So I have a 100D loaner with me for a few days with the new 21” sonic wheels as opposed to the traditional turbines. I noticed this interesting gouge out behind the spokes and it got me thinking whether the new 21” sonics are actually lighter than the previous 21” turbines? Anyone have any data/specs on the new ones? The gouge certainly looked cast on purpose to reduce weight. That and the spokes themselves are slightly thinner than the 21” turbines from 2012-2017.