Izh Jupiter 5: Technical characteristics of the motorcycle in the Best review

The IZH Jupiter 5 motorcycle is a well-known monster of the Soviet motorcycle industry, produced from 1987 to 2008. Massive and archaic, it represents a superficial reworking of previous generations of the series, in which the designers attempted to correct their shortcomings with relative success. Due to good suitability for rural areas the bike quickly became popular; moreover, due to a different engine, it was superior in power to its main competitor, the fifth “Planet”. Its engine was considered successful, and it was borrowed for another model of Izhevsk Motorcycle, the first Russian cruiser, which at one time was used even by traffic police officers.

Design

It would be naive to expect design delights from Soviet motorcycles. The bike looks similar to all other models produced by motorcycle factories of those years, but this is not surprising - the fifth generation was developed on the basis of the fourth, and the fourth - on the basis of the third, created back in the 70s of the last century. But many bikers, nostalgic for the old days, appreciate this rugged simplicity. Moto Izh Jupiter 5 does not stand out in any way externally from other bikes from the times of the USSR, which you can easily see for yourself by looking at the photo.

Technical characteristics of Izh Jupiter 5

In general, the characteristics of the Izh Jupiter 5 motorcycle corresponded to its time. But in the 2000s, when it continued to be produced, it could no longer compete with imported models. The Chinese had already flooded the market with budget, but still more modern models, and a flood of used motorcycles poured from Japan, Europe and the USA. The characteristics of the Izh Yu5 engine were not bad, but everything else was hopelessly outdated a couple of decades ago.

Engine

The technical characteristics of the engine are not amazing - two cylinders, 347 cubic meters . There is enough horsepower, as much as 24 , torque - 34 Nm . Compared to the previous generation, the engine lost 4 hp, but gained torque, and there was also noticeably more thrust at the bottom, so in general the characteristics of the Izh Jupiter 5 became more balanced. But the engine remained two-stroke , and oil mixed with gasoline must be poured into the gas tank in a ratio of 1 to 25 . But it can easily digest even AI-76, not to mention AI-80. The declared maximum speed is 125 km/h , and it can be achieved on Jupiter without a stroller. And if you look at the engine in cross-section, it turns out that it subtly resembles all the engines at once that were ever produced at the Izhevsk Motor Plant.

Transmission

Standard 4-speed transmission , where first gear is downshifted and all others are upshifted. It has never been reliable, but thanks to its high maintainability and availability of spare parts, Soviet motorcyclists quickly learned how to solve problems on their own. Some garage craftsmen even completely rebuilt the transmission, adding a fifth gear to the bike, but these were custom ones.

Chassis and brakes

The chassis was developed back in the 70s, if not earlier, and in Jupiter 5 it has remained virtually unchanged. A conventional steel frame with a telescopic fork in front and ancient shock absorbers a la “candle” in the rear, plus drum brakes on both wheels. The effectiveness of the suspension and braking system was mediocre even for its time, but they also had a significant advantage - endurance and maintainability. On modern motorcycles (except perhaps enduro), oil from the fork quickly begins to leak on rural dirt roads, and Izh Yu5, it seems, can ride without it at all. But we still do not recommend .

Electronics

The fifth generation Jupiter does not have the same electrical problems that the fourth had. In fact, this model is the same Jupiter 4, but with a number of corrected shortcomings, such as regular wiring problems. Gasoline consumption has also become lower thanks to a redesigned ignition. In general, the electrical circuit has changed slightly, but the weak points that regularly served as a source of headaches for owners have been removed.

Weight and dimensions

The dimensions of the bike can be called average, as well as its weight. How much does Izh Jupiter 5 weigh? By modern standards - quite a lot, about 160 kg , and this is only dry weight . But the motorcycle engine is located low, so the center of gravity is also shifted down. The relatively large weight is due to the fact that in the USSR they did not skimp on hardware, and plastic elements were practically not used. If something can be made from iron, it must be made from iron! That is why the weight of the Izh Jupiter 5 engine is about a quarter of its total mass, if we consider the specimen without a sidecar.

