A have a 2001 drz 250 and I was driving down the road maybe doing 50 not that hard in the throttle and it suddenly dropped a lot of speed. So I clutched it and it was still running but as soon as I stoped it died. Oil was coming out of the front right side where the jug meets the tranny. I think it has lost compression. I am familiar with car engines and have rebuilt them. I am unfimiliar with dirtbike engines. Help!! What do you think it is. It will not run. I am not afraid to to rebuild it so help please.