"Handsome" - so called the Soviet daredevils and connoisseurs of motorcycle technology model "K-175", which became fundamentally new and technically perfect back in 1957. The prototype of the famous Kovrov iron horses served as a trophy model of German motorcycles "DKW-RT-125". It was the best of the lightweight motorcycles with a displacement of 125 cc from the 1930s-1940s.

On the history of the development of motorcycle models "Kovrovets"

A year after World War II, in 1946, the first models of Kovrov motorcycles with a working volume of 125 "cubes" were produced. The model was called “K-125”. This motorcycle was actually a complete copy of the German "RT-125", which in the first year of production, 286 units rolled off the "Degtyarev" conveyors.

Motorcycle "Kovrovets" 125th model was one of the best Soviet light motorcycles, which were produced up to 1951. Then the technique was modernized, which consisted in improving comfort and convenience while driving. In the period from 1951 to 1955, Kovrov craftsmen produced the K-125M model.

In 1955, the management of ZiD (Kovrovsky Plant named after Degtyarev) decided to release fundamentally new motorcycle models, which were supposed to differ from their predecessors with improved performance characteristics. This is how the K-55 model appeared. This motorcycle "Kovrovets" was equipped with a completely new type of carburetor and a modernized exhaust gas removal system, due to which it was possible to increase its power.

The turning point 57th year

"K-55" was produced until 1957, after which another model appeared - "K-58", on which a 5-horsepower two-cylinder engine was installed, and the gas tank was also increased. In addition, manufacturers changed its shape, which became more streamlined, and modernized the electrical equipment of the machine. The motorcycle "Kovrovets" (photo can be seen below) of the 58th model became the final one in the model range of 125cc "bikes", the release of which was completed in 1960.

The production of K-175 series motorcycles was launched in 1957. These were powerful road bikes, which, along with the 58th model, were produced by the plant until 1960. Later they were replaced by the K-175A model. The 175 series motorcycle was produced until 1965, and the Czech model "Java-ChZ-175" served as its prototype. Motorcycles with a working volume of 175 cm³ had not previously been produced in the Soviet Union, so the appearance of the K-175 model on the market caused quite a stir.

The Czech "Java" was at that time the height of engineering excellence and technical solutions, and therefore the motorcycle "Kovrovets" turned out to be a rather interesting machine - beautiful and powerful, with excellent driving characteristics, and also very comfortable. The K-175V and K-175SM models close the K-series, after which the Voskhod (Kovrovets) motorcycle appeared in 1966 - a machine that is much more comfortable and distinguished by excellent technical characteristics.

Characteristics of the model "K-125" produced in 1946-1951

"Kovrovets" of the 125th series is a one-seater light road motorcycle equipped with a two-stroke single-cylinder 4.25-horsepower air-cooled engine providing a maximum power of 4.8 thousand rpm. The motor cylinder is made of cast iron, which, together with a light-alloy head, is mounted on an aluminum crankcase by means of studs. The motor also houses a variable electric generator "G-35" and a float carburetor of the "K-30" type with a needle-type valve.

The transmission of this model is presented in the form of a three-stage gearbox with a foot switch. The multi-plate clutch is located in the oil sump. The closed tubular frame weighs just over 5 kg, and the total weight of the machine is 84 kg, while the engine weighs 17.5 kg. The dimensions of the base are 1245 × 970 × 675 mm. The maximum speed that this motorcycle is capable of developing is 70 km / h. Note that in 1951 the K-125M model was released, which already weighed 88 kg. It was equipped with a front telescopic fork that mated with a hydraulic shock absorber.

Series "K-55" and its features

The design bureau of the plant carried out developments to modernize the 125th "Kovrovets", and already in 1955 the first model "K-55" was produced. Thanks to the modernization, the speed performance of the Kovrovets motorcycle was increased to a maximum value of 75 km / h. 55 was equipped with a new type of carburetor "K-55", and the rear suspension became pendulum.

Prior to that, in the 125th model, the rear rigid suspension caused significant discomfort while driving and led to the fact that it was necessary to repair the Kovrovets motorcycle (mainly the chassis). The machine was equipped with a single-stroke 4.75-horsepower two-cylinder engine of our own production with a working volume of 123.7 cm³ with an improved cooling system. The motorcycle weighs, like the "K-125", 84 kg. Motorcycle "Kovrovets" model "K-55" was produced by the plant until mid-1957.

