sorry for slow response but went to see my garage with your comments. They have advised me that the calipers are all free. the excess wear is on the offside front (very bad) and the near side rear not so bad. They have been reluctant to replace the master cylinder as car has only done some 52000 miles. (i assume this is quite expensive to do ) They believe this is a design fault with kia cars as they had this problem with other models. please comment.