Millennium Technologies

M-Spec YZ295 Cylinder Kit for 1999 – 2019 Yamaha YZ250/YZ250X

The Yamaha YZ250 is the most popular 2-Stroke motocross bike ever made. In production since 1974, the evergreen YZ250 engine has remained virtually unchanged since 1999. Over the last 20 years we have serviced thousands of YZ250 cylinders and we have applied all that experience to our new M-Spec YZ295 Cylinder Kit.

The NEW Millennium Technologies M-Spec YZ295 Cylinder Kit uses a brand new 72mm cylinder designed from its inception to have a 5.6mm bigger bore than stock. The is cylinder is plated with our proprietary Nickel Silicon Carbide Plating process and then ported by hand with a port developed by our own Supercross/Motocross Championship winning Director of Technology, Tom Morgan. The kit comes complete with a forged 72mm piston kit, Cometic gasket kit, a NEW cylinder head and NEW power valve modified to specifically to work with the M-Spec YZ295.

No Core, No Wait.

Everything you need to make your YZ250 equal or better than modern 450cc 4-strokes!

Kit Includes: 72mm M-Spec Cylinder, M-Spec Cylinder Head, M-Spec Power Valve, 72mm Forged Piston Kit, Cometic Gasket Kit.


- Retail $1199.95

- Part #: MK220BB

- OEM Bore Size 66.4mm

- M-Spec Bore Size 72mm (+5.6mm)

- M-Spec Displacement 295cc

R1 Chamber

To order, e-mail or call us M-F 8:30 AM. - 5:00 PM. CST.

Phone #: (920)893-5595