Controllability

This mastodon handles mediocrely , and not least because of the ancient design, and with a stroller the handling becomes even worse. But the cradles for Izh Jupiter 5 were also produced separately, so if you don’t need it, you can always disconnect it. But don't forget about weak brakes , which are not enough to effectively stop a massive bike. On the other hand, the Izh stroller is good because you can load a lot of spare parts and other goods into it when going on a long trip, since its volume allows this.

Fuel consumption

Compared to the previous generation, gasoline consumption has noticeably decreased, from 7-8 liters to 5.5-6 . The declared figures are about 5.9 liters at an average speed of 90 km/h . The quality of gasoline does not matter; the carburetor calmly consumes everything that burns. Tank volume - 18 liters .

Model features

The main feature of the motorcycle is that it can be used with or without a side trailer. If we look at the design, it resembles the IZH Planet 5. A distinctive feature is the simplicity and beauty of the style, unique cylinder fins and completely new flange mounts on the exhaust pipes have appeared. The shape of the dashboard has become square, there is also a turn signal, low/high beam, ignition switch and speedometer. Due to the increase in seating, the shape of the tank has also changed.

The peculiarity of the model lies in the parameters related to weight and dimensions:

The ground clearance in different versions is 13.5 cm.
Wheelbase – 145 cm.
The length of the motorcycle is 217 cm.
Full width 81.5 cm.
Height 117 cm.

Among residents of rural areas, the motorcycle has gained the greatest popularity.
The weight of the Izh Jupiter 5 motorcycle reaches 160 kg, this helps the vehicle to be stable and maneuverable. If a side trailer is attached to the model, then the weight becomes 255 kg. The motorcycle can easily withstand a load of not only 170 kg, it can easily transport heavy loads, and there is no risk of wear and tear.

On the market Izh Jupiter 5 can be found in three modifications:

The standard model is a motorcycle without a side trailer, but with mounts for a sidecar if necessary.
The tourist model is equipped with a stroller and has an additional spare wheel with special lugs.
Izh Jupiter 5 luxury class comes without a side trailer and has no fastenings. But there is a compact fairing and several knee roll bars. Additionally, this model has a trailer rack.

Repair and tuning

The products of the Izhevsk plant have never been famous for their reliability. But there is also an advantage in this - being the first motorcycle for a novice biker, some “Izhak” acted as a “learning desk”, helping to learn not only driving, but also independent maintenance and repair.

Repair

The gearbox
causes complaints . It works clumsily, and problems sometimes arise with it, as with the clutch.

Spare parts

Finding them is not difficult, because at one time the Izhevsk plant riveted a fair number of motorcycles. The prices are low, but in some cases it is cheaper and easier to buy a “donor”, from which you can remove everything you need as needed.

Tuning

It is not easy to somehow modify a Soviet bike. Typically, owners reduce all changes made to visual tuning. Sometimes the carburetor is replaced with a Japanese or Chinese one - this relatively inexpensive operation helps avoid many potential problems.

Disadvantages and childhood diseases

The car is not without its drawbacks, for which many people do not like it. Most of them manifest themselves as a result of improper operation or overheating of the engine in difficult road conditions. The most annoying are the following disadvantages:

Rapid wear of parts of the cylinder-piston group and crankshafts.
Low resource of chain drive parts.
Uneven operation of the cylinders.
Poor quality connectors of electrical equipment wires.
Imperfect, archaic design of attaching the saddle to the frame.

Wear of the main engine parts causes the most problems for motorcycle owners. Even correct and careful operation is accompanied by early wear of pistons, cylinders, and crankshaft parts. With a new engine, after running 15-20 thousand km, extraneous metallic sounds appear, which intensify over time. They can be caused by one or more reasons:

Wear of the connecting rod upper head bushing.
Cylinder wear.
Wear of the piston skirt.
The lock falls out of the piston ring groove and is broken.
Destruction of the connecting rod needle bearing on the crankshaft.

These defects can only be eliminated by replacing parts of the next repair size, boring the cylinders and bushings. All of this work, except for replacing the crankshafts, can be performed without removing the engine.

Poor quality of chains or inattention to the condition of rubber boots lead to rapid wear of the drive . At the same time, the drive sprocket wears out just as quickly and must be replaced along with the chain. The rear gear lasts longer and can survive 3 or even 4 chains.

