Dommi 88 500cc Head Gasket spigotted barrels .

I use a solid copper one on 88SS.  No issues.  Been there a long time.  Annealed each time it's been disturbed.  Probably from RGM.

I once tried a copper gasket but got oil leaks around the pushrod tunnels.  For years I have used the rather tacky ones (can't remember what they are called) but with a PROCEDURE.  That's because the idea of re-torquing after 100 miles did not work. The gasket blew at 80. so my procedure is to re-torque at 50 or 60 miles, and again at 150 and 500 miles. If there is much "give" at 500, I may go as far as re-torquing at 1000.  A hassle as you also need to check the tappets as the head squidges down.  But I get a bullet proof joint.  I have put about 130000 miles on my dommi 88 in 26 years of ownership.  Warning: the edges of the very thin copper, top and bottom of the gasket, can really slice your fingers as you struggle fitting the cylinder head.  John Powell