This is because the caliper is a cheap s**t design - if the caliper is in good order, i.e. it is not binding on the pins, then the pressure will be the same on both sets of pads - however, the sliding pins seize up and consequently, the piston pad does all the moving. If you take the caliper off, and squeeze the pads together, you will see what I mean. Just more crappy "built-to-a-price" engineering!
BTW, changed my rear pads a7 6200 miles - both worn evenly ('cos I stripped and copaslipped everything) there was at least 0.002 mm of pad left!!
All the best
Jan
PS anyone going to the bike show @ NEC this year?
