eBike 101
OUR MOTOR
The Bafang, Ultra Mid Drive Motor is Bafang’s new generation motor. Therefore, unlike previously constructed Bafang Motors such as the BBSHD and BBSO2, it is the only motor equipped with a torque sensor, in addition to cadence and speed sensors. This highly sensitive torque sensor tells the Ultra Motor how much pressure is being applied to the pedals allowing it to respond with an equal amount of power in return. Thus the more pressure applied, the more power returned. This makes your ebike ride feel natural, rather than having a non-controlled amount of power delivered when the pedals are turned.
The Ultra motor delivers power instantaneously as the rider begins pedaling, unlike the delayed response, due to the absence of the torque sensor, in the Bafang BBSHD and BBSO2 models. Likewise, the torque sensor instanttaneously shuts off the power supply when the rider stops pedaling, allowing for much better handling, and safer riding on technical terrain.
The Ultra motor is built bigger, and beefier, than it’s predecessors, and therefore, considered to be more durable. Refer to the side by side comparison of the Ultra to the BBSHD, illustrating this size difference.
When it comes to the amount of power the Ultra delivers, when compared to other torque sensing mid drives, there is really no comparison. The power delivered by the Ultra motor is second to none. However, despite this industry leading power output, the torque sensor in the Ultra motor allows for less battery consumption due to efficiency in power output.
Last but not least, Bafang encases their new generation torque-sensing motor, with a thick cast aluminum case, built to withstand the beating of off-road riding. Test ride one today at a dealer near you.
RANGE EXPLAINED
How to Figure Out Electric Bike Range
The range of an electric bike is how far you can ride on one charge. The problem is how to assess electric bike range. All electric bikes are advertised as having a particular range. However, these advertised ranges are usually inaccurate. In fact, sometimes they are downright exaggerated, and may even be four times higher than the reality. It is nearly impossible for electric bike range claims to be totally accurate. There are too many factors that make it different from person to person.
Factors to consider:
- How much the rider weighs;
- What level of assistance the rider chooses;
- The terrain they’re cycling over;
- The amount of luggage they’re carrying;
- How fast they go (1/3 faster = 1/2 the range);
- How hard they’re pedaling;
- How many times they stop and start (hill starts in particular will drain power);
- Wind conditions;
- Temperature (they will get about 15% more range from a battery on a warm sunny day than they would in winter);
- Tire pressure (as with regular bikes, soft tires = less efficiency = less distance for power expended);
- What kind of battery they’re using;
- How old their battery is (batteries lose power over time);
- Size of their bike motor (big motors are fun, but obviously they drain more battery power); and
- How fast they’re going.
How to Figure Out Electric Bike Range
Most people will want to have the most powerful bike motor they can afford. But in fact, motor power only impacts how fast you can pull off, and how well you can get up hills. It does not necessarily impact how far you can go. The most important variable to look at in terms of electric bike range is battery capacity.
The size of the battery is directly analogous to the size of a car’s gas tank.
Battery capacity is usually measured in Watt-hrs. Watt-hrs = amp-hrs x volts.
Note: when you are looking at adverts for electric bikes, you may find some where battery capacity is simply stated in amp-hrs. This is insufficient, as it does not include the voltage, so it does not reflect the true energy capacity. So if a bike is advertised with a 36 volt battery, with a capacity of 9 amp hrs, then the true capacity of the battery is 9 x 36, that is, 324 watt hrs (written as 324 Wh).
Watt-hrs is important, because watt-hrs determine the range of your bike, that is, how far you can go.
For example:
Bike A has a 24 Volts and 20 AH battery = 480 watt hours.
Bike B has a 48 Volts and 10 AH battery = 480 watt hours.
Bike C has a 24 Volts and 6 AH battery = 144 watt hours.
Bikes A and B have a similar amount of energy. If Bike A and Bike B have equal motors and riders, they will perform in a very similar fashion. The bike with the higher voltage battery will accelerate faster and climb better – but that will be at the expense of some of that energy. On the other hand, Bike C will not take you nearly as far.
Simply put, if you want an ebike that accelerates fast, climbs well, and can travel long distances on a single charge, then buy one with a battery that has high voltage and high amp hours. A battery with high voltage and low amp hours will shorten the distance you can travel on a single charge.
