Laminated "copper" head gasket

I've never seen that, but I do know Juice moto parts sells copper gaskets
http://juicemotoparts.com/products/...gasket-set-for-motorized-bicycle-engines.html

The head gasket alone though cost $11. I would think the copper gaskets would hold up better than the aluminum and supposedly can be re-used quite a bit more.

I got the Juice copper head and base gaskets in mine and bought a few of both thicknesses he offers so I could dial in my squish clearance, they seal up perfectly and you're right, they can be reused over and over by annealing them before reinstalling. If I need to use more than one gasket at the head or base I'll "glue" them together with some of that Indian Head gasket shellac right before installing, most of it will squeeze out during torquing and the little bit that's left ensures a perfect seal between the layers.

that ebay one looks more like one of those copper/paper/copper type that can only be used once and they also look way too thick...

i got something like these with a new cylinder that i ordered... i've had it off a number of times so far and had no issues with reusing it or with the thickness factor... seems to work pretty well...

I bought a couple, but not used them.I ended up making my own copper
head gasket.Those are about .025 thick, if I remember right.I made my
own .015 to adjust the squish area.

I did not know anyone made thin ones.

Fly

I bought mine from Juice's site when I was setting up my squish since he makes them either .025" or .016" thick for the head and base so I got 2 of each size so I could put the jug on the block where I wanted it and get my squish into the acceptable range. I chucked my jug on my lathe and cut .056" off the top (took over .040" just to get it straight and true after setting it up for zero runout on the lathe) Then I flipped it around and took off .040" from the bottom to true it up as well. That's why I'm using the combo of gasket thicknesses to set the squish. I could still fine tune it even more by taking a few thousandths off the top or bottom of the jug, but it works so well it's not worth messing with again. My squish clearance came out to 0.75mm (.030") when I called it good. I've heard you can set it as tight as .010" or .25mm, but anything under 1mm is considered good and my compression ratio is already as high as I'm comfortable with for 93 octane.

I can cut out my own gaskets too with my cnc router, but decided to do the exhaust, intake, mag cover, and clutch cover since Juice already does a really good job making the head and base gaskets and I can get the copper sheet at a decent price in .008", .015" .030", .060", and .120". I've cut out a few copper gaskets from the .120" sheet and they work really well once they're annealed, they can all be reused by annealing them before installing, and it's dead easy to anneal the copper, just heat it up red hot then drop into cool water as soon as it's glowing red. I've also tried just letting it cool on it's own and slow cooling, all 3 methods work pretty much the same and it leaves the copper ultra dead soft.

I still need to play with my cutting process on the cnc since the copper does work harden quick enough that it can cut one .120" thick exhaust gasket and about halfway thru the second one before it work hardens enough to start chattering the end mills, so right now the process is still too slow to make them available to sell for a decent price, but eventually I'll get it there. Another great material for gaskets is dead soft aluminum but finding a good inexpensive suorce for the sheet stock in the right thicknesses is the real challenge there. Dead soft aluminum does have a few drawbacks like it can be smashed too flat to use if overtorqued, it can be reused, but limited to about 3 or 4 times compared to copper that can be reused indefinitely as long as it's annealed each time and not damaged, the copper ones can also be torqued down tighter because it holds it's shape and work hardens.