Cool Heads?

[oldsking86]

Alright I'm looking to get a coolhead for my 86 R, Question is do I need to have the motor bored over or a stroker kit to use one? My bike is stock. Also how exactlly do the domes work inside the coolhead, Does it like increase your CC or something to give more power?

[3leggeddog]

you can buy different size domes to change compression.the domes are pressed into the head,and seal with an o ring.i have one,and while it's not a ahuge performance mod,they look cool,and seem to make the bike run cooler.i like mine.

[SYKO]

your engine displacemant comes from piston size and rod length, ask yamahondman about your head

CHECK YO HEAD FOO!!

[TimSr]

your engine displacemant comes from piston size and rod length, ask yamahondman about your head

CHECK YO HEAD FOO!!

Actually the rod length does not change displacment. Its the stroke which is determined by the crank.

[SYKO]

well thats what I ment I had a dumb moment there tim lol!

[deathman53]

I like cool head on a trx, but not atc. The spark plug goes straight up in the center, right where the rail is on a atc, its hard to get the plug in, even worse ifyou are using a spacer plate motor. When I got my 310pv, I had them make a dome that was like the stock head spark plug angle.

[oldsking86]

Yea I guess it would definetly run cooler but I don't want anymore of a pain to get to my spark plug....
Thanks syko & Tim for the confusion, geesh lol
I raise the compression a bit and get some hp im sure, not much; guess i just need to wait and go for the good ole 310 or 350 kit