Tensile hubs - new lightweight cheap eastern express hubs

Water ingression into sealed hubs is a thorny problem which has taxed many brains and there is still no ultimate solution. We have tested slightly larger diameter caps with no noticeable difference. The problem is the width of the gap as dictated by the small lip at the bottom which presses against the inner bearing ring. We have tried reducing that but then there is the problem of production tolerances, which spill over into all the tolerances. The seat of the bearing for instance. Decreased tolerances always means increased price so we are constantly optimising all the parameters. As somebody said, an 'o' ring or sealing washer is another solution but that immediately increases drag, so you compromise again. The quality of the bearings is a factor, but we use NBK bearings which appear to be the best that Taiwan produce. Changing to Japanese bearings would double the price without, according to our tests, vastly increasing the lifespan.
We always try to achieve 'optimum design' and will continue to do so. Any suggestions are therefore always welcome.