Rotary piston engine on a motorcycle

High specific power, compactness, manufacturability - these are the main advantages due to which the piston engine internal combustion(ICE) not only took a leading place among heat engines, but also successfully resists attempts to replace it with others power plants. Meanwhile, this engine also has serious organic shortcomings. One of the most significant is the reciprocating motion of the piston and the inertial forces generated by it, which cannot always be balanced. Hence - additional dynamic loads, vibrations, noise. Another is the presence in four-stroke engines a rather complex gas distribution mechanism that requires maintenance. That is why, in parallel with the improvement of traditional piston internal combustion engines, engineers and inventors have been working for decades on engine designs where the working body, the piston, would only perform rotational motion.

Among hundreds, and perhaps thousands of designs, only one was able to be brought to the level of requirement serial production. We are talking about the well-known rotary piston engine (RPE) by F. Wankel (Behind the Wheel, 1970, No. 12). Although the principle of its operation and design are described in the technical literature, let us briefly recall them.

Rice. 1. Diagram of the device (cross-section 4) and operation of the RPD: a, b, c, d - sequence of processes occurring at different rotor positions.

In the fixed housing 1 (Fig. 1) there is a triangular rotor 2. It rotates clockwise around its geometric center, which, in turn, rolls relative to the axis of the eccentric shaft b. When rotor 2 moves, each of its faces forms three working chambers of varying volume with the inner surface of the housing.

The edges of the rotor as it rotates describe an epitrochoid; The internal contour of the housing 1 is made along the same curve. The joint is sealed by the blades 15, placed in the slots of the rotor and constantly pressed against the working surface of the housing.

As the rotor rotates clockwise (Fig. 1, a), the volume of the upper right chamber increases, and the combustible mixture is sucked into it through the inlet window 17. The inlet into the chamber continues until the sealing blade reaches the right edge of window 17. Next, the volume of the chamber decreases and the mixture is compressed. When it becomes close to the minimum (Fig. 1, b), spark plug 7, in accordance with the selected ignition timing, will ignite the compressed charge of the mixture. The pressure of expanding gases on the edge of rotor 2 (Fig. 1, c) forces the eccentric shaft 6 to rotate. With further rotation of the shaft and rotor, the exhaust window 16 opens and exhaust gases are released (Fig. 1, d).

Thus, in each of the three chambers, the following occurs sequentially: the intake of fresh mixture, charge compression, ignition and expansion of combustion products, exhaust gas release, that is, the entire working process characteristic of a four-stroke internal combustion engine. For one rotation of the rotor, three working strokes are made.

The coordinated rotation of rotor 2 and shaft b is ensured by a pair of synchronizing gears 10 and 11, of which the smaller one (with external teeth) is fixedly mounted on the side cover of the housing. The gear, rigidly connected to the rotor, has internal teeth. Their ratio (2:3) is such that shaft b rotates faster than the rotor, and the working stroke occurs for each revolution of this shaft.

The main advantages of the RPD are its small size and weight, smooth operation, lack of a distribution mechanism, smaller than that of piston internal combustion engine, the number of parts - attracted the attention of leading engine manufacturers and car companies. The period of the 60s and early 70s was marked by intensive work on research and development of RPD in many countries.

NATI, a number of enterprises in the automotive and some other industries were involved in this problem. VNIImotoprom was one of the first to get involved in RPD work. Subsequently, the institute’s specialists were tasked with developing an engine for heavy-duty motorcycles (such as the Ural and Dnepr).

It must be said that both in design and in work process, and the RPD manufacturing technology has many features that radically distinguish it from traditional piston engine. When creating prototypes, we repeatedly had to solve problems that had no analogues in engine building practice. A number of materials and processes have been developed for the first time in domestic technology.

A set of studies that lasted several years led to the creation of a rotary piston engine, which received the index RD-515. Its bench and road tests on Dnepr motorcycles (see photo) showed good results.

