I agree that the hub on my bike looks like the Sportive model but I'm still getting 1:3.1 ratio. Can you check your bike (and can a Shimano owner check their bike)? Just raise up the back wheel and put the hub in the lowest gear and measure how many times the wheel turns when you turn the crank one time (I get 1.4 rotations). Ditto in the highest gear (I get 4.4 rotations). 4.4/1.4=3.14. Maybe I have an adjustment problem in that the hub is not going to the lowest and/or highest gear. If you believe the gear chart above the Current with the Enviolo hub should have the wheel turn 1 time for 1 crank rotation when in the lowest gear position (assuming I understand gear-inches) and ~ 4 rotations in the highest gear.