How to install and adjust the carburetor on Izh Jupiter 5

Jupiter 5 is one of the most successful creations of Soviet motorcycle production. Today, like 30 years ago, the device is often found on the streets of both remote outbacks and large cities, and, in most cases, the owner prefers to handle its maintenance independently.

The carburetor, being one of the most important components of any motor vehicle, is subject to intensive use and increased wear. Considering the great age of some models, replacing this module very often becomes an inevitable condition for extending the life of the unit.

The motorcycle is equipped with Izhevsk carburetors K-62D, K-65D, K-68D , or the Czechoslovak model Jikov-2928SE . There are few differences between the first two options: the design of the top cover; enrichment jet diameter; needle fastening (K-65D comes with a nozzle). The K-68D differs from its predecessor:

• Enlarged diffuser.
• A round (not square, like the K-65) damper.
• Lateral (more convenient for optimization) location of the idle screw.
• Threaded (for quick needle adjustment) top cover.

Which carburetor is better to install on IZ Jupiter 5? As you can see, the 68th model is more convenient to maintain , however, experienced motorcyclists note that it often contains defects, for example, in the form of the absence of a hole that improves the formation of the fuel mixture.

Jikov-2928CE is considered a higher quality carburetor, but also more difficult to operate and repair. Therefore, when choosing this option, you should prepare for possible difficulties, for example, when searching for replacement jets, because their size is much smaller than those from Izhevsk.

Rice. Carburetor K-62:

1 — idle fuel jet, 2 — main fuel jet; 3 — float chamber, 4 — sprayer; 5 — float axis, 6 — float lever bushing; 7 — air channel, 8 — nozzle, 9 — dosing needle, 10 — body; 11 — throttle, 12 — needle lock; 13 — throttle spring; 14 — throttle lift limiter (removed after engine break-in); 15 — throttle control cable, 16 — rod with idle speed adjustment screw (lowering the throttle); 17 - cover; 18 — idle speed adjusting screw, 19 — fuel inlet fitting, 20 — adapter hole, 21 — idle speed emulsion channel; 22 — drainage hole, 23 — idle air channel, 24 — locking needle with washer, 25 — float, 26 — corrector emulsion channel; 27 — dosing needle; 28 — float stopper, 29 — plunger, 30 — plunger spring, 31 — corrector control cable

How to adjust the K-62 carburetor

The basic K-62 carburetor has long become the main one on all models of domestic motorcycles. According to its creators, this device was supposed to significantly improve both the starting and operational performance of motor vehicles.

In practice, unfortunately, this did not work out that way. There are much more complaints about the performance of these carburetors than all those that preceded them. And it would be good if we were talking about the fact that the promised efficiency or acceleration is not provided. Sometimes the motorcycle just doesn't go at all.

If we completely exclude incredible mechanical causes (complete blockage of the jets, lack of a shut-off valve and some other fantastic defects), which are indeed extremely rare, then only one assumption remains: the carburetor is out of adjustment. Today we will talk about how to return him to normal abilities.

To begin with, let us remember that with the throttle valve fully closed and its lift very low (20-30%), only the carburetor idle system works. At medium speeds and at a throttle position of 1/3 to 3/4 stroke, the sprayer and metering needle operate. In the last quarter of the throttle stroke, in fact, only the main fuel jet somehow influences the processes

Where to start?

If the carburetor is new, check that it is well flushed. Sometimes a clot of preservative lubricant can conceal the remains of chips or castings and clog thin channels. This means that it must be washed and blown with dry air.

Then you should make sure that the carburetor is tightly secured to the cylinder pipe, and the pipe, in turn, is tightly connected to the cylinder. If this is not done, air leaks at the joints will negate all your tricks and make such adjustments to the composition of the mixture that nothing can be taken into account or corrected. Whenever possible, the planes must be checked and ground against a surface plate. And then use a gasket made of a sufficiently elastic, petrol-resistant material. At the same time, try to adjust the gasket to the dimensions of the window as accurately as possible so that it does not protrude inward in any way - this can create a noticeable obstacle in the path of the mixture and worsen the filling of the cylinder. Typically, thick cardboard or paronite is used to make gaskets. Although sometimes motorcyclists use thick, relatively soft, gas-resistant rubber, motivating their choice with the desire to somewhat reduce the vibrations transmitted from the cylinder to the carburetor. There is a certain reason for this.

