Copper gasket or not

[PGGuse]

Having installed an Aluminium barrel on my '65 AJS road model 18 short stroke as replacement of the original cast iron one I'm in doubt whether to install the original copper gasket between barrel and the original cylinder head. I measured the liner protrusion slightly different.
Being thankful for any hint - Paul in Frankfurt

[ajscomboman]

I used to run my CS without one but had a very slight weep. Despite lapping it persisted and I went for the gasket, no more weep. I'd say most definitely yes fit it. I have in all my other CS models and no weeps.

[GOLDSTAR]

I have never had a weep from my short stroke head joint sans gasket, as far as I can tell, but the damn 'O' tings on the pushrod tubes do seem to have a limited life! kind regards

[ajscomboman]

I have never had a weep from my short stroke head joint sans gasket, as far as I can tell, but the damn 'O' tings on the pushrod tubes do seem to have a limited life! kind regards

That's where my weep was coming from, got feed up with it seeping from the o ring area. Now that the o rings are surrounded by the copper gasket the seepage is contained.

[bitza]

Is it the quality of the O ring material, after they have been is service a while do they tend to harden slightly and lose the sealing ability,
Perhaps it might be trying engineering suppliers who specialize in high temperature fittings.