Electric Bike: Pedal Assist and Everything else
4th Nov 2022
At first glance, an electric bicycle seems to be a regular, human-powered bicycle. The distinction between the two goes beyond appearances—add a motor, hydraulic brakes, a lithium-ion battery, and a throttle, and you've got an e-bike. So, how do all those moving pieces collaborate to propel you up steep hills or lift large loads? Let's go through everything that goes into making an electric bike tick, and then we'll get to the bottom of the burning question: how does an electric bike work?
What Exactly Is An Electric Bike?
An electric bike, like a regular bicycle, has two wheels, a seat, and pedals, but it is additionally propelled by a motor, battery, and/or throttle. E-bikes have grown in popularity in major cities because the cost of an electric bike makes it a cost-effective alternative to driving. Even folks who live in more remote locations have discovered that electric bikes are a quick and easy way to get to the store or commute to work.
A simple electric bike features a pedal assist. The motor engages and propels you ahead as you press the pedals. E-bikes may reach speeds of up to 15-20 miles per hour. While it may appear to be a leisurely pace, it is actually rather fast and may reduce your journey in half (especially if you regularly deal with traffic snarls).
The Elements of an Electric Bike
Some electric bikes include a rechargeable battery (one that recharges as you pedal), integrated lights to make night rides safer, and sleek fenders. While these are wonderful to have, they are not essential components of an electric bike. Every e-bike requires a powerful engine, a battery, a sturdy frame, and brakes.
Motor
Not all electric bike motors are made equal. A hub motor and a mid-drive motor are the two most prevalent types of motors. A hub motor is located on either the front or rear wheel. Hub motors are less expensive, but the ride isn't as smooth. A mid-drive motor is situated in the center of the bike and is linked to the pedal sprocket. A mid-drive motor shifts the center of gravity to, well, the center!
Your e-bike's overall efficiency and longevity will be affected by the sort of motor it has.
Front Hub Drive: The front hub-drive motor is located on the front wheel. Because the back tire already bears a lot of weight, having the motor on the front wheel helps to balance out the center of gravity. A torque sensor, which is a form of throttle that monitors how much electricity to deliver to the motor depending on how fast you pedal, is also used with a front hub drive.
Rear Hub-Drive: As the name implies, the rear hub drive motor is located on the back wheel. It provides more traction, but it is less efficient than a front hub-drive motor. Flat tires are also more common since road debris isn't driven away by the front wheels as it would be if the hub was on the front.
Mid-Drive Motor: This electric motor is located near the pedals, in the "middle" of the bike. If you have a mid-drive engine, you can quickly change flat tires, and you can even use regular bike tires if you choose. A mid-drive motor e-bike has a far better gear ratio, which means you can shift into a lower gear as you travel upward. Mid-drive motors function in conjunction with electric-assist systems such as torque sensors, cadence sensors, and throttles.
Battery
The battery powers the motor, which is responsible for getting you where you need to go! The majority of e-bike batteries contain 350-500 watts of power. You also can't use any old battery on an e-bike. It should be both lightweight and strong so that it does not drag you down. Older e-bike versions often include lead batteries, which do not store as much power and are hefty. Instead, go for a lithium-ion battery.
Although lithium-ion batteries are light, they are costly. Some people prefer nickel-cadmium batteries (also known as "nicad" batteries). Because they can power your bike for 10-40 kilometers on a single charge, lithium-ions are the gold standard. It takes around 3-6 hours to recharge. If your battery dies while you're riding, you can always ride your bike manually. Never underestimate the distance you can cover on pure pedal power!
How do the batteries function? It is determined by the sort of e-bike you own:
Pedal Assist Power: Pedalling starts the motor, increasing your speed and power. As the pedals slow, the bike's speed drops. This is a popular form of e-bike since riders can still choose how much power they get from the motor—in other words, they aren't letting the bike do all the work.
Electric-Only Bikes: Powered by a throttle, electric-only bikes require no human force to move. These e-bikes exhaust the battery rapidly and need stricter safety rules.
Drivetrain and Frame
A standard bike's frame is often composed of aluminium alloy, making it incredibly lightweight and efficient. The same holds true for high-end e-bikes: the lighter the frame, the quicker the bike. Because an e-bike has additional torque, the spokes should be sturdy enough to prevent bending or breaking (power moving it forward). Look for spokes made of chrome, steel, or brass.
The pedals, cranks, chainrings, chain, and cogs are all part of the drivetrain. All of these components work together to propel your e-bike forward. A mid-drive motor directly drives the drivetrain, allowing you to swap gears and pedal more easily. It's another reason why mid-drive motors are popular among riders who prioritize efficiency.
Brakes
E-bikes and traditional bicycles both have brakes. However, because e-bikes are more powerful and quicker, their brakes must be more robust than those found on standard bicycles. The e-bike community prefers hydraulic disc brakes. They come to a complete halt in any weather. Riding an e-bike with hydraulic brakes is safe.
Rim brakes, sometimes known as cable brakes, need low maintenance and provide adequate stopping force, although not as well as hydraulic disc brakes.
Pedal Assistance Systems
The pedals, or more precisely, your feet on the pedals, power a pedal-assist bike. In contrast, the initial generation of e-bikes was primarily powered by throttles, which were often located on the handlebars. Simply twisting the throttle or pressing a button gives your bike power!
Pedal-assist devices are becoming more common as electric bikes gain popularity. Electric assist systems are an essential component of pedal-assist bikes. An electric-assistance system delivers power to the powertrain via the pedals rather than the throttle. Electric assistance systems are classified into two types: cadence sensors and torque sensors.
Cadence sensors function as a throttle that is driven by your feet. A sensor monitors the movement of a magnet attached to the pedals while you ride your electric bike. The sensor then effectively "tells" the motor to switch on. It detects your speed and notifies the motor how much power to provide as a consequence. This, however, has clear drawbacks. When you travel uphill, the cadence sensor detects that you are moving more slowly and instructs the motor to provide less power, which is just what you need.
Torque sensors are the most recent advancement. They monitor how firmly your feet press down on the pedals. The sensor determines how much power to transmit to the drivetrain based on your pedal pressure. You can probably predict how fast and efficient your rides will be if your bicycle includes both a cadence sensor and a torque sensor.
You're ready to test out an electric bike now that you've learned everything there is to know about them! Your key priorities should be safety, durability, and efficiency. To obtain your money's worth, be sure the bike has high-quality brakes, a long-lasting battery, and an efficient power system. And, of course, while you're out on the road, always wear a helmet.