After the initial troubles are left behind, you can move on to the actual adjustment. It starts with checking and setting the fuel level.

Video: Adjusting carburetors K62, K65

Adjusting mixture enrichment

Before starting adjustments, be it the carburetor model K 65 of the Ural, Dnepr motorcycle, Buran snowmobile or other vehicles, the engine should be warmed up.

Then the minimum stable idle speed is set. To do this, use the screw to lower the throttle. Afterwards you need to increase the number of revolutions to the maximum possible. The screw is rotated in one direction or another.

Slowly the speed is again reduced and increased. This should be done 2-3 times.

After the manipulations, you should check how the engine reacts to the position of the throttle. To understand how to set up the K 65 carburetor, you need to determine the required level of enrichment of the fuel mixture for the engine.

To do this, carry out such an experiment. The throttle opens sharply. If the engine stalls, then the mixture should be enriched. To do this, turn the mixture quality screw 1/4 or 1/2 turn.

A stalling engine when the throttle is closed sharply indicates the need to make the mixture leaner. In this case, the mixture quality screw needs to be adjusted by 1/4-1/2 turn.

Stop valve

When checking the K-68 carburetor, you should pay attention to the shut-off valve. This valve has another name - a needle. It is he who can get a rich mixture due to the fact that the valve is not tightly attached.

The needle-type valve contains a rubber ring in its assembly. During the inspection, you can pay attention to the condition of this element. To do this, you need to remove the cover, which is located at the bottom. It is secured with two bolts. When removing these elements, you need to ensure that the gasket is not damaged.

After this, you need to remove the float. To achieve this, you need to squeeze the float rod out of the grooves. During this process, you need to watch the needle, as it can easily fall. Notice how the needle moves along the saddle. If the movement occurs without failures, then everything is normal. If the ring is worn out, it is necessary to replace this element.

Jupiter 5 is one of the most successful creations of Soviet motorcycle production. Today, like 30 years ago, the device is often found on the streets of both remote outbacks and large cities, and, in most cases, the owner prefers to handle its maintenance independently.

The carburetor, being one of the most important components of any motor vehicle, is subject to intensive use and increased wear. Considering the great age of some models, replacing this module very often becomes an inevitable condition for extending the life of the unit.

The motorcycle is equipped with Izhevsk carburetors K-62D, K-65D, K-68D, or the Czechoslovak model Jikov-2928SE. There are few differences between the first two options: the design of the top cover; enrichment jet diameter; needle fastening (K-65D comes with a nozzle). The K-68D differs from its predecessor:

• Enlarged diffuser.
• A round (not square, like the K-65) damper.
• Lateral (more convenient for optimization) location of the idle screw.
• Threaded (for quick needle adjustment) top cover.

Which carburetor is better to install on IZ Jupiter 5? As you can see, the 68th model is more convenient to maintain, however, experienced motorcyclists note that it often contains defects, for example, in the form of the absence of a hole that improves the formation of the fuel mixture.

Jikov-2928CE is considered a higher quality carburetor, but also more difficult to operate and repair. Therefore, when choosing this option, you should prepare for possible difficulties, for example, when searching for replacement jets, because their size is much smaller than those from Izhevsk.

Rice. Carburetor K-62:

1 — idle fuel jet, 2 — main fuel jet; 3 — float chamber, 4 — sprayer; 5 — float axis, 6 — float lever bushing; 7 — air channel, 8 — nozzle, 9 — dosing needle, 10 — body; 11 — throttle, 12 — needle lock; 13 — throttle spring; 14 — throttle lift limiter (removed after engine break-in); 15 — throttle control cable, 16 — rod with idle speed adjustment screw (lowering the throttle); 17 - cover; 18 — idle speed adjusting screw, 19 — fuel inlet fitting, 20 — adapter hole, 21 — idle speed emulsion channel; 22 — drainage hole, 23 — idle air channel, 24 — locking needle with washer, 25 — float, 26 — corrector emulsion channel; 27 — dosing needle; 28 — float stopper, 29 — plunger, 30 — plunger spring, 31 — corrector control cable

Carburetor characteristics for 68

Owners of motorcycles that were produced in Soviet times often use the K-68 Pekar carburetor. This equipment is produced in the city of St. Petersburg. Basically, such products were installed on various domestic vehicles.