Before talking about the possibilities and prospects for using RPD, let’s consider what the E1 engine, designed at VNIIMotoprom, is (Fig. 2). It is single-section. Its body, which has water cooling, form three parts 1, 8, 9 cast from aluminum alloy. Since inner surface The middle part of the stator 1 is working and must be wear-resistant and heat-resistant; a layer of nickel-silicon coating “Nikosil” is applied to it. It is more reliable than, for example, the well-known galvanic chrome plating. The technology of applying “nico-sila” to an aluminum base was developed for the first time in domestic practice by VNIImotoprom together with the Institute of Chemistry of the Academy of Sciences of the Lithuanian SSR.

To fig. 1 and 2: 1 — housing (stator); 2 - rotor; 3 — rear inlet window; 4 - cavity; 5 — roller bearing of the rotor; 6 — eccentric shaft; 7 - candle; 8 — back cover of the case; 9 — front housing cover; 10 - fixed synchronizing gear; 11 — synchronizing gear; 12 — front inlet window; 13 — inlet channel; 14 — carburetor; 15 - shoulder blade; 16 — end outlet window; 17 - end inlet window.

For reliable tightness of the housing joints and better heat transfer, the ends of the stator 1, as well as its covers 8, 9, are ground and connected without gaskets.

Rotor 2, which performs the functions of a piston, rotates (on the neck of the eccentric shaft 6) not on plain bearings, but on roller bearings 5. In its edges there are recesses that form combustion chambers. In the body of the eccentric shaft 6 there is a cavity for the passage of a flammable mixture, which simultaneously cools and lubricates (oil is added to the fuel in a ratio of 1: 100) two rotor bearings. They can withstand temperatures no higher than 250° C and therefore require intensive cooling and good lubrication. By the way, these bearings are among the parts that currently limit the life of the engine.

For a long time, the service life of RPDs was associated with the durability of the rotor seals, primarily at its edges. The problem was solved by selecting a special alloy. The seals themselves consist of blades and angles installed in grooves made in the rotor. Face seals are steel or cast iron strips. They are pressed by springy tapes made of a special heat-resistant alloy - expanders.

The design and working process of a rotary engine have features in comparison with a piston engine, which are reflected in the design of its main systems: power supply, ignition of lubricant, etc. In particular, they are of great importance both for obtaining the required power and for ensuring the required minimum content of toxic components in exhaust gases and efficiency has a design intake system.

The working mixture enters our engine in two flows - lateral and radial. The side one leads it from carburetor 14 to channel 13. There the flow is divided into two branches. Part of the mixture rushes into the working cavity of the stator 1 through window 12, the other - large - through the hollow eccentric of the shaft 6 into the cavity 4 of the rear cover 8 and window 3. The main flow cools the rotor and lubricates roller bearings.

The purpose of window 12 is to improve the filling of the combustion chamber working mixture and provide enough high power. For the same purpose, a radial channel was made (not shown in Fig. 2).

The ignition system is non-contact, thyristor with two spark plugs having a fairly high heat rating - 240-260 units. The need for two candles is due to the low height and long length combustion chambers, impeding the spread of the flame front and slowing down the combustion process. To start the engine, an electric starter and a kick starter are used.

The RD-515 engine is the result of many years of work, a comprehensive study of the features of the RPD, countless samples, inspections and tests. It is their results that allow us to consider the selected Constructive decisions optimal for an engine of a given size and purpose. We also built samples of RPDs with air-cooled housings. After comparative tests, preference was given to liquid system: such an engine is more reliable, durable and less noisy. Along with single-section engines, the institute also produced samples of two-section engines. We also tested motors with a tetrahedral rotor.

What does our rotary engine look like in comparison with its piston “brothers”? On his side - whole line benefits. Thus, the mass (and metal consumption) of the RPD is 13 kg (36%) less than that of a motorcycle engine of the same class, the overall volume is 2.5 times less, and the number of parts is one and a half times less. Operating fuel consumption is 10% lower than that of a motorcycle with standard piston engine. As for durability, the RD-515 covers 50 thousand kilometers without replacing main parts. This is quite acceptable for a motorcycle. The Institute, however, is working to further increase the service life of the RPD.

