Types of electric bicycle drives. Electric bicycles with all-wheel drive (2WD) Rear-wheel drive hybrid bicycle

All-wheel drive vehicles have long proven their advantages. They can easily cope with off-road conditions, and in difficult conditions on ordinary roads they behave more confidently than other vehicles. Unlike cars, four-wheel drive bicycles are much less common. Until recently, they were considered a curiosity. The creation of single models with two-wheel drive was carried out mainly by amateur experimenters, and even then quite rarely. The Japanese company Arte Co Ltd has undertaken to break the tradition. It mass-produces several models of the Tretta AWD bicycle, which has both wheels driven.

Tretta AWD bikes have been available to buyers in Japan for almost a year now, but made their world premiere last fall at the 2012 Interbike trade show in Las Vegas.

The layout of an all-wheel drive bike is similar to a regular rear-wheel drive bike. The force from the pedals is transmitted through two sprockets and the chain to the rear wheel axle. The chain is, as usual, on the right side. On the other side of the wheel, an additional sprocket is installed on the rear axle. With its help, the force of the cyclist's muscles is transferred to the front wheel. For this, three more chains and two intermediate axles with two sprockets each are used, not counting the front wheel axle. The axle connecting the top sprockets of the frame and the steering fork is articulated, allowing the front wheel to turn.

The idea of ​​the designers was to increase the cross-country ability and stability of the bicycle in difficult conditions, on wet or snowy roads. It is difficult to judge how successful they were, but today there are mountain, cross-country, beach and city models with all-wheel drive on sale in Japan. Their prices range from approximately 33 to 75 thousand yen (from 400 to 900 dollars).

Everything would be fine, but all these sprockets and chains seem to significantly weigh down the bike and do not add to its reliability. As you know, the most capricious part of any bicycle, requiring constant attention and care, is the chain. There are four of them in the design, which means you will have to lubricate and adjust the mechanical transmission four times more often than when using a regular bicycle.

Surely many people know how a chain can “chew” trousers. As you can see from the photos, when driving a Tretta AWD, even rolling up your trouser leg won’t save you from trouble; the chain is located too high, and if it can’t “chew” your clothes, it will probably get dirty.

The company is aware of this shortcoming and assures that in the next modifications of the all-wheel drive bicycle they will try to get rid of it. Maybe they will replace the circuits with electrical wires?

An electric bicycle, also known as a hybrid bicycle, is a bicycle that is partially or fully powered by an electric drive. Let's leave aside the necessity or uselessness of this type of transport, we will definitely discuss this later, but let's figure out what the electric bike is made of and what it comes with. First, let's talk about the types of motor drives and their features.

Let's start with the fact that all types of motors can be divided into only two classes:
– Motor-wheel
– Carriage motor

But I will divide it according to the “classical” scheme - by type of drive:
– Rear
– Front
- Full

Let me clarify right away that everything is compared in the format, all other things being equal: power, voltage, . And you can always find out the current prices for electric bicycles and hybrid bicycles on Eko-Bike.ru - the website of the No. 1 electric hypermarket in Russia!

Rear-wheel drive bicycle hybrid

Motor-wheel. The easiest motor to install, simple in that any frame is suitable for a low-power motor (up to 500 W). The weight distribution of the bike is with emphasis on the rear wheel. When starting, the bike always tends to get a little stiff, and if the start is made on moving ground, the rear end will start to move. You should also be careful on slippery and loose soils when turning, the rear will skid. This type of drive handles slides well, but I wouldn’t recommend it for older people. One of the most popular electric bicycle drives in the world at the moment.

Carriage motor

In essence, it is rear-wheel drive, but with one significant caveat: this is the only type of motor that requires rotation of the pedals (perhaps there are already motors that have free wheeling, but the author is not aware of such). Technically, the motor provides the least torsional resistance, so it is easiest to pedal with such a motor. Essentially it gives you all the benefits of a regular bike and just helps you pedal. Often on such motors there is no throttle handle, and the motor is connected to Pedal Assist and turns on only when the rider starts pedaling. If you look at the market as a whole, then the “top” manufacturers of conventional bicycles have models of top-end electric bicycles (flagships) and almost all of these models have a carriage motor. In fact, this is the best and most visual integration of a bicycle and a motor, a true bicycle hybrid.

Front-wheel drive electric bicycles

Motor-wheel. A more complex motor, which requires the installation of amplification of the dropouts to compensate for the reactive torque, it is recommended to amplify them with a power of more than 250 W. With this arrangement, the weight distribution of the bicycle is more correct and it is much easier to carry. The start is always very smooth, which makes it more convenient for older people, but otherwise there are more disadvantages. When starting hard, the wheel is guaranteed to spin before the bike starts moving. The same thing will happen when going uphill. The steeper the hill, the less grip there will be, even if you lay down on the steering wheel. Although, there will be no skidding in corners, so this is also worth writing down as a plus.

Electric bicycle with all-wheel drive

Two motor wheels. Consists of a combination of the above drives. It has both its pros and cons. The advantages include the weight distribution of the bike, as well as complete control both when going uphill and cornering. From the point of view of cross-country ability and controllability, this type of drive has absorbed all the best from the previous two, but there are also disadvantages. The first and most important thing is that the synchronization of the motors is carried out entirely through the controller and desynchronization can lead to the combustion of the motor or motors. Another disadvantage is the weight, which will be the greatest among all options. And finally: all-wheel drive is the most voracious, so you have to pay for cross-country ability with driving range.

Here you need to understand that in the case of a wheel motor, everything depends on the power and voltage of the motor. Of course, 250 W will not stiffen the bike in any way or spin the wheel at start, but with increasing power and voltage, the above-described nuances will be felt more and more strongly.

