Anyone who owns a bicycle can use the Asus Oxiis E250G1 Intelligent Bike Booster to transform it into an e-bike in just a few simple steps. Equipped with a cadence sensor, it is designed to respond just as quickly as a conventional e-bike, and can be charged via a USB-C charger.
These types of devices get an automatic pass from me: I’d rather just have a powered hub wheel that can be swapped in, a normal bike with good gearing, or a dedicated e-bike. I usually just stick with a regular bicycle but I do love my Portola too.