For many bikes, battery range is more important that total power (because they're all pretty powerful). You want a bike that delivers a range long enough for your rides at the power levels you want. Most e-bikes will have three to five levels of assist kicking in anywhere from 25 percent of you pedal power to 200 percent boost. Consider how fast the battery takes to recharge, especially if you'll be using your bike for long commutes.
In the year 1885, a British man named J.K. Stanley introduced what can fairly be described as the first modern bicycle. His Rover bike had wheels of equal size in the front and back and used a chain connecting the pedals and the rear wheel as a propulsion system. It was often marketed as a safety bike in contrast with the unstable Penny Farthing, and was a smashing success. The company went on to develop motorcycles and automobiles, remaining in business until the year 2005.
It’s impressive just how traditional a finish they’ve achieved for a pedal-assist bike, especially considering the motor uses Kinetic Energy Recovery to charge itself (like F1 Cars). Firing up the motor is achieved by back-pedaling three times (while travelling over 8mph). It’s a neat idea, and a clever way of doing away with those cables and switches, but in reality it’s fiddly. Riding in the city we occasionally felt ridiculous on a busy street pedaling backward rather than forward to kick off the assist. It’s also a chore getting the bike to speed and going through the motion to activate in tight spaces such as underground garages or on an incline.
The G-10 features a top-tube mounted on-off button and ‘set’ button for one of four power modes, all linked to a Groove Go wheel mounted motor via a removable clip-lock battery stashed under the down-tube. Kalkhoff has paired this with a mid-range Shimano Tiagra 1x10 speed drive-train and effective Shimano M396 hydraulic disc brakes. A nice touch is the anti-slip ‘grip-tape’-covered flat pedals, perfect for a bike to be ridden around town without specialist shoes.
As electric bike options continue to expand, more brands are integrating the battery more seamlessly. That makes them look sleeker (and more like a real bike). Batteries are expensive, so make sure there's a good way lock the battery to your bike if you'll be keeping it outside. Overall weight is important. Some battery and motors can add 15 pounds or more to the bike. With assist, you won't feel that much when you're riding, but you will if you have to carry your bike up stairs or lift it onto a bike rack.