YZ80/85 Kit includes
1 head body, 2 domes, 1 o-ring kit
4 copper washers

Order your kit from parts listed below

1993-2010 Head body

OS7 o-ring kit same as OEM o-rings

Dome selection (see note)
Y01 6.4cc
Y02 6.0cc
Y03 5.6cc
Y04 5.2cc

Note
Heads colors are red, blue, black, gold and aluminum
Y01 dome is closest to stock compression and has a max bore 54.mm
Dome modification for big bore available see FAQ