The series called “Baker” contained a large number of diverse devices. Carburetors of this type were most often found in cars, as well as in motorcycles. For several years now, the demand for these products has not decreased. This happens because equipment of this type has high functional characteristics. These mechanisms are also quite economical.

The K-68 type carburetor is in great demand among car owners. This happens due to a number of reasons. For example, with proper adjustment of this carburetor, gasoline consumption can be reduced by up to 20 percent. In this case, the performance characteristics of the motor will increase significantly. The carburetor from this series also has acceptable performance properties. This mechanism has another significant advantage - its price. It is these characteristics that make this carburetor competitive with others.

Dosing system

The components of the dosage system are the main fuel jet, atomizer, air supply channel and throttle needle.

The entire system operation process occurs according to the following scheme. From the float chamber, fuel enters the atomizer through the main jet. Under the influence of liquefaction, it rises along the gap between the throttle needle and the nozzle. At the exit from it, the fuel is mixed with air, which entered through the hole in the atomizer body through the channel.

The K 65 carburetor has the following engine control system. The throttle needle can be set to one of five positions. This ensures that the engine operates at medium speeds. But at the highest power, it should be taken into account when tuning that the carburetor of the K 65 model determines the fuel consumption by the throughput of the main fuel jet.

There is a lock washer installed under the fuel pipe. It secures the nozzle.

Carburetor of Izh Planet Sport motorcycle

Motorcycle Izh Planet Sport 350. A legend of the Soviet motorcycle industry. Early models of the motorcycle were equipped with Japanese components, in particular a Mikuni carburetor with a diffuser diameter of 32 mm. Thanks to him, the motorcycle's power was 32 hp. at 6700 rpm.

The reliability of the carburetor is explained by the simplicity of the design. The throttle has a cylindrical shape. To drain excess fuel, there is a special plug at the bottom of the float chamber. The carburetor is adjusted using an air screw and an idle screw (similar to the K-68). To make starting the engine easier in cold weather, there is an enrichment lever.

Later versions of the motorcycle began to be equipped with the domestic K-62M carburetor. The engine power with it dropped to 28 hp.

As you can see, different carburetors were installed on Izh motorcycles of the Planet line, but mostly domestic ones. As engine power increased, the characteristics of carburetors also changed. For high-quality and long-term engine operation, it is necessary to inspect and clean the carburetor in a timely manner (every 3000-4000 km). If desired, imported carburetors can be installed on Izh Planet motorcycles. The main thing is to choose the right jets with the required throughput and match the diameter of the diffuser.

source

Video: Setting up the K68i carburetor on IZ Jupiter.

Carburetor synchronization

After tuning, the K 65 carburetor (Ural) must be synchronized. This can be conveniently done using a tachometer. In the absence of such equipment, synchronization can be performed using the speedometer.

To do this, place the motorcycle on a stand and start the engine. 4th gear is set. Remove the cap from one of the spark plugs and adjust the speedometer reading to 50 km/h. The gas handle is fixed with a bolt.

One cylinder turns on and the other turns off. The length of the cables is adjusted using fittings. At the same time, they achieve the same speedometer reading.

When removed, the spark plug cap must be grounded and shorted to the ground of the motorcycle. In this way you can adjust the Ural carburetor.

Idle system

Another important system that must be taken into account when adjusting the K 65 carburetor is the idle speed device.

The presented system consists of a fuel pipe, an air channel, an idle hole, mixture quality and quantity screws, and a transition hole.

When the engine operates at low speeds, an emulsion is formed. This occurs by raising the fuel through the tube under the influence of vacuum in the mixing chamber. The fuel is combined with air, which enters through the channel. The K 65 carburetor assumes that the emulsion exits at low speeds only through the idle hole.

As the speed increases, the vacuum in the hole area increases. The same emulsion also begins to flow through it. So the fuel supply increases as the engine speed increases.

