Head gasket confusion

[MalcW]

Hi, I recently bought copper head gaskets 022236C for a 1959 500 twin. They were annealed and fitted with new viton O rings, but we had trouble with heavy oil leaks from the head to barrel joint, as per a separate topic I posted recently. Following suggestions there, and in the forum elsewhere, I bought 022236 composite gaskets. However, they are too tight by a few thou to fit over the lip at the top of the bore. Is this a known fault, or is it the wrong gasket? Is it possible to file the copper sleeve of the composite gasket to open it out a bit, or isn't there enough metal? Could you use viton rings with a composite gasket? I haven't on my 650 and haven't had any issues.

Thanks,

Malc

[dave16mct]

It's a difficult one to answer without seeing it. Are you sure you haven't got '60 on heads and barrells? The '60 on heads have the cross fins underneath. They have 77.34mm spigots, the '59 have 76mm spigots. Perhaps you could put some pictures on which would be a great help. Is it 1960 model registered in late 1959?
Dave.

[MalcW]

Hi Dave, thanks for the quick response. The spigot on this one measures 76.66mm across according to my vernier, and that corresponds with the cutaway in the head. The head doesn't have the cross fins; I know what they're like as my 650 has them. It just seemed odd that the 022236C copper gasket cleared the spigot cleanly but the 022236 composite one doesn't.

Cheers,

Malc

[dave16mct]

In that case I would say that the gaskets are wrongly sized and should be returned. The next size down is for pre '56 500 twins and is 72.8mm. So there is no mistake in model or year. They're just undersize. You can't file them down as the copper is very thin. Very frustrating for you.
Dave.

[MalcW]

In that case I would say that the gaskets are wrongly sized and should be returned. The next size down is for pre '56 500 twins and is 72.8mm. So there is no mistake in model or year. They're just undersize. You can't file them down as the copper is very thin. Very frustrating for you.
Dave.

Hi Dave

Frustrating indeed, but it is what it is. I can't return them as they are now marked where I tried fitting them, but I can at least now check their replacements before they go anywhere near the bike!

Thanks for your help.

Malc