I know we're not engineers, but as industrial designers, we should take a minute to read up on the general physical rules of motorcycle steering. Not to say there aren't any creative ways to get around conventional motorcycle forks, take the Dodge Tomahawk for example:
It splits the wheel in half, with each half pivoting vertically to create a lean/turning condition. Check the video to see it in action.
Also check this link for more conventional motorcycle steering setups
This isn't meant to be picking on anyone, I just want our designs to be as informed as possible
Here is the Hub Center steering setup that Tim is looking at for inspiration