It’s rare that an engine is characterized by perfect uniformity of cylinder operation. The primitive mechanism for adjusting the distribution of fuel mixture flows across the cylinders does not allow precise adjustment of the supply. As a result, each cylinder produces its own torque . Although the difference is not great, the load on the crank system is not uniform and balanced. As a result, it works with a skew in the values of the force vectors; the more loaded crankshaft quickly fails. The presence of unevenness can be easily detected by the color of candle soot . The color of the carbon deposits on the spark plugs should be the same; if there is a significant difference, then this primarily indicates uneven operation of the cylinders. It can be adjusted, but the regular process is poorly managed and laborious.

Electrical wiring is made with low quality wires and connectors . Cases of contact oxidation or wire breakage as a result of vibration of a loose connection are a widespread phenomenon.

The design of fastening the saddle to the frame has not changed since the appearance of the first IZhs of a similar arrangement in the early 60s. After a short period of use, the lock becomes loose due to vibration, and unpleasant play appears in the joints. Under the saddle there are connectors from the wires going to the optics of the rear flap and to the side trailer. Many owners, forgetting about this, simply tear the wires under the saddle when removing it. The rear wheel cannot be removed without removing the seat.

Motorcycle modifications

The basic model had the index IZH 6.113 - 010 - 01, and the version with a side stroller - 6114 - 010 - 01. The “ Lux ” modifications were also produced (cradle, spare wheel, toothy tires, fairing, protective arches, trunk) and “ Tourist ” ( the same thing, but without the fairing, trunk and arches). Subsequently, the bike was modernized many times, receiving a different carburetor, a disc front brake, and a more energy-intensive fork with pneumatic adjustment. There is also a version with a cargo side trailer, but this is vanishingly rare these days. Jupiter 5 of the transitional model also comes across on sale, but this definition usually hides just one of the early modifications.

Fifth launch of Jupiter

New motorcycles “IZH-Jupiter-5” and “IZH-Jupiter-5K” (their industry standard indices are IZH-6.113 and IZH-6.114) began rolling off the assembly line of the Izhmash association. When developing these motorcycles, the designers tried to take into account as much as possible the comments and wishes expressed by the owners of the fourth generation Jupiters. They concerned mainly electrical equipment, efficiency, and engine adaptability to changing driving conditions.

IZH-Jupiter-5 received an engine with a more high-torque performance and improved electrical equipment.

Jupiter-5 has a thoroughly modernized engine. By selecting the most favorable valve timing and improving cylinder purging, the traction and dynamic qualities of the machine have been increased. The most gratifying thing is that the so-called adaptability coefficient has increased, which characterizes the engine’s ability to maintain speed while increasing resistance to movement, also called operating flexibility. This is especially important when driving with a stroller on dirt roads or rough terrain.

New side trailer that can easily be converted from passenger to cargo. A spare wheel with an all-terrain tire is visible.

How does the performance of the new engine compare to the old one? The graphs show that the maximum torque increased from 3.4 to 3.5 kgf•m, and the speed at which it is achieved became 600-900 rpm lower. The minimum stable speed has also decreased - to 1300 rpm. The power curve (external characteristic) of the engine has changed favorably. By sacrificing four forces of maximum power (24 versus 28 hp for Jupiter-4), we managed to increase it by 1-2 hp. With. power developed at average, most frequently used speeds. The rotation speed corresponding to maximum power is also reduced - to 4800-5600 rpm (for the “fourth” - 5600-6200 rpm).

Comparative external characteristics (power depending on the speed) for IZH-Jupiter-5 (dashed line) and IZH-Jupiter-4 (solid line).

Comparative graph of the acceleration time of IZH-Jupiter-5 (dashed line) and IZH-Jupiter-4 (solid line).

Behind these numbers and graphs there is a real benefit for the motorcycle owner: now, even with a full load, it easily accelerates and moves confidently in higher gears, so you have to switch them much less often than on Jupiter-4. We hope that both rural motorcyclists and city drivers will appreciate this quality.

Fuel consumption has decreased: the target figures are 5.9 l/100 km versus 6.2 for a single motorcycle and 7.1 instead of 7.5 l/100 km for a motorcycle with a sidecar.