About "Kovrovets" 58th model

The 58th motorcycle "Kovrovets" (the photo of which is located above) was a continuation of the previous 55, in which the electrical equipment underwent significant changes. Here, a variable generator was used, which made it possible to abandon the battery, thereby greatly simplifying the process of operating the machine. Also, a speedometer and an ignition switch were mounted in the headlight housing, which became much more convenient for the driver.

The maximum speed of the model reached 80 km / h with a total weight of the motorcycle of 92 kg. The working volume of the single-cylinder 5-horsepower engine remained unchanged. However, the shape of the fuel tank and its capacity were changed, which made it possible to increase the mileage without the need for refueling. The clutch release mechanism has also been redesigned to make it much easier to release. In addition, without a loss of engine power, it was possible to significantly reduce the noise level by installing a muffler of a more advanced model.

Model "K-175"

The device of the engine of the motorcycle "Kovrovets" of the 175th model has now become a short-stroke with one cylinder with a two-stroke working cycle. The volume of the engine was 173.7 cm³ - before that in the USSR, such engines were not used in the production of motor vehicles.

The model began to differ externally from its predecessors: the rear part of the closed design, a protective cover appeared on the carburetor, the drive chain also became protected, a comfortable two-seater seat and a completely new 16-inch wheelbase appeared - this is now the Kovrovets K-175 motorcycle. The technical characteristics also had a significant difference. Judge for yourself: the 8-horsepower motor gave out a maximum frequency of 5200 rpm and was able to accelerate to 80 km / h with a weight of 105 kg.

The 175th motorcycle "Kovrovets" has a 1270 mm base with a ground clearance of 240 mm. The dimensions of the model are 1980 × 1070 × 760 mm. As for the transmission, the box remains a three-stage version with a foot-type gear shifting. Later versions used a semi-automatic squeeze. With regard to the electrical equipment of this machine, it should be noted that a DC system with the use of a battery began to be used.

Modification of "Kovrovets" "K-175A"

In December 1959, a fundamentally new model of the 175 was born - the K-175A motorcycle, the Kovrovets motorcycle. The technical characteristics of the "A" modification were significantly different from the "younger brothers". A four-speed gearbox with a disc-type mechanism was installed on it.

The electrical equipment was based on the use of a variable generator "G-38", which made it possible to do without a storage battery, which was especially significant for the inhabitants of rural areas, where its maintenance caused great difficulties. The front suspension, presented in the form of a rodless telescopic fork, gave a tangible smoothness to the ride of the car.

The design of the air filter has undergone some changes, which began to be mounted on the suction pipe. The mass of the K-175A model is 110 kg. In comparison with the 175th modification, the power characteristics and speed capabilities remained practically unchanged. On the gas tank of modification "A" a new emblem began to flaunt: two hares turned to each other - the emblem of the city of Kovrov, and the inscription "Kovrovets" below.

About Kovrov motorcycle modification "K-175B"

The production of the K-175B series began in 1962. Model "B" was equipped with a new carburetor of the "K-36" brand, thanks to which, at low revs, it was possible to achieve good stable operation of a single-cylinder 9.5 strong engine capable of delivering a maximum number of revolutions of 5.4 thousand.

This made it possible to raise the speed indicator. Now the maximum speed of the car reached 85 km / h, which could be developed from the start in a quarter of a minute, which is almost half that of the K-175A model.

On motorcycles of this series, a variable generator of the G-401 type was installed, which provided more stable performance. The total weight of the machine is 115 kg. The model was produced until 1964.

Series of machines "K-175V"

The first models of motorcycles "K-175V" began to be produced in 1963, which differed in the presence of a cylinder made of cast iron with one exhaust pipe. This decision was made by the engineers of the plant, first of all, to simplify the design and change the gear ratio, but this was not achieved.

There were no particular differences in this model. The same single-cylinder 9.5-horsepower two-stroke engine, which allowed a maximum speed of 80 km / h and a weight of 110 kg. However, later versions already had an aluminum cylinder with two exhaust pipes, which increased the maximum speed threshold to 85 km / h. Externally, the model remained unchanged.

