help if you can please: I´ve tried 3 gaskets and 2 different covers(including the original) on my ´78 cb400t valve cover, it still leaks oil out the front at the seal when running--only possible thing I can think of is that the relief tube on the top of the cover seems a little resistant when you take it off the valve cover and blow in it(should it be 100% easily blown through?), otherwise I am stumped-cover/gasket appear to fit snug, but still leaks, no way it could have been bent, valve head is not warped..this happened after reassembly with a new head gasket, all is positively reassembled correctly, runs great--what´s up with this 2-bolt vavlve cover?!?!?