Head Gasket Question

[jski]

I am in the process of doing the top end on a 1987 CR-500 and noticed that the cooling passages on the head gasket are restricted on all of the passages except on the exhaust side of the cylinder? Now on my 2000 CR-500 all of the cooling passages were restricted but not as much as with the 1987 head gasket. Why the change and why restrict the water flow at all?

 

[Durt Cycler]

I guess the gasket is designed to help flow the coolant better in the topend since it's a big ol' 500 cylinder...? :confused:

 

[Glitch]

I was wondering the same thing when I was doing the top end on my 1987 CR125. The passages where about 4.5mm except for the one on the exhaust side where it didnt restrict anything. I assume that this was the design of the older cr's.

 

[Luke Davey]

This could be to keep all the cylinder and head at one temperature so that these components do not warp or mis-shape. This is the same in car motors, maby a techie can answer this

 

[jski]

Thanks for the replies. I called Forward Motion and they explained that when the gasket changed from the paper to the metal head gasket Honda changed the cooling flow allowing for more pressure and better cooling so by restricting the flow it keeps the fluid in the radiator longer thus providing better cooling.

 

[Durt Cycler]

Ok I'm confused was I right? :confused:

 

[David Trustrum]

was I right?

For the definitive answer ask your wife.