Do you know what is the most frequently asked question asked to us?
There is no unequivocal answer to this question, therefore, you will have to understand some of the nuances of the choice. By clicking on each of the pictures. you can get more specific information about each of the sets:
Therefore, in order to understand what components and how should be combined in your electrical kit, everyone must clearly define the following indicators for themselves:
2.What distance do you need to drive with electric traction without additional recharging??
3 how willing are you to weight your bike?
4.How much money are you willing to part with for re-equipment (the weight, type and durability of the battery and motor will depend on this)?
Top 10 Best E-Bike Conversion Kits
Speed - will depend on the power of the motor-wheel. Distance. from battery readings. Below. we’ll talk more about this.
Durability. on the cost, characteristics, compatibility, operating style and brand of the purchased equipment.
Well, now in more detail about the selection of each of the elements of the electrical kit. there are only 3 of them: motor controller battery.
Motor. can be a carriage (mounted in the carriage assembly of the frame, together with new connecting rods) and built into the wheel. the so-called motor-wheel.
The carriage motor is great. It. quite light, gives excellent weight distribution in the center of the frame, leaves native light, rolling wheels, but costs 2-3 times more motor-wheel and is located below the carriage, which frightens many. Therefore, 90% of cyclists refuse it at the very first stage of selection.
For those who simply need a speed of 60 km / h, they need a motor of 1000 W or more, 40-50 km / h. 500 W and 30-35 km / h. 350 W (or 250 W with operation when a voltage of 48 V is supplied to it). Let’s immediately state the weight of these motor-wheels in a condition that is lugged into the rim.
I note that the more its weight, the harder it spins up and the harder it is to ride it without using email. thrust.
Now. about the place of installation. for many. this question is very difficult and raises a lot of doubts. Our opinion is unambiguous: it is optimal to mount a 250-350W motor on the front wheel, in extreme cases. 500W. A heavy front wheel motor makes it difficult to control the bike and puts a serious load on the fork (it needs to be reinforced with a special fork amplifier in order to distribute the load from the wheel motor more evenly on the fork legs).
The rear motor. the wheel. creates a more correct weight distribution and better transmission of torque, since it is the leading.
BUT! Its installation is not as easy and painless as the front wheel hub motor, where you just need to rearrange your tires and tubes and adjust the brakes.
When installing the rear wheel motor, you need to take into account that instead of your cassette, you will need to install a ratchet cassette (or freewheel) on the wheel, which is screwed onto the corresponding thread on the motor. over, if the price of a ratchet for 1, 6.7 stars is about 300 hryvnia, then for 8 and 9 stars. about 800 hryvnia, and for 10 stars. it is simply not found anywhere
In addition, you need to be prepared that if you change your own (usually expensive transmission) to a simpler and more primitive one (since your drum-mounted cassette cannot be installed on a wheel motor), you will automatically have to replace rear derailleur, shifter and, of course. the chain.
Again, when installing a powerful motor on the rear wheel, you need to take care of unloading the dropouts to the maximum, which means it is advisable to install dropout amplifiers.
The durability of all equipment will directly depend on the correct selection of the controller.
Therefore. turning to professionals. you get a correctly technically balanced electrical kit.
Controllers can also radically (several times) differ in cost. It directly depends on the functions that it can perform.
So, a controller equipped with an LCD. display, having the functions of recuperation, assistance, brake levers with shutdown of the electric motor during braking. costs more than 4000 hryvnia. The simplest version of the controller costs less than 1000 UAH.
The battery parameters will depend on:
- How fast can you go
- How far can you travel on a single charge
- How many charge-discharge cycles will your battery last.
1) As I said, the speed depends on the power of the motor. But. not only it also depends on the voltage supplied to the motor. So, if a voltage of 36V is applied to a 250W motor (through the appropriate controller, of course), then it will go at a speed of 20-25 km / h, if 48V is applied, then the speed will already be 30-35 km / h.
Therefore. we pay attention to the battery voltage!
