timnsr250se wrote:oh and the lower cylinder head was on a lot looser than the top head, is it possible it was just too loose , so that the coolant was able to flow through it?
thanks again,
tim

Strewth mate!!
Yes its possible the head was on "too loose". As both heads should be tight as per specified torque settings.Why were they loose? DO NOT just put new head gaskets on as you need new piston kits too.
Throw your single ring pistons in a skip as some t*** has fitted race ones that wont last very long. Although they might last long enough to take all the coating off the bores when they nip up.