That's a great question and a common concern when you start dividing up your market. First of all you need to have a hard look at your target market and figure out if it's big enough to make it worth targeting explicitly. That's easy to say but often hard to do. For a lot of startups, "big enough" means that that you can be profitable by having an attainable amount of success in that market. If you can't get profitable with skaters alone you might have to widen your scope. If skaters are a big enough market to be profitable, then you might want to stay there. The problem with going too broadly is you either get little traction at all (most likely) because teens can't figure out what sort of teen your stuff is for. My guess is that most teens wouldn't describe themselves as "typical" so marketing to a "typical" teen might simply alienate everyone. In my experience few products start out with "mass appeal". They get traction within a market and then figure out how to expand from there.