To cap it all!
When I had my tyres fitted the guy who balanced the wheels complained that the centre caps would not come off and asked me to take them off - he didn't want to break them, so I did. Looks like they were glued onto the wheels. Great for staying put but not so good when you want them balanced. The upshot is that I had 4 damaged caps that I tried to stick back on with something less sticky - well now I have three as one fell off and got lost :-( I took the others off and have been trying to get replacements. The caps are plastic with a 58mm diameter, 32mm tall and have fixings that are 7mm deep with a 4.5 mm recess in them. Anyone got any ideas where to get some from?