I just replaced my first gear cause I stripped it. I put it all back together and now the brakes lock. You cannot move it at all. I tried loosening the screws that hold the pads on but it didnt work. Also, when i spin on eof the rear wheels, it makes this bad stripping sound where the bevel gear is. WHat should I do? I really need some help. I am not sure if I am missing any parts or not.