Dear Jo, last year at scrutineering I was asked the question about my 125, " Are you intending to do something about your back tyre?", to which my answer was " Like what?". Scrutineers answer " Fit a new one", My answer, " That IS a new one". Scrutineers answer " Well, Ive been told they've got to have one and a half millimetre of tread on them" my answer " 125 tyres barely have one and a half millimetre of tread when theyre new". And thats a fact that I told thm in the 1980's when I used to ride the 180. It obviously takes a long time to sink in!!! So , according to this rule 125 tyres are worn out before they've even been fitted!!!! Lets just say, commonsense prevailed on these occasions