Same as usual tshirt you get. There is nothing extra in an autograph.

I wouldn't walk across the street if it was being given away ... BUT THERE ARE FANS who just might be interested in it! Obviously, those fans are not here - but will be at superbike messagegroups and exhibitions. THAT'S where you need to advertise your shirt!

it depends on the fans, why dont you put it on ebay or try to sell it in some sport event related to the racing.