Originally Posted by
joejack951
That's a big assumption (unless you have some proof to back it up). I can believe that a rim goes out of round when a load is applied to the hub. However, the only way to apply a load to the bottom of a rim by using a hub attached to the rim with spokes is to pull down on the rim (you can't push with a spoke). The only spokes that can provide that pulling force are the spokes at the top.
And in order for the rim to go greatly out of round at the bottom, the spokes next to those bottom spokes would need to stretch (increase in tension) to allow for the out of roundness (the material of the rim has to go somewhere). All of this is complicated by how many spokes are used, the cross section of those spokes, and the cross section of the rim. I need to go and read Brandt analysis and see exactly what he modeled and measured though.
Sorry, but you're wrong. This has been argued a million times. Pretensioned structures behave differently.