Also consider the issue of range with regard to the type of motor you are buying. For example, there is a good argument that mid drive motors get a better range than hub drive motors because they work synergistically with the gears.
Mid-Drive vs Hub Motor
When purchasing an electric bike, the first thing to consider is the motor, and quite frankly, a mid-drive motor trumps a hub-drive motor in almost everything but price. Mid-drives are the Holy Grail power-providers for electric bikes. If you want to know how you can get the ultimate in efficiency and performance this is a good start. Mid-drives are not the cheapest electric bikes to build, but are the cream of the crop once you are out riding, especially off road, climbing hills or mountains. The mid-drive motor creates more torque for better hill climbing, it is centered on the bike for better balance, and it utilizes the gears for higher top end speeds and overall performance.
If you’re purchasing an ebike for rugged, off-road, hilly and/or technical terrain, then make sure you buy an ebike with a mid-drive motor. To better understand why a mid-drive motor is superior to a hub motor it’s important to elaborate on each.
A hub motor is typically placed on the rear wheel, although some front hub configurations exist. The hub motor is simple and quite inexpensive to manufacture and is therefore typically found on less expensive ebikes. Hub motors are heavy, cause uneven weight distribution, struggle climbing steep terrain, and have limited top end speed. Hub motors tend to be more about raw power and brute force whereas mid-drive motors tend to be more about smooth and efficient performance.
To better understand mid-drive motors please see below:
Performance:
Mid-drive motors are known for higher performance and torque when compared to a traditional hub motor allowing it to perform better on hills. One key reason is the mid-drive motor drives the crank, instead of the wheel itself, multiplying its power and allowing it to better take advantage of the bike’s existing gears. This translates to a happier more efficient motor and a lighter, better balanced e-bike. Why a lighter bike? When going through the gears, you don’t need as heavy of a motor to propel you up hills without smoking, and you don’t need as much battery because a mid-drive is considerably more efficient than a hub motor, especially when climbing. Mid-drive motors can leverage the lower gears of the bike and keep the rpm’s in an efficient range without getting “bogged down” like a hub motor. This is a good feature if you ride in areas that have consistently long and steep climbs. However, these motors can also leverage the higher gears of the drivetrain to cruise along at high speeds on flat or inclined roads.
Maintenance:
A mid-drive motor is designed to make maintenance and service extremely easy. The entire motor assembly can be removed and replaced by simply taking out a few special bolts – without affecting any other aspect of the bike. This means that virtually any regular bike shop can easily perform troubleshooting and repairs. On the other hand, if you have a rear-hub motor, even basic maintenance tasks such as taking off the wheel to change a flat tire become more complicated endeavors. Removing the front or rear wheel on a mid-drive ebike is easy because there are no motor wires or hardware to remove. The ebike with a mid-drive motor can also use most any front or rear wheel type along with quick release levers.
Handling:
Mid-drive motors are positioned at the center of the bike. This helps improve the overall handling of your electric bike by better distributing the weight, which contributes to better balance and thus a more classic bike feel. Mid-drive systems also allow for the use of cadence, speed and torque sensors. High-end mid-drive motors are pretty sophisticated with sensors that measure pedal power, wheel speed, and crank speed to provide assistance that blends with the riders’ power to create a very intuitive ride feel. A torque sensor is the best control you can have over an ebike. The harder you push the more assistance you get proportionally. There are also sensors that will reduce power when the system senses that the rider is going to shift gears to make the shift smoother. The Bakcou Mule and Storm models utilize Bafangs “high-end” Ultra mid-drive motor. The Ultra motor comes equipped with cadence, speed and torque sensors, as well as shifting sensors that reduce power in the motor when shifting to protect the gears and provide for smoother shifting. Please refer to the “Our Motor” page listed under the “Know Before You Buy” tab on our website for more information on this truly elite motor.
Limitation:
Other than price, the key limitation on mid-drive motors is that they are limited by the strength of the chain and the sprocket. Inevitably, a mid-drive will lead to increased maintenance on the drive train, including all cogs and sprockets. Thus, regular and routine maintenance is strongly encouraged and is extremely important.