A new fin design for the heads and cylinders helps reduce engine noise.

In addition to improving performance characteristics, attention was paid to increasing engine reliability: the wear resistance of the piston rings was increased, the crankcase sealing was improved, the kick-starter mechanism and the ratcheting mechanism at the clutch drum were improved. The flange fastening of the exhaust pipes to the cylinders provided better sealing of the joint and made it easier to separate these parts during repairs.

There have been numerous changes in the design and manufacturing technology of parts and components of the undercarriage. Among them are a steering wheel with an elastic mount, a two-cam front brake, and rear shock absorbers with an additional O-ring. A front mudguard with a stamped bracket and a saddle with an embossed pattern have been introduced, the padding of which connects to the base without rivets.

The electrical equipment of Jupiter-5 remained generally the same as that of the previous model, but the circuit and design of the devices were significantly improved. Thanks to this, engine starting has improved, the ignition system has become more reliable, and the battery is charged more stably. The best starting qualities even under unfavorable conditions - after driving with the lights on, with a weakly charged battery - have already been appreciated by the owners of the Jupiter-4 manufactured in 1984. They are achieved by increasing the sparking power due to the use of wire with an increased cross-section in the winding of the coil. A stable spark on the spark plug is provided at a voltage of 7.3-8 V when cold and 9.5-9.7 V when hot.

In order to reduce losses in electrical connections, the circuit for switching on the ignition coils and emergency engine shutdown has been changed. The coils are connected directly to the ignition switch; plug connectors are excluded from their circuit. The emergency switch has been removed from the circuit of coils, its circuit has been changed: it has become normally open, which better suits its purpose. If it is necessary to urgently stop the engine, the ignition circuit is no longer broken, but is shorted to ground by coil breakers. Of course, the emergency switch should only be used in extreme cases.

Another innovation is a button equipped with a strong spring to turn off a large part of electricity consumers and switching devices. It should be used in cases where the battery is almost completely discharged and starting the engine in the usual way is difficult or impossible. In such a situation, in order to start the engine, it is necessary, by pressing a button, to connect directly to the excitation windings of the generator any power source (even a flat battery from a flashlight).

The number of plug connections in the circuits for switching on the battery and the rectifier-voltage regulator BPV 14-10 has been reduced. This had a beneficial effect on the operation of the generator set and increased the stability of battery charging. The design of the BPV 14-10 block itself has also been changed: an additional (duplicate) terminal for the third phase of the generator has been introduced. Along with other improvements to the block's design and parameters, this measure also helped to increase its reliability.

IZH-Jupiter-5 uses improved switches for direction indicators and lighting (“day-night”). Their contact groups have become stronger, and the mechanism itself more clearly fixes the given position.

The new motorcycle will have an all-terrain configuration. It includes a sprung front guard, a spare wheel installed between the machine and the side trailer, which has an all-terrain tire (with increased lugs). To ride on dirt roads or even just before a difficult area, the motorcyclist can mount it instead of the standard drive wheel. This option will be appreciated primarily by rural workers. It is also convenient for tourism lovers, hunters, and mushroom pickers. The universal side trailer of a new design, developed for IZH-Jupiter-5K by the Vyatka-Polyansky Machine-Building Plant, is primarily designed for this circle of consumers. It can be quickly converted from passenger to cargo, designed for 120 kg. The hinged hood and trunk lid make the trailer more convenient.

M. PEREPELITSA, engineer at Izhmash, Izhevsk

Advantages and disadvantages

Despite all the modernization, the Izh motorcycle has both advantages and weaknesses. Powerful even by modern standards, it is clumsy, not very reliable, and requires constant attention. However, first things first.

Advantages

Power . It is enough for a comfortable ride even today.
Possibility to buy Izh Jupiter 5 with a cradle .
Low price of used motorcycles on the secondary market.
Maintainability and affordable cost of spare parts.
Moderate dimensions - length, width, saddle height.

Flaws

High fuel consumption , up to 6 liters per 100 km. And the fuel needs to be mixed with 2 tons of oil, which is inconvenient to do at a gas station.
Motorcycle weight . It is felt, especially when maneuvering at low speeds.
Low reliability of some components. In particular, problems with the gearbox are common.

