128/131″ STREET FIGHTER

The M8 Street Fighter kit is for the customer wanting to go to a larger cubic engine and do an upgrade or refurbish to the heads. The heads will get new guides, +1mm intake and +1mm exhaust valves, and a performance valve job. These kits feature our 4.312 bore cylinder kits with our custom liners, made from 110,000 PSI ductile iron. These are made longer to support the piston at the bottom of the stroke. Also supplied are the new T-Man Premium High Lift Spring Kit, our custom-made, fully coated Wiseco pistons with 3mm oil ring and top-of-the-line Total Seal Rings. Pair this kit with one of our performance cams for big power and torque on a well-mannered touring bike.

$3,879.88

Price does not include shipping or sales tax

128/131″ Pro Street Touring

These kits feature our 4.312 bore cylinder kits with our custom liners, made from 110,000 PSI ductile iron. These are made longer to support the piston at the bottom of the stroke. Also supplied are the T-Man Premium High Lift Spring Kit, our custom-made, fully coated Wiseco pistons with 3mm oil ring and top-of-the-line Total Seal Rings. The head features our proprietary CNC port work, complete with oversized intake and exhaust valves. Intake and exhaust seats are removed and re-machined for oversized seats to ensure stability. This kit will take a 107″ to a 128″ and a 114″/117″ to a 131″ without any crankcase modifications. With this, you will also have your choice of T-Man cam, which will be determined by the power and torque desired and, more importantly, your riding style.

For more information on your build, you can contact us with any questions you have. We recommend viewing our videos on cylinder liners and external breather kits. Also, be sure to take a look at our Vented Dipstick (a must-have on all big-bore motors).

$4,610.28

Price does not include shipping or sales tax

139/143″ Pro Street 4×2

Introducing our Big Cubic inch, big power touring package. The 139” motor comes standard with our custom-lined cylinders that feature a longer bezel to keep the piston rock down and keep the piston much more stable in the cylinder. The Pro Street 4×2 head is fully CNC ported with all-new intake and exhaust seats, new guides, +4mm intake valves, +2mm exhaust valves, and our Premium High Lift Springs. Pair this kit with one of our performance touring cams and see huge torque and horsepower that jump right up and carry through the RPMs. This kit is perfect for the customer looking for big cubic inch power on a motor that can still be a legitimate pump gas touring bike.

This build does require a full bottom-end service. Below you will find a spec sheet for the top end only and one for the top and bottom end service. If you would like more information on our M8 Bottom End Service, click here for more information.

TOP END SERVICE ONLY

$5,023.21

TOP & BOTTOM END SERVICE ONLY

$10,541.38

Price does not include shipping or sales tax