This is the first article that will open the way for our project into the world of electric bicycles. I hope you enjoy the material. For consultation on this issue, the author thanks the Eltreco company, which allowed us to test electric bicycles and check everything in practice.

Thank you for attention,
Alexey Evdokimov

Everyone is already tired of topics about all-wheel drive SUVs or cars. We are for electric transport – electric bicycles.

Today we will talk about all-wheel drive on electric bicycles!

Do you live where the roads are snowy, or where there is a lot of rainfall and you have to drive on sand or mud. You would like to get more grip, and therefore more traction and driving confidence, your solution is two-wheel drive 2WD.

Previously topics all-wheel drive e-bike have already been raised, there were also proposals to make very wide tires on bicycles. However, to be completely sure, we see that in cold weather conditions the installation of a second drive wheel is a necessity.

Alas, but now I have not come across serial 2WD electric bicycles, and of the usual ones, to be honest, the factory versions are very sluggish, and those that are faster are very expensive.

Two-wheel drive

The first bike I came across online was made by Zlatko from Croatia. He loved motorcycle racing and decided to create his own all-wheel drive e-bike. It sits at the bottom of the frame, and he used two small ones that look like drum brakes on motorbikes.

Despite the low power of the electric motors, the entire structure turned out to be quite powerful, because two motors worked in tandem. This solution doubles traction due to the large contact patch between the tire and the road surface. If you take one motor that is equal to the total power of two, it can easily cause the drive wheel to slip. This is dangerous not only on bad surfaces, but also on good ones. You can fall off your bike. This also has a negative impact on acceleration.

The next example of a 2WD e-bike found was built by electrical engineer Allan. A distinctive feature of this bicycle is its long tail (cargobike) and he called it Teklektik. The batteries are located on the sides near the rear wheel on special stands.

For construction, the Yuba Mondo set was taken as a basis and each element was carefully examined. He decided to use two mid-size geared wheel motors, which were more than enough for a confident ride.

The next no less interesting example of an electric bicycle with all-wheel drive was designed by Ben from Taiwan. He had long wanted to make a full-size e-bike so that he could take it on the train for day trips to the beautiful places in the mountains of Taiwan.

The owner of this bike lives in an area where the roads are quite steep and the surface is uneven, which gave impetus to the development of this project. Ben had used an e-bike before, but only with single-wheel drive, which meant that the tire had to be changed frequently and the traction left much to be desired.

When designing this e-bike, he decided to abandon the idea of ​​two identical controllers and chose a dual MAC controller for the wheel motors. The motor wheels were chosen to be the largest gear type. Each uses a 22mm wide stator.

The owner of the next electric bike wanted to ride it for a distance of 1600 km. (1000 miles) and decided that all-wheel drive would not hurt him. This is what happened.

Based on the above examples, we see that two medium-sized engines can provide the same power as one large engine, which is an undeniable plus. The disadvantage of this solution is the use of high-capacity batteries because... Two motors are being powered.

Electric bike 2WD 8000W (power!)

Photo

What is needed to successfully navigate Antarctica so that it looks like a crazy adventure, and not just another whim of the rich? The all-terrain vehicle disappears immediately, the snowmobile and snowmobile in the Moscow region (sit there and burn gasoline), you feel sorry for the dogs, besides, they periodically get tired and ask for food, you can’t go far on your own two feet, and now there is only one option left - a bicycle!

You may ask: what respectable bicycle of a sober mind and bright memory can ride you across lifeless icy deserts covered with millions of tons of snow? We have one in mind!

Everything is like other mountain bikes, except for one thing: it is all-wheel drive.

The AWD bike, made by the Christini brand, like any of its other brothers, has only 2 wheels (albeit very thick ones), a fork with shock absorbers, pedals that rotate the chain, a couple of dozen speeds, a handlebar and a saddle - in a word, everything is like other mountain bikes. bicycles. Except for one thing: it's all-wheel drive. Yes, everyone has long been accustomed to the “4x4” icon, but “2x2” is most often perceived as the logo of a famous TV channel. The idea of ​​an all-wheel drive bicycle appeared quite a long time ago, and it was brought to life and patented by Steve Christini, who put his first creation on sale back in 2001. Today, he actively uses his technology in the production of all-wheel drive motorcycles.

Why this is needed at all is clear, first of all, to those who see the difference between all-wheel drive and part-wheel drive in cars in off-road conditions, or to those who have ridden a regular bicycle in snow or sand. With the usual expenditure of effort on an all-wheel drive bike, you get excellent traction, and the front wheel is not just matched by the rear and acts as a steering wheel, but also takes a direct part in the movement.

The so-called fatbike was taken as the basis for the ice desert tamer.

The AWD technology itself is a mechanism of simple, but very advanced gears hidden in the frame and fork. They transmit torque from the rear hub to the front. The result is an all-wheel drive bike that can effortlessly make its way through sand and snow. Actually, it is for the sake of the latter that the model we are interested in was developed. The Christini ice desert tamer was based on the so-called “fatbike”, which has taken root well in the MTB world even with one drive wheel. Of course, the bike is not fat at all, it’s just that its front fork and rear triangle are designed specifically for huge 29-inch wheels, which significantly reduces the pressure of the bike on the snow surface and prevents it from digging deep.

Mr. Christini developed his all-terrain vehicle specifically for one restless athlete from Australia, who decided to conquer Antarctica with it. Initially, a regular fat bike was considered as a workhorse. But having covered several thousand kilometers around the globe, Kate Leeming decided that cycling around the South Pole needed something more serious. The bike has already been tested in conditions as close as possible to Antarctica - in Spitsbergen. You can find out what came of it from the video.