[Mikey350D]

Anyone know if an '07 head (entire assembly) will work on a '08 CRF250??
Have an '07 head with SS valves, Faction says they're not coming out with SS valves for '08 until May

Thanks

[Asmith]

Anyone know if an '07 head (entire assembly) will work on a '08 CRF250??
Have an '07 head with SS valves, Faction says they're not coming out with SS valves for '08 until May

Thanks

It will work just fine.

BTW - the only valves that are different on the 2008 are the exhaust valves, the intakes are the same on all years. The FactionMX intake stainless valves will fit just fine in the 2008 head.

The 2008 exhaust valves have a smaller stem - 4.5mm, all previous years have the 5.0mm stem.

[ThumperX]

Anyone know if an '07 head (entire assembly) will work on a '08 CRF250??
Have an '07 head with SS valves, Faction says they're not coming out with SS valves for '08 until May

Thanks

It will work just fine.

BTW - the only valves that are different on the 2008 are the exhaust valves, the intakes are the same on all years. The FactionMX intake stainless valves will fit just fine in the 2008 head.

The 2008 exhaust valves have a smaller stem - 4.5mm, all previous years have the 5.0mm stem.

Does a smaller exhaust valve stem benefit anything performance or maintaince wise?

[Asmith]

Anyone know if an '07 head (entire assembly) will work on a '08 CRF250??
Have an '07 head with SS valves, Faction says they're not coming out with SS valves for '08 until May

Thanks

It will work just fine.

BTW - the only valves that are different on the 2008 are the exhaust valves, the intakes are the same on all years. The FactionMX intake stainless valves will fit just fine in the 2008 head.

The 2008 exhaust valves have a smaller stem - 4.5mm, all previous years have the 5.0mm stem.

Does a smaller exhaust valve stem benefit anything performance or maintaince wise?

Less mass. Less valvetrain resistance. Plus+++

Less surface area. More heat retention. Minus---