2) The distance that you can drive on a single charge directly depends on such an indicator as Ampere-hours. The more Ampere hours. the greater the distance.
So, for example, at 48V 5.3Ah, a 250W motor can drive 20-25km, and with a 48V 10.6Ah battery. up to 40km.
3) The durability or the number of charge-discharge cycles depends on the type of battery.
For relatively cheap (and the most difficult!) Lead-acid ones. it is 500-700 cycles, for lithium-ion. 1200-1500 cycles, for more modern lithium-ion Boston Swings. Boston Swing. up to 3000 cycles. That’s it. science does not stand still!
Below the video. there will be links to the most optimal electrical kits from our point of view:
- The lightest and most inexpensive electrical kit is a Boston Swing 48V and 5.3Ah battery with a 350W wheel motor. At the same time, the motor-wheel gives out a power of 350W (due to the fact that it is supplied with 48V instead of 36). It weighs only 5kg and allows you to travel 20-25km. developing speed up to 35 km / h. It can be mounted on almost any bike, and on the front wheel. absolutely no problem! Battery with controller. fits in your seat bag!
- The same electrical kit, but with a Boston Swing48V 10.6Ah battery. The distance increases to 40 km. Battery with controller. housed in a triangular bag in a frame triangle.
- powerful electrical kit with a 500W wheel motor. We recommend mounting it on the rear wheel. The Boston Swing 48V and 10.6Ah battery allows you to drive 40 km and accelerate to a speed of 40-50 km / h
We hope that our article has brought at least a little clarity when choosing equipment for an electric kit with which you will equip your bike in order to get exactly the kind of assistant you needed from the electric motor.
Remember: health and happiness are in your hands!
Varieties of motor wheels
The principle of operation of the motor-wheel turned out to be so successful that it is now used in all formats of electric transport and, by and large, has become the main one, displacing the chain transmission. Motor wheels are structurally divided into the following types:
- Gearboxes. Equipped with a special mechanism (reducer) and a clutch that allow you to freely adjust the speed. The main advantage of the design is that they allow the wheel to rotate even without traction. This type of drive is used with low-power gadgets that are used in relatively mild urban environments. The low weight of these MCUs makes them ideal for children’s e-bikes and scooters.
- Gearless. Such MCs do not have transmission mechanisms, in which the rotor and stator have a direct connection. Thanks to such a simplified design, these wheels are more reliable, have better traction and speed, and are able to work with heavy loads without problems for 5 years or more.
Also, when choosing an electric vehicle, you should pay attention to the location of the motor-wheel. It can be front or back. This aspect is especially relevant for bicycles, where the correct weight distribution is important due to the high center of gravity. When the MK is located in the front wheel, the rider will constantly feel uncomfortable due to the additional load on the hands (it is physically difficult to drive) and the decrease in the maneuverability of the iron horse. If a bike with a wheel electric motor in the rear, then you can only get pleasure from trips.
When deciding which wheel motor to choose, be sure to take into account the recommendations listed above, based on the advantages of the design.
How to choose a motor wheel for a bike
The choice of a motor-wheel depends by 99 percent on the conditions under which the operation will take place and what indicators the owner wants to achieve from the transport. The following are 3 typical choice situations:
- Need a low top speed, plans to ride around the city. In this case, a low-power gearbox type MK is suitable. 250 watts is enough. Such models are relatively lightweight (no heavy battery needed), easy to operate and inexpensive. If the rider wants to add speed (the need will be felt during acceleration), he can always help his device with his feet.
- A speed of 50 km / h is required, and the plans include driving not only in parks, but also on public roads and rough terrain. In this case, a gadget with an MK with a power of 1000 watts or more should be selected. You can opt for both geared and gearless versions. Definitely, the position of the wheel must be rearward. The weight of all electric lotions (MK, battery) of such a gadget will be 3-4 times more than that of the first option.
- The plans are to accelerate to 90-100 km / h, the funds allow you to purchase expensive vehicles. In this case, we choose from gearbox MK with a capacity of 3000 W and more. In fact, these are no longer bicycles, but electric motorcycle analogs, capable of traveling long distances and over any terrain. The weight of such a gadget will be appropriate. plus 30-40 kilograms will be added only by an MK with a battery.
