So i took the bike out for a long trail ride today. After trying to keep up with my buddies dirtbike after awhile we stopped to let the, both cool down a bit. well when we started back up i only had 3rd gear. I know they are sticking but wondering what could cause this. Could it be from getting to hot. I havent changed the oil since i bought it 4 days ago but i know the guy put 10w- 30 in it.