Just looking on ebay there and there's a set of JCW calipers for sale from minimatt and one of the logos is up the left as someone used alloy wheel cleaner which has probably taken off the lacquer. Sounds just like whats happened to mine, previous owner must have been using alloy wheel cleaner!!
As I said in a previous post, it must have been the previous owner who must have used alloy wheel cleaner which has stripped the lacquer and bit of the paint of the calipers as I have had to touch them up as well!What were you using on your wheels?!
Concentrated sulphric acid?!?!