You can rely on similar characteristics when selecting special kits, with the help of which a bicycle is turned from a purely mechanical into an electric one. It is important to keep in mind that powerful kits can only be installed on bicycles that have a sufficient margin of safety. MK with a power of 1500 W and above can be installed on mountain bikes or downhill models. Additionally, you will have to decide how to choose a controller for the wheel motor.
When deciding how to choose an electric wheel for a bicycle, it is necessary to assess the planned operating conditions of the gadget. The harder the future life of the iron horse is planned, the more powerful the wheel should be. For difficult conditions (rough terrain, ascents, high speed) gearless type MK is suitable.
Advantages of gear motors for freewheel wheel motors:
- light weight. less than 3 kg;
- small dimensions. slightly larger than a large rear wheel sprocket;
- low price in comparison with the direct drive motor;
- excellent bike roll with the engine off. If you run out of energy in the battery, you can continue to move as on a regular bike. The motor wheel does not slow down the rotation of the wheel;
- high efficiency of the engine. 30% in comparison with the direct drive engine. This means you can cover a third more distance than with a direct drive motor;
- high torque at low revs. Important for driving at low speeds on forest, country roads, overcoming steep climbs.
How to choose a wheel motor?
What type of wheel motor to choose?
Motors with a gearbox and freewheel and direct drive motors are used as electric motors in the wheel-motor set. All wheel motor motors are brushless brushless motors. Control of such motors is possible only with the help of a special controller of the switching stator winding of the motor according to signals from external controls. The controller is a mini computer programmed to solve the problem of controlling an electric motor using signals from external sensors and controls.
Disadvantages of overrunning gear motors:
- bike speed is not higher than 30 km / h;
- it is believed that geared motors have a slightly shorter resource due to the presence of a gearbox. However, it should be borne in mind that this type of engine is well mastered in mass production and is equipped with about 96% of all produced electric bicycles. Its reliability is extremely high, since the gearbox and freewheel are completely protected from dust and water ingress, and the gearbox itself is made of wear-resistant materials.
Disadvantages of direct drive motors for wheel motors:
- weight over 6 kg;
- large dimensions;
- high cost;
- 30% more battery power consumption compared to a geared motor;
The popularity of e-bikes is growing every day. There are many reasons for this:
- older people who are not able to make significant physical efforts to move on a regular bicycle acquire new opportunities to overcome significant distances with physical efforts that are feasible for them;
- summer residents, fishermen, mushroom pickers, can be happy to use these types of transport for long trips with a load on the trunk
- young people are not averse to driving a high-speed bike with friends and tinkering with converting their bike into a modern electric device.
Which battery to choose?
600C) allowing them to handle really well the harsh conditions of electric vehicles.
Which motor wheel to choose for a bike
Yake wheel motor is more beautiful, front and rear?
There are also a lot of articles on a qiu topic, I will write more free food.
In the first place, it’s not possible to unambiguously change the front and rear drive of the electric bike, but it’s not a bi-directional choice, only one option was sold, so that the motor should start to run for 1000. Mensh of the forced motors are used as front and rear, from the same to the skin from the options of their perevagi.
Well for perevagi in the front and rear motor-wheel? What are the hardened motors for the rear wheel drive?
Try the 1000 W motor-wheel and more immersion to fit the front fork of the bike. You can have a half-way dropout, as long as the motor-wheel doesn’t hang before the hour of a quick start, you can navigate from the start of the dropout. It is possible to break the fork itself back with a strong return of the important wheel with the motor, before the release into the hands of the cyclist himself and a shock absorber not to extinguish the impact of the seven kilogram motor. Through the straining motor itself, insert the leash into the rear wheel.
Motor-wheels with a medium force of 500 W can be used for both front and rear axles of a bicycle. Prior to the front-wheel drive, the following motors must be carried:
- Simplicity of installation for people who do not have to deal with service and repair of their bicycles.
