From the Sram E groupset article on the main page
Someone needs to work on their understanding of torque and gear ratios because this is nonsense
Look at your cassette. Down at the bottom you have 11 then 13 teeth – a 2 step difference. At the other end on the big rings you can jump from 36 to 44, because at this end your legs will be pushing high torque at higher RPM so you can deal with the big jump in teeth. If you look at the profile of your cassette you’ll see it’s a curve. Power output from your legs is not linear and so this curve in the cassette profile kind of matches what your legs can do. There are lots of variables and lots of riders ride their bikes in different ways but the important thing to note is that fact that the human body puts out different amounts of torque at different RPM.
The difference in ratios between one gear and the next is linear – or as close as it can be given that sprockets need to be whole numbers.
11 speed 10-42 cassette 10-12-14-16-18-21-24-28-32-36-42
12-14 is a 17% jump. 36 to 42 is also a 17% jump
8 speed 11-48 “e-cassette” 11, 13, 15, 18, 24, 32, 40, 48
11-13 is an 18% jump 40 to 48 is a 20% jump
Car gearing – with a lot more power than a Bosch electric motor – works exactly the same
Also torque?
You have the same amount of torque available at the cranks regardless of the gear you are in its the maximum force your leg muscles can produce in Newtons multiplied by the length of the crank arm in metres. Torque at the back tyre does vary based upon the mechanical ratio you are getting from the gears but it doesn’t really have anything to do with the amount of torque a rider can produce at the cranks