Having a working volume of one chamber of 491 cm3, RD-515 develops 38 liters. s./ 28.4 kW at 6000 rpm. Torque - 5.2 kgf*m / 51.0 N*m at 3500 rpm. The compression ratio is 8.7, requiring the use of AI-93 gasoline. Dry engine weight - 38 kg.

To date, in world practice, in terms of efficiency and toxicity, RPDs have practically been brought to the level of piston engines. But two equally important circumstances remain. First, the lack of technological continuity in the designs of the piston engine and the RPD is a very serious circumstance. Because of this, the production of RPD requires fundamentally new equipment and significant investment. The second is a certain distrust on the part of both specialists and consumers, based partly on the shortcomings early models serial RPD, partly due to poor awareness.

Nevertheless, the results achieved today in our country and abroad suggest that the 80s will be marked by a “second wave” of interest in RPD. The production of such engines seems justified in the conditions of our country, where heavy motorcycles, unlike Western countries, are very popular vehicle. At the same time, their production volume is still significantly less than passenger cars, and this would make it easier to develop the technology and solve other production problems at lower initial costs.

S. IVANITSKY, head of department
VNIIMotoprom, Candidate of Technical Sciences

The Merckx Motor Museum (Nuremberg) displays the world's first and only Hercules W-2000 equipped with a rotary engine. This amazing invention does not leave indifferent even the all-knowing cynics in the world of engine building.

In Germany, rotary engines are especially popular - the Germans love them for their funny running sound, high revs and for technological quirkiness. Such engines gained special respect after they were installed under the hood of many super-cool cars. These engines can also be seen in the frame of some motorcycles, such as the Suzuki RE5.

However, the motor installed on Japanese motorcycle- only a follower of the first, true innovator in the production of rotating ball motors. The first company to produce a miracle of technology was the German company Hercules. It was she who developed the first ever Wankel Rotary.

The Hercules company was created in 1886 by the famous businessman Karl Marshutz to produce bicycles. The price of a bicycle at that time was about 170 marks, and the demand for a new means of transportation increased every month. It was foolish to miss the opportunity, and the company produced 100 new bicycles in the first year of operation. Over ten years of continuous operation, the turnover of the company, which by that time had already become big company, reached 6,500 products per year.

In 1900, the company changed its name to Velocipedfabrik Marschütz & Co and began to actively develop the production of electric vehicles. Unfortunately (or fortunately) the production of electric vehicles quickly ended, but during this period the company set its own record - they released the first electric car that could travel 25 miles on a single charge, and it was a real four-wheeled car, with all its attributes modern car. Since 1904, Hercules turned all his attention to the development, production and modernization of motorcycles.

The first FN motorcycle was released in 1905. It is noteworthy that the engine for it was ordered and subsequently manufactured at a Belgian ammunition factory. This engine was turned on using a magnetic ignition system and had a carburetor that produced 4.5 hp. The transmission of revolutions to the wheels was carried out using a belt drive.

Continuing to develop, Hercules modernized motorcycle frames until the 30s and carefully hid all his engine developments from competitors. In particular, the company developed the Fichtel & Sachs system engine, which later became part of the ZF transmission.

The most famous engine of that time was the Saxonette engine, which was installed on mopeds. It had a power of 1.2 hp. and volume 60 cubic meters. cm. It was later integrated into the hub (manufactured by Torpedo) and installed in the body of the first Hercules motorcycle, the maximum speed of which reached 19 miles per hour.

Unfortunately, the company's founder, Marschutz, was forced to leave Germany in 1930 for California to avoid persecution because he was Jewish. The founder of Hercules was able to transfer only 25% of the shares of his company to America. His factory was nationalized and later completely destroyed during the war, the remains of production were looted, and the revival of the company began only in 1950. In fact, Hercules rose from the ashes and short time was able to satisfy the post-war German demand for motorcycles.