Powerful carpet motorcycles of the K-175SM series

1959 is famous for the fact that Kovrov motorcycles took part in international sports competitions. Thanks to their perfect design and the skill of Soviet athletes, they managed to become prize-winners of races many times. Naturally, the "CM" series is considered the most powerful and technically advanced. It had many differences, including a stable wheelbase, thanks to which winter riding on the Kovrovets motorcycle did not present any particular difficulties for athletes.

Technical characteristics of "K-175SM"

The main difference between the K-175SM is its powerful 12.8-horsepower engine with a piston stroke of 58 mm and a working cylinder diameter of 61.7 mm, which ensured the development of a maximum speed of up to 100 km / h. In addition, the engine was capable of developing a high torque - 1.72 kg * m with a maximum power of 5.6 thousand rpm. The base of the motorcycle is 1270 mm, and its dimensions are 1980 × 1070 × 760 mm with a total weight of 110 kg.

As for the gearbox, it is a four-speed gearbox with an improved gearshift mechanism. In addition, the double-row motor chain made it possible to increase the transmission moment transmitted from the crankshaft to the "primary" of the box.

In conclusion, we add that after the release of the K-175V series of Kovrov motorcycles, in 1966 ZiD launched the production of the first model of the Voskhod motorcycle. Many components of the machines of previous versions have undergone serious revision, which ultimately made it possible to significantly improve the basic performance indicators. This was the beginning of the production of more comfortable and technically advanced products of the enterprise.

For the first time motorcycles "Kovrovets" entered the tracks of multi-day international competitions in 1959. Their debut was quite successful - two out of three athletes who started on the K-175SM won gold medals.

In the future, the design of these motorcycles has undergone major changes. The new "Kovrovets" for multi-day events is significantly different from its predecessor. Let's talk about the ways to upgrade this machine.

Engine. The track of the modern multi-day competition is replete with steep climbs. Therefore, an engine of increased power with good traction is needed.

The team of designers, together with the athletes, have done a lot to improve the K-175SM engine. Compared to the old, the modernized engine with the same basic parameters has higher power (12.8 hp vs. 11 hp), torque and reliability.

During the design of the new cylinder, special attention was paid to the purge. To improve it, the cylinder head is made of the "jockey cap" type. In combination with the specific shape of the blow-off channels, this resulted in a power increase of up to 0.8 liters. With.

Technical characteristics of the motorcycle Kovrovets

Base - 1270 mm
Ground clearance - 240 mm
Dry weight - 105 kg
Dimensions:
length - 1980 mm
width - 760 mm
height - 1070 mm

Main engine parameters
Working volume - 173.7 cm3
Cylinder diameter - 61.72 mm
Piston stroke - 58 mm
Compression ratio - 8.5-9
Ignition advance - 4mm to TDC
Maximum power - 12.8 liters. With.
The number of revolutions - 5600 rpm
Maximum torque (M) - 1.72 kgm
The number of revolutions at M = 1.72 kgm - 4200 rpm
Candle - A11U
Maximum speed not less - 100 km / us
Fuel tank capacity - 12.5 L

The increase in the density of the jet of the working mixture entering the cylinder is achieved by increasing the purge pressure. For this, the diameter of the flywheels has been reduced from 136 to 128 mm (the crank chamber in the crankcase has been reduced accordingly).

Much has been done in the process of fine-tuning the K-28B carburetors. The best results are obtained with a 27 mm diffuser. The length of the outlet pipes has been experimentally established - 490 mm.

We had to rely on the fact that the engine would operate at high temperatures and a rarefied atmosphere, so advanced fins were required. An aluminum jacket with four ribs is pressed onto the upper part of the cast-iron cylinder, the area of ​​which is increased by 350 cm3 in comparison with the previous model.

Compression ratio - 8.5-9 - adopted based on the results of work on B-70 gasoline.

The new piston has three rings, the width of which has been reduced to 2 mm; the first ring is 6 mm from the bottom (instead of 4 mm), and the piston itself is lowered by 7 mm, i.e. the piston pin is displaced by 7 mm to the bottom. This achieves an additional reduction in the crank chamber. Smooth piston ring stoppers are replaced with threaded ones.

