The second part of the blog is titled “Be careful when buying an electric scooter! How long should CityCoco travel?"
In a previous blog post, we talked about the impact of the battery on the range. The battery is the most expensive part of an e-scooter. The second most expensive is the engine. Not only the maximum speed and traction of the electric scooter depends on it, but also the power reserve. A motor can waste energy inefficiently if it has low efficiency. The efficiency of low-quality Chinese electric motors can be 20-30% lower, respectively, the power reserve will be reduced by about the same amount. In this article, we will try to help you understand the electric motors installed in CityCoco electric bikes so that you avoid buying an electric scooter with a low-quality electric motor, as well as answer frequently asked questions:
- What types of electric motors are installed on CityCoco?
- The main problems of cheap engines, and how to avoid buying an electric scooter with such an engine?
- With which engine is better to choose an electric scooter?
In this blog you can also read about what resource the wheel motor has, what can disable it and how to properly operate it.
The electric motor has a parameter such as rated power. This is the power at which it works for an unlimited amount of time and does not heat up. Since CityCoco electric scooters are mostly unbranded, the Chinese hide the real power rating of the motors used. In order to save money, they put a weaker motor than it should be with the installed controller, and make it work at its limit. And on the cover of the electric motor they write max continuous power, or even peak power.
Max continuous power is the power at which the engine heats up, but not enough to burn out, and can work in this mode for a sufficiently long time, for example, an hour.
As a rule, this is the power consumed by an electric scooter when driving at maximum speed, provided that one passenger is traveling and there are no other loads in the form of additional. weight, flat tires, etc. Otherwise, in the presence of such factors, energy consumption will increase and the electric motor will begin to work for a long time already at peak power, which is unacceptable.
The peak power can be several times higher than the nominal, but at the same time, the electric motor can work under such a load without destruction for tens of seconds.
For a CityCoco electric motor with max continuous power of 1000W (the nominal can be 1.5-2 times less), it is usually equal to 1800W. Reaching peak power is needed so that at the right moment you can go up a steep mountain, accelerate sharply in an emergency, etc.
If you abuse the excess of the permissible load on the electric scooter, namely, create such conditions that the peak power will be supplied to the engine for minutes or even tens of minutes in a row, this can lead to a loss of properties of neodymium magnets, a drop in the efficiency of the electric motor and to burnout of the stator windings.
It's not a big problem if the Chinese indicate max continuous power instead of nominal. If you control the engine temperature under heavy loads, then it is quite possible to ride such an electric scooter.
Many different variants of engines are produced in China in a typical housing (no name brand). The most expensive part of an electric motor is the iron stator, which is paired with the windings as an electromagnet, as well as neodymium magnets. With an insufficient ratio of the amount of iron in the stator to the power of the motor, its efficiency decreases.
As an example, take the most common 8-inch engine available today.
In many cases, a stator and magnets with a thickness of 4 cm instead of 5 cm are installed on such a motor, indicating the power of 1000W (max continuous power).
Such a motor has a real rated power of about 500W, and when applied to it more than 1000W, the efficiency is greatly reduced. Inefficient use of power is spent on heating the windings and the likelihood of their burnout increases significantly.
In most cases, the "amount of iron" on branded engines can be found by the serial number on the rim itself. The thickness of the magnets corresponds to the thickness of the iron core, measured in millimeters and indicated by the letter H or C. Our electric scooters use branded motors with a wheel radius of 8 inches from the large Chinese manufacturer Weite Motor. This is how their serial numbers and internals look like:
The 8-inch motor-wheel, which is installed in the CityCoco electric scooter, must have a magnets thickness of 5 cm for a max continuous power of 1000-1500W, and 6 cm for a max continuous power of 2000W. The difference in the cost of a motor with a 5 and 6 cm stator can exceed $ 100, not counting the purchase of a more powerful controller.