In 1960 the company was acquired by famous company for the production of Fichtel & Sachs engines. Under new management, by 1970 the company developed and released the E1 electric bicycle, which quickly gained popularity. Around the same time, a much more exciting example rolled off the Hercules production line. It was a W-2000 motorcycle with a Wankel engine.

Felix Wangel developed his first viable rotary engine in 1950. The license to use and implement the new technology was acquired by Sachs, which was the only company at that time that had the right to implement such developments. In 1970, the company's technologists, after five years of debate, decided to introduce a rotary machine into the Hercules line of motorcycles and showed for the first time new technology at the 1970 Fall West motorcycle display in Cologne.

New 294 cc engine cm produced 27 hp. power and cooled air system. For this purpose, the developers placed an axial fan in front, which could operate as a Idling, and on full speed. This design allowed to maintain the desired temperature in the engine.

In order to ensure proper lubrication of all rotating engine components, the racer had to pour oil directly into the gasoline. On later motorcycle models, starting with the “W-2000 Injection,” autonomous system lubricant, which consisted of an oil tank and an additional pump.

The first motorcycle had a single-rotor engine, which was secured under the frame with special bolts made of tubular steel. equipped with front disc brake, which could stop 18-inch wheels. The engine had a 90 degree rotation axis, which was connected to six-speed gearbox gears, it was also connected by a fuel line to a constant speed carburetor (Bing system).

At the end of the 80s, an experimental model of an escort (to escort convoys of official delegations and patrol service) motorcycle with RPD was created.
Specialists from the Izhevsk Motor Plant were entrusted with this project, and this was a full-fledged government order, which provided for the model to be put into small-scale production.
Bogatyrev Viktor Nikolaevich and Glukhov German Yakovlevich are working on the IZH-Lider model:

As power unit provided for the installation of a 2-section rotary piston engine RD-601. With a working volume of 613 cubic meters, it produced 52 hp. at 6000 rpm and maximum torque of 51Nm (at 3500 rpm). This installation was developed in Tolyatti and was largely unified with VAZ rotary units, which at that time had already begun to be actively installed on cars for special services.

The final version of the IZH-Lider motorcycle with RPD:

As a result of the design search, several running models of the “Soviet superbike” were born, which in their appearance resembled the best examples of the then Japanese and German motorcycles.

The first was the IZh Leader, a vehicle with a very developed hood and massive plastic fairings that well protected the driver from wind and precipitation. With its contours, it somehow reminds me of the legendary BMW K1 sports tourer, which was born around the same time (1988).

This is the condition the unique motorcycle was in the last time it was seen:


As on the Bavarian, engine thrust was transmitted to rear wheel by means of a cardan. Two experimental versions of the Leader were built: the first with the already mentioned RPD, and the second with the more familiar 2-cylinder opposed internal combustion engine from the serial Ural motorcycle.

And these are the remains of another Leader - with a motor from the Urals:

Another escort motorcycle from Izhmash it was named IZH-8.201 or “Vega”. He had a more graceful and swift appearance. Unlike the “Leader,” his appearance did not evoke associations with medieval knights.

In search of the optimal shape... The prototypes were built around both a chassis with a RPD and a conventional boxer engine.

The design practically corresponded to the best Western models, although some elements looked alien on such a handsome man: for example, the drums brake mechanisms or spoked wheel disks(although the project also included light alloys).

The final version of an escort motorcycle with a rotary piston engine:

Modern and attractive design:


Option with a classic internal combustion engine:


In addition to the rotary Vega, there was also a more down-to-earth version of this escort, in the chassis of which a 650 cc boxer engine from the Dnepr motorcycle was installed.

No worse than the then BMW, Honda and Moto Guzzi:


Reverse gear is cardan.


Drum brakes are not the topic here:

The creators’ plans were ambitious: to establish a full-fledged serial production such devices and even organize mass deliveries abroad - for the needs of police services in different countries.

