Ok, I am very experience with working on gearboxes, but this has me stumped. I shimmed, and put a m130 spring in my v2 src gearbox( already has other upgrades) and whenever I put the motor in it doesn't pull back the spring it just clicks. I have took the gearbox apart twice, switch the wires on the motor, turn the motor 180 degrees. The ARL is ok to, I check that. Please help I don't have a clue. Oh the motor is a jg blue. Also I full charged 9.6v battery.