Today i have been mostly playing with front brake calipers....
Mine has suffered with the usual stickyness, due to a holed gaiter allowing crud to accumulate inside and eventually seize things up.
Ive removed, cleaned, replaced the piston 3 times in the 3 1/2 yrs ive owned my sport.
Managed to pick up a 2nd hand caliper from an M reg sport just before christmas with a view of eventualy getting round to swapping it with the sticky one.
well today was the day, and guess what......it was the wrong size caliper.

Have spoken to the seller, apparently the M reg sport was an German import (Facelift). it didn't have an interior when i went to collect the calliper so it wasn't obvious.
BUT....The piston was the correct size. so removed both pistons,new one and the sticky one, using a bicycle pump! and gaiters. and swapped them over

Fingers crossed that will now see me for a fair few miles

Phil.