The 2000W engine appeared in the second half of 2017. But this did not stop some unscrupulous sellers from selling a regular 1000W motor as 2000W, changing only one number on the motor case. In such cases, the Chinese almost always do not indicate the thickness of the magnets, perhaps because this deception is easy to detect when opening the engine.
This is how the serial numbers of such motors look, where the thickness of the magnets is not indicated:
Usually, such motors are characterised by a discrepancy between the power output and the amount of iron in the core, or problems with the quality of insulation and wire winding. And this is not counting the fact that the engine is constantly supplied not with the rated power, but with the max continuous power!
Attention! The power of the motor is also affected by the magnetization of the magnets themselves. We have described the characteristics of the motors taking into account the fact that when using a 5 cm stator, the weakest magnets with a magnetization index of 35 are most often used, therefore a motor with such a stator most likely has a max continuous power of 1000W. When using magnets with a magnetization index of 45, such a motor can have a max continuous power of about 1500W, but this is so rare in CityCoco electric bikes that you should not count on it. Accordingly, the real rated power of such motors (with a 5cm stator) is about 800W.
But to obtain a max continuous power of 2000W, a motor in such a case must have a 6-cm core and the most powerful neodymium magnets to ensure constant movement at speeds up to 60 km/h. If the magnets are weak, then the catch can be noticed - either the real maximum speed (according to GPS, and not the Chinese speedometer) will be below 50-55 km/h, or such an engine will get very hot when driving in a straight line or even burn out. The real rated power of such a motor is about 1200W, depending on the magnets it may be slightly higher, but you should not count on it.
It is almost impossible to check the magnetization, it is difficult to do even in comparison, therefore, the approximate engine power can be visually determined only by the amount of iron in the stator.
It is in no way possible to realize an engine with a max continuous power of more than 2000W at a voltage of 60V in an 8-inch wheel rim! There is simply no space in the wheel rim to install a thicker iron stator.
Be careful! At the end of 2020, CityCoco BR20 began selling an "updated version" with the declared 3000W, although in terms of speed and traction characteristics it is still the same 2000W.
Motor in 12" aluminum disc 1200-3000W
This 1200W engine appeared in 2016 at CityCoco Caigees and was successful due to the low profile of the tire, which gave it a presentable appearance. The use of this engine has increased the range and dynamics. On the other hand, road bumps are more felt on such wheels.
Various factories in China began to copy this engine and produce it in housings of different appearance, but the iron remained the same. A 10 "motor fits into a 12" disc, and the magnets and stator are 35mm thick. These dimensions correspond to a rated power of 1000w with a magnetization parameter of 35, or 1200-1500w at 40 (practically not found).
In addition to CityCoco Caigees, a similar engine is officially installed in the CityCoco Harley, which has been produced since 2017. For CityCoco Harley, the engine is made by one of the best Chinese brands QS MOTOR. Its rated power is 1200W, and it accelerates to a maximum of 43 km/h but still has high torque
It is a rarity to find such an engine on a CityCoco Harley, since in order to save money, a copy with the same internal filling is installed instead. We have CityCoco Harley electric scooters with original engines from QS MOTOR, but we use engines from other manufacturers on most scooters of this model, as the QS MOTOR factory refuses to produce these motors with winding at higher speeds for small orders.
Although the dimensions of this motor are rated at 1200-1500W (depending on the type of magnets), not branded manufacturers produce motors in this format to supply 2000W max continuous power, but 3000W peak and 3000W to achieve a higher speed. This type of wheel motor is able to withstand such loads, since the motor is installed in an aluminum disk and has an additional cooling area.
There are already many CityCoco on the market with a declared power of 3000W and a speed of 70 km/h. At the same time, peak power is indicated, and that is why these CityCoco simply cannot go real 70 km/h. The Chinese from the factory do not wind them at such a speed, since they cannot withstand 3000-3500W of max continuous power, which is necessary to be able to travel 70 km/h. The maximum that such scooters go is real 60-65 km/h by GPS. Sellers are trying to save the situation by selling a scooter with a speedometer lying in the big direction.
