I have a 900s thats about 7 months old now. Ive taken the belt cover on and off several times and have not had any leaks with the factory gasket. I always make sure its flat and not pinched or twisted when reinstalling. I use to fill my belt box up with water to test for leaks but recently had a crankshaft seal fail and i think its cuz water and belt dust stays in that cavity between the engine block and backplate. That area doesnt drain when u pull the plug. Anywho, i hear people using grease on the lip to help seal the cover? Grease doesnt get smushed into the belt housing when you do that? I would use 100% silicone on the lid but i cant get to the bottom of the housing real well with the clutches installed. Almost like i need to pull clutches, put silicone on the gasket, then reinstall clutches and belt then put lid on. I thought about attatching a hose to the caulk tube to get to bottom easier. Any thoughts?