Hi, I'm after a bit of advice. My son has a airsoft Saw M249 which he has had for about a year. When he brought the gun second hand he had a faster gear set fitted & shimmed with a m130 spring also fitted. The motor runs off a 11.1 lipo battery with no mosfet fitted. We both rewired the gun completely with good quality 18awg silicone wire as the original wire was badly damaged & had a load of fixes where it had broken. The gun came with a nuprol high torque motor which stopped working after a couple of games so we replaced like for like & again the motor has stopped working after a few games. We have taken the motors out of the gearbox when they stopped working & wired them directly to the battery but they are dead so can only think the motors have burnt out (the fuse hasn't blown). We have checked the gearbox for tightnes of gears or jamming gears & all move freely. Is the motor to weak for the workload or is something else wrong. If so please can you advice.as we don't know what could be wrong.