- The shallowness of the electric bike has been reduced, especially on the high speed.
- The drive of the bike, as well as turning the pedals, additionally helps to collapse according to the squeak or the lack of traffic. You can’t find such a thing on motorcycles, in fact, a reversible bike is a new type of transport.
- An important steering wheel. If a 500 W wheel is directly driven, then more than 3.5 kg will be more important, which will become even more susceptible to bad roads, or to runt gravel. The output is seen, the hands are quickly tired, the comfort is meaningfully involved. For light motor-wheels, for example, a gearbox 350 W, the discomfort will significantly decrease, and the effect of the secondary drive will be unnecessary.
- Vigribannya ґruntu. a grip on the front wheel is indicated by the lower lower on the rear, as a result of the less expensive. It is possible to paddle the bike from the front wheel with a lot of weight without collapsing, to fly to the cyclist and on the flail, for such a quick soul, it is necessary to work, if you want to use the chain transmission.
The motor in the rear wheel is more suitable for electric bicycles. The balance of the weight of the bike is not noticeable and the balance of the weight of the bike is not noticeable. The installation of the rear motor-wheel is not very foldable, but if the electric kit is connected at once from the installation, then there will be no problems. It is required to denote a crumpled size:
- On the rear, the engine cannot accommodate more than 8 gears at once. For re-possession, it is better to go on off-road bicycles with good (not lodged) dropouts and 7-8 eyes on the rear hubs.
- Build up with accumulators, especially lead SLA AGM, on the trunk it is significant to ruin the corrugation of the rear-wheel drive electric bike, on the high speed of the rear you will wear it from side to side. Take the lead batteries and take the front lead.
For low-powered motors 350 W and at the bottom of the special growth there is no front drive and rear drive, and for an easy trip in the middle of a short walk, there is absolutely enough pressure.
Which wheel motor is better, direct drive or geared?
We are very often asked which motor-wheel is better, geared or direct drive. We will not give a definite answer, since each of these two types of motor has its own advantages and disadvantages. For some, one thing will seem important, for someone else.
To save you time. let’s write a short excerpt:
- If you need a speed higher than 30 km / h, then you need a direct drive wheel motor with a power of 500 W or more, but at the same time be prepared for the fact that the turned off motor will offer little resistance when driving, and if you want a confident climb up the hill. then the power must be 1500 W or more.
- If you are satisfied with a speed of up to 30 km / h, then a gear motor-wheel of 350 W is suitable for you, while you will get a confident climb uphill, no resistance when driving with the engine off, as well as low weight and dimensions of the motor. If this suits you, then the disadvantages of the gear motor are already insignificant.
- Both wheel motors are brushless.
Wire-Spoked Wheels vs. Alloy Wheels—Which Are Better? | MC Garage
Gear motor-wheel 250-350 W.
To begin with, we will briefly tell you what a gearbox is and why it is installed in an electric bike motor. Reducer. it is a device that increases the torque of the motor-wheel, but at the same time reduces the maximum travel speed to 30 km / h. That is, it will be easy to drive up the hill, but on a straight road the speed will be low. This is the same as driving a car in first or second gear. Direct drive wheel motors will have the same torque available at 1500 W.
The gearbox consists of a planetary gear set with three plastic gears inside. The service life of these gears depends on the operating mode and averages 6-9 thousand km. Replacement of gears. it is not difficult, it takes 1-2 hours, and their cost can be found here. There are modifications with steel gears, but this is rare since these motors are quite noisy.
Gear wheel motors have no resistance when driving with the motor off. In other words, if your battery runs out, you can ride like a regular bike. Good roll is provided by the overrunning clutch, which mechanically disconnects the motor from the wheel; it can be compared to a ratchet on the rear wheel of a bicycle. when you need to, you start pedaling and transmitting torque to the wheel, but the wheel cannot transmit its torque back to the pedals. The flip side of this advantage. the impossibility of recuperation, that is, you cannot brake the engine and charge the batteries.
