thanks for all the help.I may have to send them away if I can't crack it my self.Must be all the coffee I've drunk today! (The Campag Service Centre seems to be something to do with Downland Cycles in Canterbury. I've not used them but I know they're pretty meticulous about their fettling, and wouldn't hesitate to let them touch my bike/componentry should I not be able to sort the issue out myself.)