Originally Posted by
deep_sky
I lowered the tension of the spring. You should see a hole towards the rear of the pedal, with a + and - on either side. Try turning to the - side, that should loosen the spring and make it easier to disengage. Start off in very tiny increments until you get it right.
Remember too that the M520s are double-sided, so you need to adjust the tension on each side of each pedal. This fouled me up when I first made the switch.