250r head gaskt help

[william16339]

hey guys im putting back together my 86 250r, and im putting a metal head gasket onit, the gasket kit i bought, came with it.... anyways it looks pretty thin, do you think ill be ok? compression wise? i have a cr250 gasket, im about to get the caliper and measure the thicknesses of the two.. i just dont want to be over 200 psi.. race gas is quite expensive.

if it is too thin, should i run 2 base gaskets to raise it back? thanks- william

BTW stock head-ported PT cylinder..head is not shaved

[DohcBikes]

The thickness of the gasket might be specified on the packaging? "pretty thin" is a relative term, it would be nice to have the actual thickness spec. Do you have a vernier caliper? Could you possibly get the numbers from the website where you ordered the gasket?

I'm no two stroke expert, but adding base gasket thickness will change the port timing. To what degree and how it will affect performance, I do not know.

[3wheelrider]

^^^^^Yes measure the gasket thickness^^^^^How many layers is it?- If its the 3 layer gasket it shouldnt be thin at all. It should measure between .75mm-1mm with all 3 layers of a steel layered gasket. (The center layer thickness varies on some). I run the 2 outer .25mm pieces = .50mm. I am very close to 200psi but not sure the accuracy with the HF tester I have-but seems about right. My head has also been worked tho. Never had a problem luckily runnin pump 93. You may or may not be as lucky.
I dont like the fiber Aftermarket headgaskets at all. They always weep as soon as I fill with coolant. But not with the steel ones. They (fiber) tend to be on the thick side anyway-(1 to 1.3mm).
Just saw you have a CR gasket-Not sure how thick those are or how many layers.

[barnett468]

What was your compression before?

What thickness was that gasket?

What is the distance from the top of the exhaust port to the top of the cylinder?

Is the head stock?

What is the current bore size?