Air filter a new one with a suction muffler is used. It is placed under the saddle and is a curved fiberglass socket, into which a mesh basket is inserted, stuffed with a nylon tangle. The basket is locked from above. The filter housing is connected to the carburetor with a rubber coupling. It is isolated from the environment with the help of textinit and BF-2 glue, so that moisture, dirt and dust do not directly enter the filter.

Exhaust device. Currently, deep fords are excluded from multi-day routes, so the muffler pipes could be placed below. This ensures better cylinder cleaning and therefore better engine performance. The design of the muffler is the same as that of the road "Kovrovets-175". The exhaust pipe is welded to its body. This gave the entire system rigidity and reduced exhaust noise. Studies have shown that such mufflers are selected for 0.3 liters. With. capacity is less than modern foreign ones.

Gearbox. The four-speed gearbox has undergone further improvements, in particular the gearshift mechanism. The gears are shot blasted. Instead of a single-row, a two-row motor chain was introduced, which transmits torque from the crankshaft to the input shaft of the box. The crankshaft is mounted on 204 series bearings on the sprocket end and 303 series bearings on the generator end.

With an increase in engine power and an improvement in the dynamics of the motorcycle, the load on the frame increased, so it was significantly changed and made of pipes of Art. 30HGSA.

The height of the steering column is taken at 180 mm instead of 135. To accommodate the filter, the seat post is removed from above, and the swingarm axis is 15 mm closer to the sprocket axis and swings in angular contact roller bearings. The construction of this unit is very rigid, strong and provides high stability.

The described frame has been successfully tested on the roads of the Crimea, the Carpathians and the Austrian Alps.

Front fork: 1 - buffer rubber ring; 2 - reinforcing yoke; 3 - rubber oil scraper ring; 4 - check valve; 5 - hydraulic shock absorber pipe; 6 - fork spring; 7 - thrust bearing of the steering column.

Motorcycle front fork - telescopic, rod, with 150 mm travel. Its springs are made of wire with a diameter of 4 mm (instead of 3.5 mm), their rigidity is 0.46 kg / mm. The fork has good shock absorption on small and large obstacles. Impact energy and unsprung weight on the front wheel and front fork components are absorbed by a well-designed hydraulic system.

The stuffing box seal with an additional felt gasket and rubber oil scraper rings eliminates the passage of the mixture. The fork has an additional reinforcing clip from the pipe. It is mounted on thrust bearings of the medium series (instead of the light one).

The front suspension in the new "K-175SM" is also changed. The volume of the hydrochamber has been increased from 60 to 90 cm3, and the center-to-center distance has been increased from 309 to 330 mm. Thanks to this, the stroke is brought to 90 mm. The hydraulic system is equipped with a device that regulates the vibration frequency and speed of the moving masses. Hydraulic performance is dependent on air temperature, driver and road weight.

The steering wheel is made of pipe 22 X 2 (Art. 30HGSA). Its width is 740 mm. The ends of the pipes are raised and connected by a reinforcing pipe. The shape and dimensions of the handlebars provide a good fit and comfortable handling of the motorcycle. At the ends of the levers, rubber balls are installed to prevent the hands from slipping and injury when falling. The throttle handle has a slot for a backup cable of the carburetor spool.

The rear suspension has a new pendulum arm made of pipes measuring 32 X 2 (Art. 30HGSA). Its tips are made of 7 mm thick sheet and bent at the point of welding to the fork feathers. The swingarm has been lengthened to accommodate 3.5X19 "tires.

The wheels have also undergone major design changes. Mounting and dismounting of tires used to cause great difficulties, the rim was deformed under strong impacts. The rim is now deeper.

The wheel hub is modular, with large flanges and spokes with a diameter of 3.5 mm. It is connected to the driven rear wheel sprocket through a rubber clutch, which improved the operating conditions of the chain and all transmission power units.

The brake drums are made with a diameter of 150 mm. A cast iron sleeve is pressed into the drum of the front wheel. This increases the efficiency of the brakes. Pads made of asbestos-rubber mass are attached with BF-2 glue; rivets are staggered. An annular groove is made in the brake drum, where the annular protrusion of the base of the brake shoes enters. This prevents moisture from entering them. The felt ring is located between the brake drum and the hub flange.