Motorcycle design

But structurally the motorcycles of these modifications did not differ from each other.
All components of the motorcycle were mounted on a tubular frame. To provide suspension for the rear wheel, there was a subframe at the rear of the frame, attached to the frame by a non-rigid bolt connection. A power unit with a gearbox and a steering column equipped with a telescopic fork were installed on the front part of the frame. The fuel tank was located above the engine, and in front of it was the steering wheel, dashboard and headlight.

Behind the tank, the entire upper part of the motorcycle was allocated under the seat, with a rear fender with a brake light attached to it. Below the seat there were two glove compartments. The left one was for the battery, and the right one was for tools.

The rear wheel was installed on the existing subframe. To provide its suspension, the subframe, in addition to the non-rigid bolted fastening, was connected to the frame by means of spring-loaded oil shock absorbers. The springs had three-position adjustment, which provided a change in the rigidity of the rear suspension. The rear wheel was driven by a chain drive.

Exhaust pipes extending from the engine stretched along the entire motorcycle. To protect the driver and passenger from possible burns, the pipes were attached under the running boards.

The motorcycle was equipped with two-cam drum brakes with mechanical drive on both wheels. Subsequently, some versions were equipped with hydraulic front disc brakes.

Owner reviews

I bought my Izh U5 new from a store in 2004, drove it for five years, but had less than 10 thousand miles on it. Then the mot collected dust in the garage for four years, then he gave it to his son so he could study. Izhak started up after a long stay without problems, after replacing the battery and fluids. The technology is primitive, but tenacious; if only I had spare parts, this motorcycle will outlive me. Arseny, Novosibirsk.

An excellent option for the village, you can buy it alive for 10-15k, the tank lasts a long time, anyone can eat gasoline. There are a lot of minor breakdowns, but everything can be repaired easily. The Izh engine is high-torque and gets out of the mud on its own if the tires are suitable. My pepelats is generally ancient, a transitional model, but there are minimal differences even from the most recently released Jupiters. The spare parts all fit; if they don’t fit, they are filed and fit. Alexander, Usolye-Sibirskoe.

I bought my Jupiter5 back in 1990, the old man is still alive, periodically takes me around the dacha when I don’t want to drive the car on dead roads - I feel sorry for the suspension. Spare parts cost a penny, but something breaks every week))) And so the Jup is a normal moto for its time, the performance characteristics correspond to the price and years of development. Sergey, Syktyvkar.

Video

The video below shows a test drive of the motorcycle in the field, both on a dirt road and on asphalt. The motorcycle is specifically designed for off-road travel; under such conditions, this motorcycle can be a worthy competitor to foreign brands.

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Comments (6)

Vitaly:
02/27/2015 at 17:49
A Soviet motorcycle that has remained virtually unchanged over the years. It still has valveless primitive injection. You shouldn't expect much from him. Small motor lifespan. Always painful.
Answer
Zolotoiy:
02/28/2015 at 11:09
Of all the motorcycles that I have had, and there were quite a few of them, IZH U5 is a song 25 horses, semi-automatic box, playful, powerful, but like a parody dog, it requires care, who will say it’s rash, you need to keep an eye on it, that’s all, and I recommend it to everyone
Answer
sergmayorov:
03/02/2015 at 12:46
My friends, IZH U5 is still in my garage and drives steadily. Of all the Soviet-era motorcycles, this is the best. It lends itself to any tuning, the power is enough, the clutch is eternal. By the way, it holds the road better than a Java, since it is heavier. The spare parts are all domestic and cost a penny. However, the chances of crashing in this way are much less than in Japanese.
Answer
Jahanger:
05/15/2015 at 20:20
My friends, IZH Yu5 is still in my garage and drives steadily. Of all the Soviet-era motorcycles, this is the best. It lends itself to any tuning; the power is enough to last forever.
Answer
Vitaly:
07/04/2015 at 20:00
I have an Izh Jupiter 5 in my garage and it works like a watch, although it is 26 years old and its maximum speed is not 125 km per hour, but 160 km per hour, you just need to put 275 jets and a 21 sprocket on the chain, it will actually eat more.
Answer
allvolley.ru:
08/17/2016 at 11:03
There is still such a device! And the condition is excellent, and quite nimble)
Answer

Conclusion

Izh Jupiter 5 was structurally and morally outdated even before production began, but it still remains in demand in remote regions, where survivability and maintainability are valued rather than design. And as a first motorcycle , because it is capable of teaching both how to ride and how to repair your steel horse.