The next distinguishing feature of the geared wheel motor. it is compact and lightweight. Many will not even suspect that you have an e-bike, since the motor in the wheel will be slightly larger in diameter than the hub. This is again due to the presence of a gearbox inside.
Most geared motor wheels have a maximum power of 350 watts, a little less than 500 watts, but no more. This is a relatively negative side of this type of wheel motor, since not everyone needs more powerful motors.
It is also worth noting the low noise level of the geared motor-wheels, they are practically silent. Not to say that the direct drive is noisy, but still it works a little louder than the geared motor-wheel.
And finally, about the price. Gear motor-wheel is cheaper than motor-wheel with direct drive.
Direct drive wheel motor (gearless).
This design has two main parts. rotor and stator. Rotor. this is the axle of the wheel with windings, it is stationary and rigidly fixed to the bicycle frame. Stator. This is a wheel hub with powerful permanent magnets, to which the spokes and rim are fixed, it is movable. This design is extremely reliable and simple, since there are no rubbing parts in it, except for the bearings. This is a classic three-phase AC motor circuit, only in it the stator rotates around the rotor.
- Reliability and simplicity of design
- Ability to brake by the engine (recuperation)
- High power up to 5000 W
- Travel speed up to 100 km / h
- Higher efficiency due to the absence of a gearbox
- Slight resistance when driving with the engine off. That is, if you run out of battery, then pedaling will be a little harder than on the same bike without a motor. This resistance is comparable to a light head wind.
- Large dimensions and weight of the motor
- A motor-wheel with a direct drive is more expensive than a gear motor with the same power.
Bottom line: if you need a good speed from 30 km / h. choose direct drive. In other cases, it is worth giving preference to a geared motor-wheel.
Its power ranges from 250 to 350 W.
The key features of this device are as follows:
- The reducer is designed to increase the torque, which causes a decrease in travel speed to about 30 km / h. However, due to this, climbing the mountain is greatly simplified, less effort is required. Achieving a similar torque with direct drive is possible only with an increase in power to 1500 W.
- The design of the gearbox is represented by a combination of several gears. The service life of moving elements largely depends on the mode of operation and correct maintenance.
- Gears cause noise or hum during operation. In addition, due to the resulting friction, the structure can become very hot.
- The main distinguishing features are relatively light weight and compactness. Modern technologies make it possible to make a device, the diameter of which is greater than the diameter of the sleeve.
- The negative side is that the maximum power is about 500 watts.
In order to be able to ride upwind, when choosing, you should give preference to electric bicycles. In addition, the installed electric motor allows you to travel a long distance at a high speed with less cost.
The wheel motor was invented almost simultaneously with the electric motor. It is characterized by its own characteristics, which we will talk about in more detail below.
How to choose a wheel motor for a bike. tips
The main characteristics of the wheel motor determine the selection recommendations.
They look like this:
- Achieving speeds in excess of 30 km / h requires a direct drive mechanism with a power of 500 watts or more. However, when installing it, it should be borne in mind that it will be much more difficult to pedal with the engine off.
- If a speed of about 30 km / h is sufficient, then you can give preference to a motor-wheel with a gearbox, the power of which is 350 watts. Due to this mechanism, conditions are provided for a confident ascent uphill, and when driving with the engine off, additional resistance will not be created. Also, the mechanism is small in size and weight.
Motor-wheel for a bicycle. description
The key feature of the wheel motor is that the wheel axle acts as the stator axis of the electric motor. The emergence of modern injection molded batteries has become an impetus for the development of this area, since they can withstand a large number of recharge cycles.
The main operational characteristics determine the use of the wheel motor in the creation of bicycles and mopeds, as well as other light vehicles. At the same time, the device has its advantages and disadvantages.
Direct drive wheel motor
A direct drive wheel motor is characterized by two main elements: stator and rotor.
Let us call their features the following:
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- The rotor is represented by a winding wheel axle. It attaches to the bike frame.
- The stator resembles bushings with a powerful permanent magnet. The spokes and the rim are attached to it, during movement it rotates around the axis.
