Does the RT2 have a head gasket? I just took the cylinder head off mine and found no gasket. There is a copper ring just around the top to the piston but no gasket between the main body of the cylinder and the head. Is that right or do I want to be putting a gasket in there along with the copper ring when I put it back together?

The copper ring is the gasket. 

Yep copper ring does the trick. Could anneal it if ya wanted to help seal better but must admit i've not done that to mine & seals good. Effectively held down in 8 places--i never thought of it like that, till now.

Thank you. So I can use the same gasket multiple times? When might I know that it needs replacing?

Pretty much never. I've just kept using them without issue. Good system. Annealing--softening by heating until 'just' red then quenching in cold water softens it to theoretically help it seal better & allow it to follow any slight imperfections while tightening the head i guess. But i don't recall ever doing mine or needing to. If you overheated the annealing process then it might blister so that'd ruin it.

Good stuff to know... My tank is getting close to MT and I'd like to check my timing... That stubborn ol Mule.. I know... its the nature of the beast!... 
Sneezles61

Just cause I like pictures...
The RT2

 

I've seen that pick on partzilla & don't know why they show a 250 with 360 inset pic. Just to confuse us i guess.