If I knew what the problem was I could give it a title!

I have a 1965 650SS and recently removed and stripped the head, replacing valves, springs ..... whilst waiting for parts I also changed all the springs/seals on the gearbox/kickstart side and replaced the entire clutch (completely shot at).After replacing the head, replacing the solid copper head gasket (Andover Norton) all fired up on second kick but as soon as it began to get warm the head gasket started to leak at the back section particularly around the left rear, this position has been changed at some point with a stud and nut. Thinking I had incorrectly fitted the head I changed the gasket - twice, saw no problem with the old one's at all. Correct torques and tightening sequence followed.

Fired up for the second and third time and the same happened again.

After suggestions from the forum I went ahead to have the head skimmed, trying to eliminate any possibility although it did look OK.The oil tank was re-chromed and checked in case something was amiss but all tube work is clear and the oil return is working correctly.

I wrote on the forum, read previous postings which only told me that the heads were notoriously hard to fit and leaks were common - oh joy ... to add to this oil was now leaking from the crancase breather.

I contacted the previous owner - very helpfull - and said to fit the old type composite gasket but in the meantime as I am waiting for delivery I have fitted a softer gasket (RGM) that seems a better fit. I have turned the engine over on the kickstart, no plugs, and the oil is "pouring" out of the crancase breather to the extent that I am reluctant to fire the engine and repeat an oil blowing head.

Somewhere pressure is building up to force the oil through the head and now the crancase breather but I cannot think that anything I have done that could have affected the issues I have now.

The issue I have is that I live in Menorca - no British bikes here, no one to bounce a few ideas off - "Billy no mates" I hear you say.I am not an expert but enough knowledge to carry out the work Ihave done - or as I thought.

Can anyone hazard a guess what may be the cause of the probelm no matter how stupid it maybe so that I can check it out - any shot in the dark will help.

Best regards

David