Replying to Sponsorship Advice

Riverboarding was recently featured on the front page of the Wall Street Journal. When we show up in any city and ride, we draw huge crowds. We have no problems getting the television and print media to do stories on the sport when we go to any city. With all this exposure, I would think that there would be another company that would want to partner with us. We have tried for years and years to get a sponsorship. We get nowhere. Last year Mountain Dew had an ad campaign called "It's Different on the Mountain". Guess what Mountain Dew, surfing is different on the Mountain. We would have loved to send them some standing wave surfing and bungee riverboarding footage. But no one would talk to us. For summer 2013 we hope to have a tour through 7 states and hit 15 rivers. We will set up television and newspaper/magazine interviews along the way. We really need a sponsor for this tour. Doesn't this sport get enough exposure to warrant a sponsorship? Articles/stories on riverboarding have also appeared in the NY Times, Denver Post, Sacramento Bee, ESPN, Idaho Statesman and many more.