Since mid-2019, we have managed to modify the engine in a 12-inch rim for a max continuous power of 3000W. This is still the same motor with 35mm thick magnets, but the magnets are more powerful and more wire was used in the windings, with the "speed" winding type. Such an engine withstood driving on the highway for an hour at a speed of more than 70 km/h, which corresponds to a power consumption of about 3000W, therefore we declare this power on sale. The peak power supplied to this motor is up to 4800W.
When buying a CityCoco electric bike with a 12-inch rim and a declared power of 3000W, be sure to ask for a warranty on the engine for at least a year. After all, there are no overheating sensors from the factory, and these engines are the most overloaded, even during normal fast driving in a straight line.
13-inch aluminum rim engine with 3000W (From CityCoco LUQI)
2019 model, rated power 3000W. Autopsy of the motor showed a stator larger in size than installed in a 12 "motor, as well as a larger and thicker magnets - 4cm. Real rated power is about 2500W. Long-term power 4000W in our test calmly withstood. The motor is branded, made of high quality and has a fairly high Efficiency - almost 90% For correct operation and obtaining high efficiency it is used with the original Lingbo LBC006.551D controller. The peak current of the controller is only 45A, but in the case of the battery installed in the CityCoco LUQI with a capacity of 20 Ah, more is not needed.
QS MOTOR engine in 12'' aluminum rim with real rated power 3000W
For 2 years we tried to find an electric motor with a real nominal power of 3000W that could be installed on CityCoco, and finally in 2020 we succeeded. Why 3000W? Because in Ukraine you can drive without a license in a vehicle with a rated power not exceeding 3000W. But the max continuous power and peak power can be even more. Our goal was to find the highest quality and most efficient motor with such a power rating to deliver the highest possible max continuous power and peak power. With the correct rim diameter for CityCoco e-scooters, there are plenty of options in the Chinese market, including from the best company QS MOTOR, but they don't fit in width. Because the CityCoco form factor means wide wheels.
Since 2 years of searching did not bring any results, and the QS MOTOR company refused to produce the engine in a wider rim of such power, we had to order the manufacture of the disc separately, where the engine itself from this company was installed.
As a result, we got a wheel motor for CityCoco with a real rated power of 3000W, a max continuous power 6000W, and a peak power of 12000W. The aluminum disc, in which the motor itself is installed, provides additional cooling, we were able to supply 7000W of max continuous power and more than 20,000W of peak power to it. Peak phase current exceeds 400 amperes. What the CityCoco electric bike is now capable of, see the video:
Which engine to choose buying a CityCoco
To answer the question of which engine to choose an electric scooter with, we will try to describe the advantages and disadvantages of each engine.
1000W 8-inch wheel motor is an excellent choice for those who do not need high speed and will not be exposed to heavy loads. The controller is paired with such a motor as standard with a peak power of 1800W, and at heavy loads, the peak power can turn into constant. This is permissible for a motor with a max continuous power of 1500W, but not 1000W, for it it is several times higher than the nominal power. Quite often, such engines will burn if not properly operated. And rewinding the motor does NOT help, after a while it will burn out again, because the problem itself is not solved - you just need to reduce the peak power of the controller. To prevent this, starting in 2019, we install a controller with a peak power of 1300W for a 1000W engine, or we leave the standard controller with a peak power of 1800W, but put a temperature sensor in the engine, which will stop the electric scooter when the rated temperature is exceeded and turn it on after cooling down. We sell this configuration as 1500W.
