2006 outlander 800 hot rear cylinder

Been having trouble with my ’06 800. It has 8100 miles on it now but the rear cylinder gets very hot pretty quick from cold start. The front cylinder stays cool but rear cylinder is too hot to touch even after 2 minutes of idling. Don’t want to run it anymore than that I was thinking it could be the oil screen or oil pump? Need some help before I tear apart the motor