There are many different components to an e-bike.
Different e-bikes have different type of wheels, gears and frame materials.
So, what are the pros and cons for different equipments?
The size of wheels generally creates different experiences to an e-bikes. Generally there are 20inch and 26inch wheels, some manufactures also do 16inch wheels. Therefore there are pros and cons for the different size wheels.
Generally speaking, the bigger the wheels are the better the ride quality is. As, bigger wheels roll over bumps smoother. Compare to smaller wheels which get into the bumps more distinctly. In addition, larger wheel is more efficient during cruising, as larger wheels have more momentum than smaller ones when cruising. However, this makes them harder to accerate, due to the inertia caused by the larger and heavier wheels.
Smaller wheels are easier to accelerate, due to there isn't as much inertia from the wheels. This makes it better for bikes that requires frequent accleration and decleration. They are more nippy, and they have smaller turning circle. This is due to the wheelbase is generally shorter. Bikes with smaller wheels are also easier to store them, as they are generally on smaller bikes. This makes smaller wheels more common than larger wheels on foldable-ebikes.
Different types of frame also have pros and cons. They are mainly differentiate by the material used. There are steel frames, aluminum frames and carbon fiber frames.
At the very begining, the frames are generally made by steel. One of the advantage of steel is that it is very rugged. In addition, steel frame should be quite comfortable. As, it is great absorbing vibrations from the road. There is of course disadvantage from using steel, steel frame is heavier than the other two options, which would not be optimum for e-bike. Thus, they are less common in recent years.
Then, there are aluminium frames. The advantages of aluminium frames are that they are relativly light, and they are easier to produce in comparison to carbon fiber. This material is quite common in recent years producing bikes.
Lastly, there are carbon fiber frames. It is lightest out of all three material, and a great benefits of carbon fiber is that is can be make into a lot different shape. Thus, the manufacture can make the frame very stream line , and therefore very aerodynamic. The disadvantages are also very significant, it is not cheap nor very rugged. It is toward the expansive end of all three materials, and if there is an accident on carbon fiber bikes, the damage might be not as significant visible and there might be mistakenly thought as no issues there.
There are two types of gears for bikes in general, there are internal hub and derailleur gear, both types are used on e-bike
This type of gear is a bit easier to use for everyday usage, it is a bit more forgiving. It is more reliable than the derailleur gears, there is also less tuning required for this type of gear. This make this type of gear quite common on urban bikes. The disadvantage for this gear is that it cannot handle as much torque as the derailleur gear. So, this type of gear is generally used on urban bike which generally take less aggressive riding.
This type of gear is very commonly used these days, is generally fitted on advance bikes such as mountain bikes or road bikes. The advantage is that it can change gear while there is large amount of torque. This makes it great for bikes with more aggressive riding. The disadvantages are that it takes more tuning with the usage of the bike. It is also a little bit less forgiving to use this gear, for example you should not change gear while not padelling.