Tuning Izh Jupiter 5 - creating a modern appearance
So, let's start with the most interesting! As they say: you meet someone by their clothes... The factory appearance of the motorcycle has a rather dull appearance. If you like sports motorcycles, you will have to work hard to give new shapes to the motorcycle. The standard gas tank is ugly and also very heavy. This part of the bike immediately catches the eye, so we install a streamlined tank from a sports motorcycle. As a rule, there are plenty of these at showdowns. This detail is not only an external transformation, but will also improve the sense of control, because it allows the knees to better stay in the saddle. The bulky seat also needs to be replaced. This will have a positive effect on the weight of the motorcycle; the standard seat is very heavy.
You can make two-section new seats yourself:
- It is enough to cut out the base from a sheet of thick plastic and give it the intended shape.
- Cover with a thin layer of furniture foam rubber, then cover the seats with eco leather.
The next procedure will be to change the tail:
- First, cut out the desired tail shape from construction foam.
- Then use epoxy glue and fiberglass to cover the mold in layers.
- After the mold has dried, cut out the foam and remove the residue with a solvent.
The fiberglass tail lends itself well to priming and painting. Go for it! Well, the rear part of the frame will have to be welded to accommodate the new tail, depending on its shape and size. A good improvement would be replacing the old tires with road sports ones. Installing new mirrors will give a modern look, and most importantly improve visibility. The dashboard can be installed from a Chinese motorcycle or moped, as well as control panels on the steering wheel. It wouldn't hurt to install xenon in the headlight and replace all the bulbs, turn signals and brake lights with LED ones. Example Izh Jupiter 5 tuning photo:
Engine tuning Izh Jupiter 5
Many Jupiter owners are not satisfied with the power of their motorcycle. In this part of the article we will look at Jupiter 5 engine tuning. In fact, the Izha engine has great potential for increasing power. First, make sure that the engine is in more or less normal condition, the cylinder fins are intact, and the bearing seats in the crankcase are not broken. First of all, tuning of this model is to eliminate the “jambs” from the poor quality of production of parts of the serial industry of past years, since at that time they tried to reduce the cost of production as much as possible. Don't forget to clean the engine before disassembling. Having disassembled the engine, we advise you to replace all the bearings with European or Japanese analogues, because after tuning the Izh motorcycle, the speed will increase and the loads will increase. If the gaps between the pistons and the cylinder do not meet the standard, you will need to bore to the nearest repair size. Then we proceed to processing the purge channels. As a rule, these are steps at the joints between the bottom of the cylinder and the surface of the crankcase.
They create resistance and unnecessary swirl of the fuel mixture, which reduces the flow rate and prevents you from getting maximum power from the engine. This can be done using cutters and a drill.
After this, you need to smooth out any remaining unevenness with sandpaper. Also use sandpaper to sand the inlet and outlet channels in the cylinders, smoothing out any unevenness from the casting. Moreover, it is enough to process the inlet channel to a smooth rough surface, and the exhaust channel to the smoothest possible state for better movement of exhaust gases and to prevent carbon deposits. The bottom and surface of the pistons must similarly be polished to a shine. To increase the compression ratio, Jupiter cylinder heads need to be trimmed by 1.5-2mm to reduce the combustion chambers. This is done on a lathe, the heads are mounted in the chuck using mandrels. It is important to ensure the same surface treatment - the volume of both combustion chambers must be strictly the same. Increasing the compression ratio will entail a transition to 95th gasoline, and the ignition is set a few degrees earlier. It is highly recommended to replace the old contact ignition with an electronic one with automatic advance. It will allow you to achieve high speeds and spark at the right time. If desired, you can assemble the new ignition yourself. The crankshaft also needs to be modified. The standard crankshaft is too heavy and is designed to be ridden with a sidecar and a loaded motorcycle. You will have to unpress it, and grind the outer diameter of the cheeks to 125 mm in diameter, then polish the connecting rods to a mirror surface. The modified crankshaft is subject to assembly and mandatory balancing. This tuning of Izh Jupiter 5 will allow it to accelerate to 160 km/h.
Improvement of technical parameters
Tuning to increase power.
