Coming back from a ride, I found my front brakes were graunchy at slow speed. Suspecting a seized piston had caused one pad to wear thin, I whipped out all the pads but all was well. Then I found the problem got worse, so I suspected gravel in a caliper and checked the discs for scratching. One face was indeed scratched, so I pulled the pads for that face. Some idiot (me) had replaced that pad the wrong way round. You'd think it would be impossibIe to do that and have the pin fit properly but clearly not. Luckily not much harm done...