A perfectly preserved example of IZH-8.201 at one of the modern exhibitions:


It's a pity that he never made it onto the production line.


2-section rotary piston engine RD-601 with a power of 52 hp:


However, perestroika, related problems in the USSR economy and the further collapse of the country put an end to these promising developments.


The power unit was built by AvtoVAZ specialists.


There are also spoked wheels.


The instrument panel is partially unified with the Zhiguli.

Interestingly, there were developments in the field of RPD in the Soviet Union. And if oh rotary car VAZ is known to many, its existence is in the past domestic motorcycles with engines built according to the Wankel design still remains a secret for many.

Back in 1970, road tests of the RD-350V engine, installed in a chassis from the Dnepr K-650, began. The dynamics of the car turned out to be satisfactory, the engine power was increased to 30.5 hp, but the very short life of the engine (only 100 hours) did not allow the development to see a bright future.

Created in 1972 new option RPD - RD-500V. Its body is made of aluminum alloy, with a chrome-plated working surface. The engine developed a power of 40 hp. at 6000 rpm. Road tests of the engine were carried out in the chassis of the Dnepr MT-9 motorcycle. They first tested a fuel injection system on it, but later abandoned it due to difficulty starting a cold engine (fuel injection systems of those times were far from perfect). The development of the RD-500V was the RD-501, created in 1973, in which a wear-resistant nickel-silver coating of the aluminum body was used, the engine rotor was made of sintered aluminum alloy, and the ignition of the fuel-air mixture was provided by electronic contactless system ignition

The decisive step was the transition to the system liquid cooling in 1976. This engine, designated RD-510, already developed 48 hp. at 6000 rpm. Further work was aimed at increasing the "survivability" of the engine, reducing fuel consumption and exhaust toxicity.

The single-section RD-515 was supposed to be installed on heavy motorcycles in the mid-70s. With a weight of 38 kg and a volume of 491 cm3. it produced 38 hp. (6000 rpm) and 51 Nm (3500 rpm). The end seals were made of steel or cast iron. Especially for this motor, they developed a technology for applying a wear-resistant, heat-resistant nickel-silicon coating “Nikosil” to an aluminum base. The unit was nursed until overhaul 50 thousand km.

The latest projects known to us in the field of domestic motorcycles with RPD are the RD-660 devices developed in the mid-80s and the RD-601 escort motorcycle (613 cc, power 52 hp at 6000 rpm)

It becomes clear that by the beginning of “perestroika” in the 90s, the institute had several proven RPD designs. But the further turn of events in our country killed all hopes for any successful continuation of development. Today, Soviet-era developments in the field of rotary piston engines can be observed in this state:

Found on the Internet.

Hello.

Throughout the history of the motorcycle, attempts have been made to mass produce motorcycles with Wankel engines, or rotary engines. Let's look at ten such motorcycles, according to Visordown.

The Wankel rotary engine, in terms of mass production, turned out to be one of the greatest technical failures of the 20th century. The designers promised us a revolution in the automotive and motorcycle industries, but over decades of work on the engine of this design they were unable to solve its inherent technical problems.

We will not delve into the details of the mind-blowing and seemingly not entirely logical concept of the operation of a rotary engine, but we note that the desire for motors of this design, in addition to power, is also caused by the lack of many parts, such as pistons, connecting rods, timing belts, etc. Unfortunately, this concept, as ingenious as it is mind-blowing, is squeezed into the framework of several design flaws, preventing it from winning over traditional piston engines.

We all know about the existence of Norton and Suzuki RE5 rotary motorcycles, but the history of motorcycle manufacturing also knows many other examples when motorcycles with such engines went beyond prototypes and entered the market. Here is our selection:

10: Hercules/DKW W-2000.

First on our list will be the oldest motorcycle with a Wankel engine. This is a Hercules, designated in the UK as the DKW W-2000. Record holder for sales among motorcycles with rotary engine, which issued 30 Horse power with an engine capacity of 294 cubic centimeters (although the volume of rotary engines cannot be compared with the volume of piston engines).

