1986-1989 Honda TRX250 FourTrax 250R Service Manual, Page 188Get this manual
HYDRAULIC DISC BRAKES DISASSEMBLY
Remove the pad springRemove th caliper pivot collar and boots
(3) PAD SPRING
Position the caliper with the pistons down and apply small squirts of air pressure to the fluid inlet to remove the pistons
Do not use highpressureairor bring the nozzle too close to the inlet Place shop towel over the piston to prevent thepistonsfrom becoming projectile
Push the dust and piston seals in and lift them outClean the seal grooves with clean brake fluid