The grip of the wheels with the road, their stability when passing through muddy and sandy areas, oblique descents and bends, as well as when driving on hard and straight sections, largely depend on the profile of the tires and the quality of the rubber. On the motorcycle "Kovrovets-175SM", the tires of the models L-85A, L-131 and Czech "Vachim-59" shown in the photo are used. The speedometer drive has been moved from the rear wheel to the front one.

The saddle is made of latex. It is widened and elongated. Its shape and dimensions give the driver the opportunity to freely change position depending on the nature of the road.

Electrical equipment... Its circuit was developed and tested in five versions. Ultimately, a battery ignition scheme with a G-36M DC generator and a storage battery was adopted, which is used on IZH sports motorcycles. This is done for the purpose of unification.

Two candles are installed in the head, and two ignition coils on the frame. They work in pairs. In case of failure of one of them or the bobbin, by switching the toggle switch, the other is put into operation.

Special equipment. The motorcycle is equipped with control devices SP-15 and a clock. A tool bag with a plate on top is attached to the fuel tank. There are two side tool boxes. On the right side of the frame there is a drip chamber for lubricating the reverse gear chain while driving.

The chain slipping off the rear wheel sprocket is prevented by a special guide.

Motorcycles "Kovrovets-175SM" of the latest model took part in international competitions last season and showed good results. Currently, work is underway to increase engine power, reduce the weight of the machine and further improve its performance.

"Kovrovtsy" for international competitions will lay the foundation for the production of new serial sports motorcycles for stage races.

D. KABAEV, Leading Design Engineer.

Hi! In one of the publications All about moto already told about the motorcycle factory Kovrovets and Voskhod. Now we want to draw your attention to one of the most famous two-wheeled series from this manufacturer. Photos are attached.

Moto K-175 from Kovrov

It is more and more difficult to buy a used version of this bike every year. After all, it was produced a long time ago. The first two-wheeled of the above line rolled off the assembly line back in 1957. After 1965, this iron horse was no longer mass-produced.

What distinguishes this motorcycle from the Degtyarev plant? First you need to pay attention to its unpretentious short-stroke two-stroke engine, equipped with only one small cylinder. The cubic capacity of this power unit was very modest - almost 174 cm³. You cannot raise a farm with such a technique. But the townspeople and villagers in moving long distances benefited from it. And the price of Kovrovtsa K-175 was quite affordable.

An important feature of this steel horse is the presence of a canopy box and a protective casing around the carburetor. At that time, not every Soviet two-wheeled vehicle had such a practical and aesthetic addition. Among the features of the K-175 motorcycle are Kovrovets, which today can be bought in several variations, and the presence of light 16-inch wheels.

Technical characteristics of the motorcycle Kovrovtsa K-175

The low maximum engine power of this motorcycle (8 horses) is achieved at 5200 rpm. This allows the steel horse to reach the maximum recommended speed of 80 kilometers per hour with a substantial weight of 105 kilograms. This bike stood out from the plant. Degtyarev by the presence of chain drive protection. Its area is completely protected from road dust, mud and sand. Interestingly, this iron horse is designed for both solo travel and for two-person riding. Still, its two-seater saddle isn't nearly as spacious. Some motorcycle lines are equipped with a semi-automatic clutch engagement / disengagement mechanism.

Some spare parts for Kovrovets, even in Bryansk or Chernigov, even in Minsk or St. Petersburg, are not easy to find in our time. The fact is that many K 175 motorcycles were produced with a variety of modifications. However, most of these iron horses have a three-speed gearbox and simple rear suspension. The power supply system of these two-wheeled vehicles has a battery (accumulator).

Among the technical characteristics of the moto from Kovrov, there are many noteworthy positions. The bike has a highly efficient system for removing exhaust gases from the combustion chamber. It is represented by a pair of mufflers. The two-wheel cylinder is made using cast iron as the main material.

The "K 175" of the first years of production had a much smaller mass than the bikes of 1962-1964 released from the assembly line of the Degtyarev plant. Since the beginning of the sixties of the last century, representatives of the above series received an additional letter as a prefix to the name. For example, "K-175B". Modified two-wheeled ones from Kovrov received other carburetors, which made it possible to increase the maximum speed indicator.

