Cylinder Head

This cylinder head will improve the power output of the YZ250 dirt bike. A must for any rider wishing to be a winner on a Yamaha YZ250 mx bike.

VHM produces exchangeable cylinder heads for two-stroke engines in both motocross and road racing. VHM develops products of high quality thanks to their experience gained in two-stroke tuning.

The combustion chamber is simple to change; just untighten the cylinder head, take it off and the combustion chamber can then be changed. This makes it very easy to adjust the combustion ratio to different circuits and fuels that are used. Combustion chambers for unleaded fuel can also be provided.

During intensive tests on the racetrack, there was better temperature development in the cylinder head just as on the VHM testbench.
A lower engine temperature followed. The explanation of this phenomenon is the use of a special aluminum alloy which has a very good heat transference.
Another advantage of the material is it's resistance to detonation. It is also possible to design your own combustion chamber, just take a blind combustion chamber and you can make any type that you want.

A cylinder headset contains a cylinder head, combustion chamber and the necessary O-seals.

The world famous golden VHM head with exchangeable combustion chamber is specially developed for optimal power output during the whole race and has an improved water duct. It's manufactured from a high quality alloy and O-rings are used for the sealing.

Use VHM standard insert (1 x Included):

AE32021-B (YZ250 2008-2025) 
AE32021-092 (YZ250x 2016-2022)

• More engine power
• Better heat transference
• More resistance to detonation