- The design in question is quite simple and reliable, since there are no rubbing elements.
- The advantage is that the power can reach 5000 watts. In addition, the maximum travel speed is 100 km / h.
- The efficiency indicator is much higher when compared with a gearbox.
However, the direct drive mechanism has several significant disadvantages, for example, friction occurs at the moment of movement. Therefore, pedaling will become much harder. In addition, to achieve the required power level, a device with large dimensions is needed.
Principle of operation
A common motor-wheel is practically no different from a brushless synchronous motor.
Its features are as follows:
- A rotating magnetic field, which is a moving force, is created by the motor by switching the winding with a special key by the controller.
- The switching frequency also depends on the speed of rotation of the wheel.
- When creating a structure, a fairly large number of permanent magnets are used.
- The design has no brushes and other rubbing elements, except for the bearing on the axle. Due to this, the efficiency rate is increased up to 90% and the degree of wear of the structure is reduced.
Advantages and disadvantages
The wheel motor is characterized by certain advantages and disadvantages that must be taken into account. In this case, it is worth considering the variety of this element.
The main advantages are the following:
- High efficiency factor. The above information indicates that the efficiency is at least 90%. This value is not typical of many electric motors.
- The design is characterized by simplicity and reliability. The absence of wear parts determines a long service life.
- The device is capable of providing a high speed of movement of transport. Common versions with a power of 500 watts are capable of speeds of about 45 km / h.
There are also several significant disadvantages. They are as follows:
- Low torque. Other types of electric motor have a higher torque rating.
- Quite large in size. This does not allow the use of a wheel motor when creating compact and efficient designs.
- Great weight. When compared with other motors, the considered one has significant weight.
Types of motor wheels
There are two different motor-wheels that can be used to create bicycles and other vehicles.
Ordinary motorized or geared?
It does not matter if the electric motor is connected via a chain drive (drives in the carriage) or not (front, rear motor, friction gears), the bicycle speed system will still be involved.
The gear motor wheel allows you to move using a reduced gear ratio. It can help a cyclist to climb a very steep hill when using a motor with a highly reduction planetary gear. In this case, the engine will operate close to the highest efficiency point, as it will maintain high rpm. But still, there will be a loss of efficiency in a motor with a gearbox, since such systems are complex and some frictional waste is inevitable in them.
Gearless systems do not decelerate the engine. Consequently, the efficiency of the engine in them is not constant, but very often depends on the speed of the bike. But such systems are simple, so their total efficiency is higher compared to geared motors.
As you can see, there is a problem of choosing between electric motors with and without a gearbox. On the one hand, the former can maintain the same engine efficiency over a wide range of speeds, while the latter have inevitable losses when the speed decreases. On the other hand, electric motors without a gearbox have a high overall efficiency.
When trying to climb a very steep slope or when carrying heavy loads, your average speed drops quite a lot. In this case, a motor without a gearbox will operate at a level with a significantly reduced efficiency. For uphill climbing, the gear wheel will be the best choice.
However, it is safe to say that in other riding conditions, a motor without an undershift will do its job better (especially on frequent long trips) than overly complex systems with a gearbox.
Electric motors specialization
The electric bike wheel motor can be specially designed for better uphill climbing or optimized for increased range or increased travel speed. High horsepower engines have a high hill climbing ability (torque), but they reduce the travel range (quickly drain the battery).
The efficiency (efficiency) of the engine in terms of power is not constant, it has a maximum value at a certain speed. Also, its value depends on whether the speed increases or decreases.
After each ascent, there is a descent from the hill. it’s just like the cycle of substances in nature. Downhill, with regenerative braking, the electric motor can charge the battery and extend the range of the e-bike. Electric motor designed by V.V. Shkondina can, when generating, return the maximum part of the energy that was spent on climbing the mountain.
Generating energy slows the bike down, so installing a Shkondin motor would be a good idea if you want to limit the bike’s top speed downhill, naturally without using the brakes.
In addition to regenerative resistance, each electric motor has internal friction, so any drive on an electric bike will somewhat reduce the top speed when coasting compared to a conventional bike.