Adjusting the K62 carburetor:

Hello! Please tell me, I have a Minsk 125, it’s a Pakko (original, new), it’s not in use, it works fine, that is, the idle is normal, it picks up speed briskly, but as soon as you start to move out of place, it doesn’t pull well, or it may even stall, you just need gas open more than halfway. The quality screw is screwed in completely, but if you unscrew it by 1-1.5 rpm, you won’t be able to move it at all - the engine will stall. The spark is normal, the ignition is set correctly, the needle is in the middle position. Please tell me what’s wrong, this is the first time I’ve encountered such a problem?

Video: Adjusting the Carburetor on a Soviet Motorcycle!

Adjusting the fuel level

Adjusting the K 65 carburetor begins with setting the fuel level. To do this, turn the device over and remove the bottom of the float chamber. Next, replace the distance from the connector to the line that divides the float into two parts.

This distance is usually 13 mm with a possible deviation of 1.5 mm in both directions.

If the size on the carburetor does not fit into these frames, you should bend the float tongue in the desired direction.

It happens that the K 65 carburetor is configured correctly, but it begins to “overflow.” This means that the float has leaked.

Testing this theory is easy. You need to fill the bath with warm water and immerse the float in it for a minute or longer. If bubbles appear, the float is faulty.

Basic types of carburetor settings

It is no secret to any car owner that the carburetor is designed to prepare a combustible mixture for the engine, which it produces by mixing a certain portion of air with fuel. But its functions are not limited to this. It must also ensure that the motorcycle engine operates in different modes, which means preparing a fuel mixture with different proportions of its components. The implementation of this task is entrusted to various systems and components of the device. These include:

• Main dosing system;
• Idle system;
• Starting device;
• System for maintaining a given fuel level.

We will look at setting up these elements. The best place to start is by checking the fuel level in the float chamber. To do this you need:

• remove the carburetor;
• remove the float chamber cover;
• Having turned the carburetor over so that the floats are on top, measure the distance from the edge of the body to the top edge of the floats. It should be 26 mm ± 0.5 mm; in case of deviation, it is eliminated by bending the tongue;
• check the parallelism of the floats; adjust by bending the brackets.

Now let's move on to the main dosing system. First, check the gap between the throttle valve and the bottom of the air duct. It should be 2 mm. If the gap does not match, then adjust it using the throttle valve cable adjusting bolt, which is located on the throttle well cover tube.

The next step in adjusting the K-68 carburetor is to check the position of the throttle needle. It has 5 grooves into which the needle lock can be inserted. The normal position of the lock is the middle groove. Moving the lock downwards makes the mixture richer, upwards - on the contrary, it becomes leaner. We check by the color of the central electrode of the spark plug:

• if the electrode is black or dark brown, this means that the combustible mixture burning in the cylinder block is highly enriched - move the lock down;
• if the color is light gray, it is depleted - raise the lock;
• The light brown color of the electrode indicates the normal position of the needle.

Now the carburetor can be reinstalled and the idle speed adjusted. The adjustment is made on a hot engine, so you can drive 10 - 15 km before adjusting. Next, we make adjustments in the following order:

Golden rules for tuning the ignition on Jupiter: cheat sheet for IZhovodov

Many owners of Izhmash equipment set the ignition themselves. This process is not difficult if you understand the structure of the system and the principle of operation. The article provides instructions on how to set up the ignition on a motorcycle, including the IZ Jupiter 5.

In what cases is ignition adjustment necessary?

During the operation of the vehicle, the owner faces many problems. The most serious failure is related to the engine. In order to spend significant funds on major repairs, it is necessary to monitor the technical condition of the motorcycle and carry out preventive work, including adjusting the valves and valves (video author - Hana Rulyu).

If you do not monitor the SZ, then the motorcycle engine may not reveal its full potential and will not work at full capacity. This can lead to a reduction in its service life. An ignition adjustment is necessary if the engine is running poorly, the muffler or carburetor is firing. True, before setting up the SZ, you should make sure that the cause of the malfunction is in it.

It happens that the flywheel bolt, which connects the two halves of the crankshaft, comes loose, begins to play and does not work well. Sometimes he even cuts the key.

Setting up the SZ may be necessary after repairing the ignition switch Izh Jupiter 5. The installation and connection itself are carried out according to the diagram.