I have a low mileage 78 R 100/7 that is leaking oil around the top head bolt and running down around the spark plug. I have just replaced the head gasket and retourqed the head but it is still leaking. When I installed the new gasket I put a thin coat of copper coat on it.
Is this a cracked head, or does this year of bike have some strange quirk that I am not aware of?
How does the oil get to the top of the head to leak at this point?