Analysis of different electrical kits
There are two possible options for electric bike kits:
- A motor installed in a wheel. This system does not take advantage of the bicycle gear system.
- A motor inserted in a carriage (such as the Optibike MBB system) that can be rotated in parallel with your feet. This system is activated through the bike’s chain drive.
In the first case, the chain transmission system remains unused, and you can not rely on the maximum efficiency of the engine when going uphill. In the second case, of course, you will lose a little on friction in the chain drive, but you will be able to optimize the efficiency of the engine when changing the speed.
When changing gear, torque is always lost. Therefore, it is advisable to always start uphill in the appropriate gear or make as few changes as possible when climbing.
Even a geared motor is affected by gear changes. After the rider changes gear, any engine will have to change the speed. In this case, it will be better if the cyclist gives extra push through the pedals after the gear change. The front motor wheel also loses torque along with the rider when changing speed, as they are combined into the same gear system.
What is a bicycle wheel motor and how to choose it
Many people choose to use e-bikes because they help to ride against headwinds and climb high hills. Everyone can now assemble an electric bike with their own hands, thanks to the many sets brought from China.
But the electric bicycle only increases the strength of a person, and does not completely replace it. Thus, pedaling while riding an e-bike is still required, and especially when driving up a slope.
Unlike other motorized vehicles, which only have a motor to push the car forward, an electric bicycle combines the power of a motor with the power of the rider. Machines that combine power from different sources (for example, a motor and a person) are called hybrid.
When a person is not sure that a specific set with an electric motor will help climb to the top of a hill, he is lost in thought: what if the hill will be even steeper or longer. And naturally everyone wants the most powerful electric bike kit ever. However, in many cases the most powerful electric motor will be overkill, and you will end up spending too much money and carrying around much more weight than you really need.
You can climb a low hill with almost any motor-wheel for a bicycle. And if at the same time lightly pedal, then you can easily climb a steep hill, even under difficult conditions. strong headwind and heavy rider weight. Compared to conventional bicycles, electric bikes will pleasantly surprise you.
Examples from real life situations
Take, for the first example, a standard motor with a maximum power of 250 watts at 10 km / h and a cyclist who can also bring in 250 watts (not trying hard) to maintain a given speed. Together they deliver one impressive 500W of power.
- At a speed of 10 km / h, a rider can climb a hill with a slope of 17.5% with 500 watts of combined power.
- At a speed of 8 km / h, a cyclist can climb a hill with a 17.5% incline with his 250W and a motor running at 80% at 200W.
- At a speed of 6 km / h, a cyclist can climb a hill with the same incline of 17.5% with his 250W and 125W motor running at 60%.
At first glance, these results may seem completely inaccurate, because only the efficiency of the electric motor goes down along with the speed, and it seems that the cyclist can still climb the same steep slope.
This inaccuracy will be resolved when we understand how important a person is to the operation of an e-bike. Let’s see what would happen if the cyclist did not press the pedals at all and all 500 watts (as in the example above) came from the motor.
- At 10 km / h, a cyclist would only be able to climb a 17.5% incline with the 500 W engine running at 100%.
- At a speed of 8 km / h, a rider can climb a hill with a lower incline of 17% with a 400 W motor running at 80%.
- At a speed of 6 km / h, the rider can drive up a hill with a slope of 14.5% with only 50% of the 250 W motor.
These results are taken from the e-bike calculator with the following inputs: total weight. 100 kg; frontal resistance area. 0.4 square meters; friction coefficient. 0.7; lifting length. 100 m; headwind speed. 10 km / h and rolling resistance coefficient. 0.007.
Race around the city on a self-assembled electric bike with a motor wheel:
Rider strength is most important when you need to maintain speed on an e-bike, because when it drops, engine efficiency is greatly reduced. By analyzing this, you will be able to understand how an e-bike is different from any other motorized transport and why installing geared motors is not always the best choice. It is better not to put a motor with a gearbox in the front wheel at all, because it should have a free roll.