That said, NeilBlanchard has a good summary of the issues. But once you decide to go open wheel, it's only a question of *how*. In this case a Radir spindle mount 12-spoke is a beautiful wheel, it's a shame to cover them up. What spindle does it use? $799? Nevermind.
plasticuser -- My understanding it that it's the front half of the pontoon that applies unwanted side forces to the spindle if it doesn't closely follow the tire contour.
I agree the shape should be asymmetrical. In the case of my VLV design they would be a 1/4 sphere in the inside and almost flat on the outside.
aerohead -- "40 3/4 inches long and 7 1/2 inches wide" suggests a 5.4333 fineness ratio.
HydroJim -- Here's what I think: Open Source
The contact patch of a 12" tire will be short front to back. I think you gain
pi times as much patch area if you increase the diameter instead of the width. I suggest a 3x15" wheel with a 125/15 off the Citroen 2CV.
Sven7 -- Wouldn't you get the most turbulence at a zero yaw angle? With a 'wake filling' effect otherwise?