I have a 99 RT that leaks oil from the vent cap on the top of the final drive. It only happens on long trips when the bike is loaded up with extra weight ( camping gear, etc. ) I have made sure the fluid level is at the correct level and that the vent cap is clear and unobstructed. It pukes oil from the vent cap which gets all over the rear rim and sides of the tire which is a PITA to clean up not to mention a possible safety issue. Any insights for a possible cause/fix would be greatly appreciated. Thanks, Gregory