Check to make sure the reverse switch is all the way forward and locked in place. I have a 96 yamaha timberwolf 250 2x4 and sometime if I don't have it all the way to go forward or reverse it won't go in gear. I can cycle through every gear and the neutral light goes out but since its no locked to go forward or reverse it won't move. I hope this helps solve your problem if you haven't already figured out what the problem is