Originally Posted by Retro Grouch
Depends on the individual wheels. Some 3 spoke in the past, for example, have had roundness problems. I'd imagine that a cast metal wheel would have a serious weight penalty compared to a wire spoked wheel.
Not always my old lester mag rims for my bmx were magnesium 7 "spoke" And weight about the same if not a little less than my spoked alloy rims. That was on my mx though. Magnesium is heavy than aluminum so lighter but ccast rims non spoked are possible. I think the main reason weve not seen them in road bikes is they havve a distinct aero disadvantage. To have like but strong mags like a bmx you have to make them the same way. This includes the I beem like structure of the spokes of the mag. With out the I beem shape the first corner you take would snap the ring away from the spokes and that would be all she wrote.
Skyway mags use to be made froma special plastic and had dozens of paterns 4 5 7 8 and spider web to name a few they were much lighter than any spoked rim but would fex under high loads. On a road bike or any thing above 24 inch youd be in almost constant flex.
That why other than spoked rims in road bike you only see carbon fiber rims and wheel sets.