This motorcycle was produced in Germany from 1974 to 1977. 1800 copies were produced. As a drive to the wheel there is a universal joint, powered by a Bing carburetor.

9: Yamaha RZ201.

Don't worry, this is not a gap in your knowledge of motorcycle history. Yamaha never really launched mass production motorcycles with a rotary engine, but was already on the verge of this. In 1972, at the Tokio Motor Show it was shown Yamaha motorcycle RZ201 with a 660 cc Wankel engine producing 66 horses. Unfortunately, only a few prototypes were built, but if you really like this bike, you can turn your attention to the Yamaha TX750, with a traditional engine, but on the same frame and similar design.

8: Norton Interpol II

Norton worked on a prototype rotary motorcycle during the 70s of the last century, but such motorcycles did not go into production until 1984. However, the production was small-scale, it was something between a prototype and serial model, therefore, if the plastic seemed familiar to you, you were not mistaken - the entire body kit was taken from BMW motorcycle R100RT, the favorite motorcycle of the police in those years.

7: Kawasaki X99 RCE.

Let's go back to the prototypes again. The Kawasaki X99 RCE was a twin-rotor motorcycle with a 900 cc engine producing 85 horsepower, introduced to the public in 1972. But then Kawasaki realized the cost of production and licensing, and this motorcycle disappeared into history.

6: Norton Classic.

The result of endless design research was the production of the Norton Classic rotary motorcycle. Using the same twin-rotor 588 cc engine air cooling, as at Interpol II, a limited edition of 100 motorcycles was produced. This was the first attempt to produce a production rotary motorcycle in 11 years, since 1987, when motorcycle enthusiasts were able to see the Suzuki RE5.

5: Van Veen OCR1000.

One of the small Dutch motorcycle manufacturers has carried out an ambitious project to create a motorcycle with a Wankel engine. Twin rotor 996 cc (developed by NSU for Citroen cars) the engine produced 107 horses and could accelerate the motorcycle to maximum speed 135 miles per hour (217 km/h) is very healthy for 1978, in which mass production began, after several years of scientific research. The motorcycle had a nice appearance, although a rotary engine is initially not as aesthetically pleasing as a piston engine. Buyers, however, were not impressed, and during the years of production, from 1978 to 1981, only 38 units were sold. An attempt to revive production in 2011, at an indecent cost of a motorcycle of 81,000 Euros, added 10 more motorcycles to that result.

4: Norton Commander.

The Commander P53 was another production rotary motorcycle, released in 1989. It was based on a new twin-rotor water-cooled engine and was not too bad in any sense. Racing successes also helped give a small boost to sales.

3: Suzuki RE5.

In fact, if you want a rotary motorcycle experience, you'll almost certainly come to the Suzuki RE5. While competitors were limited to producing small batches, Suzuki was able to establish truly mass production of rotary motorcycles. You can still find a couple on ebay and buy them. The engine is single-rotor (less likely to have any problems), 65 horsepower, could not boast of power even in 1975, but the motorcycle has a neat design and distinctive style rear light and dashboard.

2: Norton F1.

Considering Norton's successful racing performances with Wankel engines, it seems strange decision install such a motor on the Commander, which was a tourer. But this oddity was eliminated in the 1990s with the release of the Norton F1, an almost full-fledged sportsbike, similar in design to the first generations of the CBR600, CBR1000 and Ducati Paso. About 130 motorcycles were produced.

1: Norton F1 Sport.

Finally a real sportsbike was released, earning itself a decent racing reputation at races such as the BSB and TT. Compared to the previous version, the side plastic was changed, now giving aesthetes a view of the elegant frame, and the shape of the saddle was changed. Unfortunately, at that time the Norton company was already in a state of agony, so it assembled the F1 Sport more for the sake of selling the remaining spare parts than for the sake of attracting consumers. In any case, the next rotary F2, although shown to the public in 1992, never entered the production line.