My 99 WR 400 had always leaked a little bit of oil out the large hose connected to the very top of the valve cover (the one that runs down to the bottom for breathing and venting purposes I suspose). My oil level is always kept at full and apon oil chaanges I always drain both areas and filter along with adding exactly 1.7 quarts of yamalube 10 x 50 oil. Is this a common problem. I have to top up after every full day ride. I My buddy just baught the same bike and did an oil change. After returning from a 60 mile dual sport ride I noticed a oil smell and looked down to see his skid plate with a large amount of oil all over it coming from the same hose as mine does. This kind of leads me to believe that this is a common problem. Any ideas. Weld a screen to the under side of the valve cover, run thicker oil, etc. Help?????????????????? Anyone else having the same problem.