The changes also affected the Kovrovtsev cylinder, the photos of which you will see in this article. The manufacturer began to replace the cast iron versions with their counterparts made of aluminum alloy. Such actions allowed to significantly increase the power of the bike.

It is curious that the moto factory in the city of Kovrov also produced sports motorcycles K 175. These iron horses were used in various competitions. They had a boosted single-cylinder engine, an updated clutch mechanism, and a more durable chain drive. Strengthening also touched the frame of the two-wheeled sports Kovrovets. Many of its parts became super-durable.

juodpamdodeyaramsu MOTORCYCLE TO - a light road car with * 5.5 hp engine. With. It is quite possible to raise it to 6-6.5 liters. With. and even higher. First of all, for this purpose you need to stock up on a tool: a set of files, needle files, sandpaper. The removed engine is thoroughly washed in kerosene, the muffler and exhaust pipe are cleaned from carbon deposits. Now you can start forcing. But first you need to unroll the cylinder. To do this, lubricate the mirror of the cylinder with a thin layer of oil, cut out a sheet of paper measuring 118 X 162 and, inserting the rolled paper into the cylinder, push through the contours of the windows. Now the resulting scan must be compared with the scan shown in the figure (previously drawn at a scale of 1: 1), and it will become clear how much it is necessary to cut this or that window. The vertical drills of the cylinder purge channels are sawed along the contour of the crankcase channels until they match. It is quite clear that the transition from one section of the channel to another should be as smooth as possible, and the surfaces of the channels should be cleaned of irregularities and polished. The edges of the cylinder windows should be rounded off with a radius of 0.3-0.5 mm. Now you can grab the end of the cylinder head. It needs to be sawed off so that the height of the sphere is equal to ZPYAL11NoZh && SH1YAM -1 03 "-" * - ^ = "ll, u ,.<лг^.Лг,16,5 мм. Это соответствует степени сжатия 8,5. Сняв фаску под углом 30 градусов, мы получим диаметр сферыс фаской, р авный 53,5 мм. Сферу головки цилиндров и поршень тоже надо тщательно заполировать. Собрав вновь двигатель, приступают к его регулировке. Для этого устанавливают опережение зажигания 3,5—3,7 мм до в. м. т. (при зазоре в прерывателе 0.4 мм), прогревают его на средних оборотах, з акрывая рукой половину щели воздухофильтра. Если обороты вала двигателя увеличиваются — значит, смесь обедненная, если резко падают — смесь обогащенная, если падают медленно — смесь нормальная. Если же обороты не изменяются, следует искать подсос воздуха в соединении карбюратора с фильтром или цилиндром, в прокладках, сальниках и др. Изменяя положение дроссельной иглы или меняя жиклеры, можно добиться нормальной смеси. Категорически запрещается разгонять двигатель без нагрузки до максимальных оборотов, т аккакчерез 25—40 секунд подшипник нижней головки шатуна выйдет из строя. , Для проверки регулировки в дорожных условиях на ровном участке разгоняют мотоцикл на всех передачах до максимальной скорости, добиваясь нормальной рабочей смеси. Смесь нормальная, если разгон на пер-Развертка цилиндра двигателя М-103 повышенной мощности. Пунктиром обозначены контуры окон серийно выпускаемого цилиндра. вой передаче быстрый ик концу его двигатель начинает работать «через такт»; на второй передаче разгон нормальный, иногда в самом конце его двигатель начинает работать «через такт»: разгон на третьей передаче нормальный, двигатель работает нормально, не «поет» и не работает «через такт»; при этом развивается максимальная скорость. Чтобы отрегулировать карбюратор в дорожных условиях, надо наклонить его или поднять (а если нужно — опустить! дроссельную иглу. Не следует снимать контактно-масляный фильтр или удалять решетки глушителя: заметного увеличения мощности это не дает. РУБЕЛЬ, инженерг. Минск«КОВРОВЕЦ-175» ".4SS*»hieMV^SfU^SH»9№iKtMK,хода, обогащение смеси достигается завинчиванием регулировочного винта. обеднение — отвинчиванием. У К-36 это делается при помощи двух винтов — установочного, регулирующего степень подъема дросселя, и винта, регулирующего количество смеси. Самая трудная и кропотливая часть работы — подбор