YZ125  Kit includes
1 head body, 2 domes, 1 o-ring kit
5 copper washers
Head brackets 2005-2010

Order your kit from parts listed below

1994-2000 Head body
2001-2004 Head body
2005-2010 Head body

OS2 o-ring kit same as OEM o-rings

YB3 Head Brackets 1994

YB4 Head Brackets 2005+

OEM 1994-2004 radius top piston
Dome selection (see note)
Y11 10.0cc
Y12 9.3cc
Y13 8.8cc
Y14 8.1cc

OEM 2005-2010 flat top piston
Dome selection (see note)
F11 7.8cc
F12 6.9cc
F13 6.0cc
F14 5.2cc

Note
Heads colors are red, blue, black, gold and aluminum
YZ125 1994-2004 stock with radius top piston
YZ125 2005-2010 stock with flat top piston
Flat top or Radius top pistons will work in all YZ125 provided matching dome is used
Y11 domes are closest to stock compression 1994-2004
F11 domes are closest to stock compression 2005-2010
Y1 and F1 series domes use o-ring seal, the max bore is 58mm
Dome modification for big bore available see FAQ