thanks again for the replies.
But ive stripped the bike- ran it - and no oil to be seen anywhere.
Cooler seems fine with no signs of fresh or old oil leaking.
Iv'e given the bike a good run up and down the bypass near where i live- and she seems fine now.
I can only think that some oil has come through the breathers and into the air box and was just draining away.
anyway i'll keep you posted if it happens again- ansd the cause off it.
cheers degre7
