Anyone have a good way to get out mildew stains on the seat and handle bar cushion? I used Star Bright on the seat, took out the black stains, but 2 weeks later the yellow turned gray. I was thinking of using some shoe die to bring back the color. The handle bar cover I've had no success with. It has 1/4" size black dots on it. Ski sat outside uncovered for 2 years befor I bought it. How about restoring the color to the plastic hood?