Problem now sorted - on checking I found a small oil leak from the crank breather gasket, which I've been meaning to fix for ages, was running down the back of the engine and getting into dodgy some very dodgy connections which plugged straight into the old style switch. New switch fitted that connects directly into the loom without the old style link wire and a new seal fitted on breather unit and the problem is now well sorted.
Thanks for the info received - goes to show switches on Ducatis do not always pack up - it was the wiring!sing:
