anyone know how much the compression changes with an xr head gasket?

[Selland74]

anybody have any numbers on this?

thanks

[GOTFEAR]

have you taken dial calipers and messured the 400 and the xr to see how mutch of a defrence their is. i think .020 is around a half of a point on compression on a low compression piston

[Selland74]

i think i read that an xr gasket is . 010 thinner than the ex gasket.

[flauge]

Aint the base gaskets on them thinner too?? I though they were.:confused:

[400exstud]

Originally posted by GOTFEAR
i think .020 is around a half of a point on compression on a low compression piston

Might be right for one tiny range; however, pressure increases on an exponential scale as the distance between the end points decreases.

[Selland74]

i should specify a little bit. stock piston, top gasket only. it sounds unreasonable but ive heard if you put a drz400 (suzuki dirt bike) gasket on a z400 it goes from like 11:1 to 13:1. sounds like a little much to me. but im not sure