CRF Head differences

[patrickj75]

I'm getting ready to buy a new OEM head for my 06 CRF motor. Are there any differences from 02-08?

[blacknblue#2]

Im pretty sure 02-04 heads are the same with 05-08 heads being the same...Keep in mind the 2007-2008 cams are different due to the decompressor unit. Dont quote me on this tho. Just a rough memory thought

[patrickj75]

Ok. I believe my decomprsion unit is from an 05 or 06. I think I'll just get an 06 head to be safe.

[JH Racing]

02-03 head had 31mm ex valves and 04-08 had 30mm ex valves the port lay out changed some through the years but all the heads will interchange the decomp set up has no effect on the head just cam and tower

[fmfhonda250r]

02-06 have 36/31 valves. The 07/08 have 36/30 valves.
Here is a link showing that 02-06 use the same ex valve.
http://www.cheapcycleparts.com/products/356383-honda-14721-meb-670-hard-parts-valve-ex

[patrickj75]

I ended up buying an 08 head. THe port design is supposed to be better than 02-06. It was only $25 more than an 06 head.