The 2000W 8-inch wheel has significantly higher power headroom and is paired with a 2400W controller. Exceeding the rated power by less than 2 times. This is most likely why the 2000W engine burns less frequently. At the same time, the corresponding 2000W controllers for some customers, and for everyone who made additional sealing and blocked the ventilation openings, heated up so much that they melted all the wiring around, and eventually failed. But this is not a major problem, and we changed the controller under warranty. In order to exclude such cases, starting from 2019, we put a thermal sensor in the controller, which turns off its power when a high temperature is reached, and automatically turns it on after cooling.
2The 2000W 12-inch wheel is more efficient at low revs due to the longer lever, a sharper start up to 15 km/h, and less heat thanks to the large aluminum rim. Often found at CityCoco with a declared power of 3000W (not sold by us). The maximum speed is about 60 km/h, in rare cases 65 km/h.
3000W 12-inch wheel (found only in the CityCoco we sell) has a low efficiency at low rpm, due to winding at a high maximum speed, but taking into account the supply of a very high peak power (up to 4800W with a battery capacity of more than 60V 40Ah) an electric bike with such an engine has good acceleration dynamics over the entire rev range. Also, the maximum speed practically does not change from the presence of a headwind, or a second passenger. Since the peak power in this configuration is very high for it, it is not difficult to overheat such an engine with "ragged driving". But we install protection against overheating, and you will not spoil it, when a high temperature is reached, the engine will turn off for 10-15 minutes before cooling. In addition, it is not at all necessary to constantly twist the throttle handle all the way; good dynamics will be there even when accelerating to "half the throttle"
3000W 13-inch wheel has a high efficiency, and therefore economy, therefore it is an excellent solution for CityCoco LUQI, which has a battery capacity of only 20 Ah at 63V. But in terms of acceleration intensity, it lags behind our other electric bikes with 12 "3000W, due to the fact that the peak power supplied from the original controller is only about 2800-2900W. Also, the winding of the engine is not so high-speed, therefore 70 km/h can only be obtained in ideal conditions.In the presence of a slide, headwind, or a second passenger, the maximum speed will be noticeably reduced. This engine is found only on CityCoco LUQI. We practically do not use it in other models due to the complexity of installation on a different type of frame (wheel size is larger), etc.
3000W 12-inch rim motor from QS MOTOR has the best materials and build quality. The motor windings are completely varnished (which is practically not found in other types of motors installed in CityCoco), therefore, theoretically, it can be eternal, you just need to change the bearings.
So, if you buy CityCoco in our store, you can choose any type of engine with the characteristics that suit you. At the same time, you should not be afraid of any problems, since we additionally install overheating protection in all our models and by this we reduce the likelihood of an electric motor failure tenfold.
But if you buy/bought your moped elsewhere, then keep in mind that you definitely need to manually monitor the heating of the engine and controller, and follow the recommendations specified in this blog. Because no factory in China initially installs any temperature sensors for two reasons:
1) The main market where CityCoco is supplied is Europe, where no cases of controller and engine failure have yet been recorded. No one drives a threesome on flat tires, or rapes a scooter for hours in deep sand/mud. The European driving culture is significantly different from that in the CIS countries.
2) The installation of thermal sensors significantly increases the total assembly time of the scooter, and the Chinese are not only unprofitable, but they do not see the need, for the reason indicated in the first paragraph. And we are ready to undertake the installation only in case of ordering several thousand scooters. And do not forget that the more motors and controllers burn out, the more customers will buy new ones, and this is much more profitable for the Chinese than bothering with installing some sensors.
Since you most likely will not be able to determine the engine power when buying (for this you need to at least disassemble it, which most likely will not allow you), then look at least at the controller. By the link you can see which controller is paired with which motor, and the sizes of these controllers. Be especially careful when buying CityCoco electric scooters with 12-inch wheels with a declared power of 3000W, because all you can find in CityCoco market is just 3000W max continuous power, and real power is about 2000W.
If you have complaints about the weak torque of the electric motor, inadequate power reserve (provided that everything is ok with the battery), our service center can check your engine for the integrity of the windings and compliance with the declared power.