit which is why every single Fuel Moto big bore kit includes your choice of camshaft from Wood Performance, S&S Cycle, Andrews, Cycle-Rama, Zippers Redshift, Star Racing along with the appropriate compression ratio. Some cams as noted require hi lift valve springs (Additional purchase required, not included with kit).
We all want more power with a big bore kit but would never want to sacrifice reliability. The S&S Cycle Hydraulic Precision 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.
The Fuel Moto quick install adjustable pushrods are the finest pushrods available. Chromoly design which is engineered for maximum strength and durability these pushrods install right inside of the stock pushrod tube covers.
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.
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.
You will need an exhaust system, air cleaner, EFI tuner, clutch, and other peripherals to support the appropriate power level of this kit. Larger fuel injectors are also required. 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. These engines also require comprehensive tuning, we will supply the appropriate FM base tune. 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 as well as our Terms & Conditions
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, injectors or other associated parts such as oil & filter)