главного жиклера. Дать какие-либо определенные рекомендации очень трудно, многое зависит от индивидуальных особенностей двигателя. Двигатель «Ковровца-175» р азных моделей после доводки может развить мощность до 11 л. с. при 52005400 об/мин. Чугунный однопатрубный цилиндр мотоцикла «Ковровец-175В», установленный в картер спортивного мотоцикла «Ковровец-175СК> , with the addition of an aluminum nozzle, made according to Fig. 3, gives a power of 11 hp. With. without changing the valve timing, but with a compression ratio of 7.0-7.5. The nozzle is machined from aluminum. Its purging channels are milled to coincide with the purging channels of the cylinder and crankcase. It is necessary to process the canals up to the seventh cleanliness class. The attachment is heated with a gas burner and slid onto the cylinder. The joint is pre-coated with bakelite varnish or BF-2 glue - this ensures the tightness of the channels. The inlet window is milled in place or prior to pressing. Pay particular attention to the coincidence of the purge passages and the inlet port if it was milled prior to pressing. As the engine power increases, an increased load is transferred to the clutch. Therefore, it is necessary to add one plastic and one metal disc to the existing clutch, or turn all the pressure springs one turn, and cut off the protruding coils of the spring flush with the clutch drum. X. MIROPOLSKIY, V. UTKIN, engineers Fig. 1. A set of tools for forcing the K-175 motorcycle: a - devices for screwing in emery cloths: b - steel cutters; c - w aroshkas with a grinding stone; d - flat file, round; d - scrapers; e - round and square files. Fig. 2. Development of the Kovrovtsa-175 cylinder. Dotted lines indicate channels before forcing, solid lines - after forcing. Rice. 3. Aluminum nozzle. For the "Kovrovtsa-175" engine, when operating on A-66 gasoline, the compression ratio should not be higher than 7.5, on A-72, A-74, B-70 gasoline, it can be raised to 8, 5. But at the same time, it is desirable to use MC and MK oils. The set of tools required for forcing is shown in Fig. 1. Increase the compression ratio by undercutting the cylinder head. This must be done so that the surface finish is at least sixth grade. The size to which you want to trim the head is determined empirically. The combustion chamber should be carefully polished with a fine sandpaper to reduce carbon build-up and improve blowdown. To create a good tightness, the seating surface of the head and cylinder is carefully lapped with paste. Connect them without a gasket - to improve heat dissipation. Determine the compression ratio on a fully assembled engine. pouring oil from a beaker. The volume of the mixture to be poured at a compression ratio of 7.5 should be 27 cm ", at 825 cm", and at 8.5 - 23.5 cm3. To lighten the piston, it is advisable to cut off the base belt at the bottom. If you polish the piston crown, its heat stress will decrease. The rings in the grooves should sit with a clearance in height of 0.05–0.07 mm. The dimensions of the windows are adjusted according to the scan shown in Fig. 2. Large layers of metal on the cylinder liner are very well and quickly removed with cutters using a pneumatic gun or electric drill, and if they are not there - with a semi-personal file. In all cases, the windows are sanded with an emery cloth. The channels in the aluminum jacket of the cylinder are sawn to the windows with files, scrapers, emery cloths and processed until a flat surface of the seventh cleanliness class is obtained. There should be no mismatch between the channels of the cylinder jacket and the windows. The blowing channels are not enlarged, but they are filed according to the template to the channels in the crankcase and grinded. The misalignment of the channels of the cylinder crankcase should be within 0.1-0.2 mm. In fig. 2, dashed lines conventionally indicate channels before forcing, solid lines - to channels after forcing, as well as channels that do not change shape after forcing. When all the work on fine-tuning the engine is completed, the parts are washed in kerosene. The last step is carburetor adjustment. At idle speed, the quality of the mixture is regulated at the K-55V carburetor by the idle adjusting screw "V4V5Macr.:ttrA*.nrcil% ^:" A4VbT- "iW: V" "ii4? ^^^ Д