Forum

[Andy C]

Composite or copper?

When I built my 612 originally I used a copper head gasket and never had any issues, when I did the rebuild after I bought the bike back I fitted a composite gasket which I notice has begun to weep a little.

The thinking was that the composite gasket would give a better seal.

So composite or copper- or have I answered my own question?

[PeteF]

I've had good success with composite head gaskets with a smear of Wellseal.

[Adrian]

The alternative is to go gasket-less if that doesn't bump your compression up too far, with the barrel machine for a couple of O rings around the top of the push-rod tunnels.

A.

[Meteorstorm]

I sprayed the gasket with Copperspray on my 612cc,never saw any inkling of a weep .

[PeteF]

It is important to get the mating surfaces as clea, flat and scratch free as possible. Wet and dry on a sheet of MDF suffices.

[stinkwheel]

I used the composite with flame ring too and there's a smidge of a weep. I've been using composites on my 350 for a while now and they have been very good.

I do notice the 350 ones have a built-in ring of sealant round the pushrod tunnels which is absent on the 500/535 one.