A perplexing situation solved..
I had just done the rollerisation job and been for a blat around the block. When I got back noticed an oil leak on the left side around the head gasket area..
How can this be? Its got new gaskets and yes the dowels are all in place..
A squirt with degreaser and a hose down revealed the oil was running down from further up somewhere.
Pete suggested maybe the o-rings on the spark plug tube were leaking, but there was no visible oil inside that cavity.
I finally found it was leaking from the oil pipe fitting and seeping around the outside of the head gasket, to drip off at the lowest point.
No problem, I'll get some new copper washers for the banjo fitting....
Did that and tightened it up as much as I dared.
Another test ride and still the leak is there. Must be the oil pipe says me!
I removed the pipe completely and it looked fine, no kinks or frays in the webbing.
Sealed the ends with rubber blocks and vice grips, put it in a bucket of water and applied compressed air to the open end.. No leaks..
So the pipe is fine and its got new copper washers and its done up tight but leaks..
At this stage I'm thinking the situation is impossible but then it is an Italian motorcycle and there will be some ridiculous reason for this to occur.
So i screwed the banjo bolt into the head as far as it would go without the hose on it.
Then measured the gap between the head mating surface and the bolt mating surface,
I then measured the banjo end of the pipe plus two copper washers only to find that there was less than 1mm of crush being applied to the washers before the bolt bottomed out in the hole..
So when I thought the bolt was done up tight it was just out of thread (or bottomed in the head) and not actually clamping the copper washers..
Two copper washers on each side - oil leak fixed.. [You must be registered and logged in to see this image.]