Front rotor
Front rotor.
The front disc brake rotor is a perforated metal plate attached to the wheel hub. The reduction in speed of the bike occurs as a result of the compression of the brake disc by the pads, which are driven by cable tension (in mechanical type systems) or by means of a hydraulic circuit (in hydraulic disc brakes). The diameter of the front rotor can vary from 140mm to 220mm. The higher the number, the more efficient the brake is.
Rear rotor
Rear rotor.
An element of a disc brake system mounted on the hub of the rear wheel of a bicycle. It is to him that the pads are pressed when the brake lever is pressed. The use of a rotor ensures high braking efficiency. And it is higher, the larger the diameter of the rear rotor. Disc rotors are available in sizes 140, 160, 180, 185, 203 and 220 mm.
Rear derailleur
Model of the derailleur (derailer) installed on the rear wheel cassette as standard on the bike. For more information on why you need to know the model of a particular bicycle component, see paragraph "Cassette Model".
Max range
The maximum range of an e-bike (see "Application") is the maximum distance that it can be ridden using the electric motor on a single battery charge.
Usually, the characteristics indicate the range at the most economical way to use the battery: in the pedal assist mode (see "Operating modes") and at a relatively low speed. Accordingly, in fact, this parameter may turn out to be lower than the claimed one, especially if you drive in full electric mode. Nevertheless, in terms of power reserve, it is quite possible to evaluate and compare various models with each other.
Note that it makes sense to specifically look for a model with a power reserve
of more than 50 km if long trips are planned without recharging along the way. For episodic rides, you can pay attention to cars
with less battery life — they are simpler and cheaper.
Battery capacity
The capacity of the battery that the e-bike is equipped with (see "Application"), expressed in watt-hours.
The main modern unit of capacity is the ampere-hour, but this designation is not entirely reliable: the actual capacity of the battery is determined not only by ampere-hours, but also by the operating voltage. In fact, this means that two batteries with the same Ah and different voltages will have different actual capacities. In order to take this nuance into account, the designation in watt-hours was introduced: it is as reliable as possible, in terms of capacity in Wh, you can compare batteries with any nominal voltage. In this case, Wh can be converted to Ah and vice versa using a special formula if the battery voltage is known.
See "Battery Capacity" above for details on capacity in general.
Max speed
The maximum speed that the e-bike can reach (see "Application").
The specific meaning of this parameter depends on the supported modes of operation (see below). If the machine has a full-fledged electric traction mode, the maximum speed is given at the maximum speed of the electric motor. If only pedaling assistance is supported, then this paragraph indicates the speed that is guaranteed to be kept on it for an unlimited time without applying excessive effort; in some areas you can go faster, but for a long time it will not be possible to maintain this mode.
Most modern e-bikes have a top speed
of up to 25 km/h, but there are also
faster models.
