Compared to gas engine bikes such as mopeds, electric engines run slower. They are also sluggish in cold weather when the electric engines are less responsive.
Some electric bikes have "power assist" engines, only giving a boost when the driver is pedaling. This can be exhausting for the driver. There are newer, power-on-demand electric bikes that don't require pedaling at all. However, some electric bike riders only want a bit of help on hills and prefer the authentic feel of pedaling.
The crank drive motor allows the bike to shift gears, which older hub motors did not. However, crank drive motors can be bulky and unattractive.
Hub motors are located in the hub of the wheel on an electric bike and there are no moving parts. They are more attractive and smaller than crank motors. Early hub motors did not allow the use of gears, although that technology is developing. The brushes in a hub motor may wear down, requiring overhaul.
Like many rechargeable devices, the rechargeable batteries in electric bikes fail, necessitating a replacement battery.
Some electric bikes, particularly those that look more like a moped than a bike, are criticized for the unattractive look, heavy weight and impractical pedals. Skeptics wonder if they are not simply electric mopeds, never intended for pedaling.
