I am not saying I agree but Zero DOES claim it.
When looking at the SR/S on the official website then scroll down a little and it says...
"Inspired by cutting edge aerospace design, the look of the SR/S is rooted in its aerodynamic fairing. Like all things Zero Motorcycles, form follows function. When you lean into the cockpit and get behind the fairing you will be rewarded with a 13% improvement in highway efficiency and range with the SR/S versus its award-winning sibling, the SR/F. Sit up and you’ll discover a more upright and relaxed riding position that feels as good as it looks."
One could argue that you'd have to lie flat on your stomach with legs stretched backwards to get to those 13%