Just to share my math in case I did something wrong.
RPM * pi * diameter = linear speed
so
90(pi)(340) = 96,132mm
96,132 = 0.0597 miles.
and here’s where I discovered my mistake. That’s .06 miles per minute not MPH.
So
.06(60) = 3.6 MPH
90(pi)(330) = 93,305
93,305 = .058 MPM
.058(60) = 3.48 MPH
I think everything else works out the same.