One last piece of speculation before I resume my probation.
I will believe the "3 Part Wheel" because The red on Big Bang could be a shock absorber in order to reduce the extreme recoil in metal wheels so different types of attack can be executed and defense can be better with other wheels having rubber.
Last time I checked, MFB had pretty much no competitive upper attack combos, thus meaning that with red rubber on Big Bang , this, like said above would reduce the massive recoil with metal on metal contact, thus allowing upper.
Metal on Metal would result in a huge collision, resulting in a knockout (Attack vs Attack or Attack vs Defense) of one or both beys, or if one bey is not knocked out, the other bey would spin for about 5 - 15 seconds depending on the hit or attack power.
So upper attack in MFB is clearly just smash attack with the bey being lower than the other resulting in extreme destabilization. The slants might not even be effective, at least majority of the time. However, there might be one issue.
How would they be able to include or fit rubber on every Metal Wheel? Is it just Big Bang Pegasus? On the small picture of L Drago Destroy, there is no sign rubber from what I've seen. However, like stated in a couple of comments above...
The clear wheels will have metal compounds, which will generally increase weight and maybe even reduce the recoil. Then again, this might mean Metal Wheels won't have 3 parts.... Ah, who knows what will happen. We'll have to wait.
By the way, thanks for the info Kai V