Specifications

Maximum engine power:	24 HP
Torque:	34 Nm
Working volume:	347.6 cm3
Motor type (cylinder arrangement, number of strokes):	two-stroke, two-cylinder
Number of cylinders:	2
Number of valves:
Intake type (Injector / Carburetor):
Bore and stroke:
Starting system (Electric starter, kick starter):
Maximum speed in km/h:	125 km/h
Cooling system:	Air cooling
Transmission (gearbox):	4-speed, manual
Clutch (Dry / Wet):
Drive unit:	Chain
Frame:	Steel
Chassis
Suspension (front/rear travel):
Brakes (Front/Rear):
Wheels / Tires / Rubber:
Dimensions and weight
Dimensions (Length / Width):
Seat height:
Ground clearance:
Curb weight:
Wheelbase:	1450 mm
Weight:	160 kg
Battery capacity:
Year of release:
Country of Origin:

Maintenance and repair work

Considering the fact that the equipment has long been discontinued, parts on the market are not difficult to find, since the motorcycle remains in use. Fortunately for many owners, the design of the Izh Jupiter 5 motorcycle is simple, so repairs will not be difficult.

To determine the degree of clutch malfunction, you must first check to what extent the crankshaft sprockets coincide with the plane of the clutch drum. If there are discrepancies, the Izh Jupiter 5 clutch is easily adjusted. It is necessary to bring it to 0.4 mm using washers installed on the input shaft between the spacer sleeve and the ring inside with bearings. The motor chain should not sag by more than 2 mm; if this happens, it means that the sprockets need to be replaced with others whose diameter will be greater than the circumference of the cavities in the gear.

In terms of technical characteristics, the model demonstrates good performance
When adjusting the clutch, you must carefully ensure that the spring nuts extend slightly beyond the edges of the caps by 4 mm, while the pressure plate must move without distortion. Adjustment of the clutch mechanism occurs after installing the right cover and the automatic clutch, after which the adjustment screw on the pressure plate is tightened, unscrewed by ¼-½ turn and the screw is fixed. The clutch lever is adjustable to a free play of 5-10 mm.
It is important to be able to adjust the idle speed of the crankshaft. You should act in stages. First, it is checked whether the throttle has free play and the engine is warmed up. The check can be done by setting low, stable speeds, rotating the throttle screw until the speed increases and then decreases. If the engine stalls when you open the throttle, you should enrich the fuel mixture and tighten the screw, and if it stalls when you close it, you need to unscrew the screw slightly. This procedure is considered the best for checking the carburetor, especially if you have to travel on a poor-quality road or the temperature conditions change. Preventative maintenance of the carburetor involves cleaning and flushing parts after 5,000 km.
Sooner or later the kickstarter wears out and engagement fails. To restore it, you need to weld the leading edge, this can be done at home if you have an electric sharpener. For convenient work, you should remove the ratchet from the clutch drum. There is no need to try to ensure the original shape of the teeth; it will be enough to achieve good engagement with an angle of 20-30°.

It is not difficult to find motorcycle parts on the market
When checking the clutch of the Izh Jupiter 5 motorcycle, you should pay attention to the wear of the discs; they may burst or become deformed. If the owner notices that the disc is swaying from side to side, then most likely it is bent. Sometimes there may be no obvious deformation, then you need to pay attention to the protrusions of the working surface. The repair consists of replacing the clutch discs.
Motorcycle repair includes ignition installation. You can install the ignition of Izh Jupiter 5 as follows: turn the crankshaft clockwise using the generator armature bolt, do this until the contacts open. Afterwards the screw is loosened and a small gap between the contacts is fixed. An ignition bushing is installed in place of the spark plug. It is important to align the extreme notch on the collar with the sleeve and end. Three screws are unscrewed until the contacts open, then two screws are fastened. The same must be done with the second cylinder.