The design of the motorcycle engine allows for tuning to increase its power. One option is to re-press the engine crankshaft and change the support bearings. Usually, secondary shaft bearings from a Java motorcycle were installed as new bearings. This restoration made it possible to achieve an increase in engine power of the IZH Planet - 5 by 10-15%.
The next option for adding power was to increase the cylinder volume. For this purpose, its upper part was cut off and the sleeve was bored to 76 mm. Then the appropriate piston was installed, usually a piston from a Planet Sport motorcycle was used.
Increasing the speed of the motorcycle.
After this operation, the speed of the motorcycle increased, according to some sources, to 160 km per hour. Therefore, work to increase engine capacity was carried out by owners who planned to operate their vehicle mainly on highways.
The most difficult technical tuning option for adding power to the IZH Planet - 5 is the installation of supercharging. For this purpose, an exhaust valve is installed, the device of which corresponds to the analogues on the sports versions.
Then an exhaust resonator is installed, which has sharply directed parameters. Its task is to create a wave backpressure of the fuel mixture. Next, a spool valve is installed to obtain asymmetrical phases of engine operation, which avoids the direct release of the spent mixture.
Performing supercharging on the engine of the Fifth Planet is a rather complex process and therefore is not widely used.
Improved grip.
As engine power increases, it is necessary to carry out work to improve the clutch. Under standard conditions, the standard clutch works reliably.
But as the load increases, the risk of “burning” it and subsequent repairs increases sharply. The main steps for tuning the clutch come down to replacing standard discs with larger metal ones. Typically, such discs are made of two millimeter iron.
The use of thicker metal discs reduces slippage, warping, breakage and provides greater heat transfer.
Appearance tuning.
If external tuning of a motorcycle changes the design and makes it recognizable, then tuning the technical characteristics almost always reduces the resource of the power unit. Therefore, when starting to modify his motorcycle, the owner should always remember that modernization can bring not only benefits, but also harm.
Previous entry Motorcycle IZH Planet 5 and the characteristic features of the installed engine.
Next entry Elements and wiring diagram of Izh Planet 5, how to detect a malfunction
Refinement of the intake system
The intake system also applies to tuning the Izh Jupiter 5 engine. The main disadvantage of the intake system is the absence of a reed valve and the presence of only one carburetor on a standard engine. One carburetor does not allow you to develop high speeds and, accordingly, power. An excellent solution would be to install two identical carburetors together with two “house” reed valves.
To do this, you will need to make new inlet pipes for each cylinder separately with housings for reed valves. They ensure that the fuel mixture moves only inward, which has a positive effect on filling the cylinders and increasing power. Carburetors can be supplied from foreign 2-stroke equipment of similar volume, but if the budget is limited, then domestic K68 from the Ural motorcycle will do. In this case, it will be necessary to select jets for the engine size of the Izh Jupiter 5.
At the end of the article, I would like to note that tuning this model does not end with the methods outlined above. Tuning Izh Jupiter is a complex chain where one design change will entail another. Take care of strengthening the chassis, balance the motorcycle rims, strengthen the pendulum. The standard frame on this motorcycle is flimsy and requires reinforcement with stiffening ribs. It would be good if disc brakes were installed and the front fork was thicker. Tuning Izh Jupiter 5 is an exciting activity, and if you take this process seriously, the result can exceed expectations!
Tuning the Izh motorcycle. We are converting Izh to a 12V ignition system.
Despite the fact that it is already the 21st century, there are still many motorcycles left with a 6-volt ignition system.
A weak headlight makes driving in the dark completely unsafe. Spare parts for the 6-volt ignition system have not been produced for a long time. Finding a replacement for a failed generator or charge relay is almost impossible, although the motorcycle itself can still serve its owner well. To switch to 12 volts, you need to prepare the following things: a 12V battery, a 12V generator, a 12V charge relay, a piece of wiring from the generator to the charge relay from an Izh motorcycle with a 12-volt ignition system, ignition coils also need 12V, all the lights and turn relays can also be replaced with 12 V.
It is also necessary to make an adapter plate.
After all the necessary accessories are available, we begin dismantling the old generator and charge relay. We also change the ignition coils to 12 V. We install the adapter plate into the mounting points of the old generator on the right crankcase cover. We install a new anchor on the shaft. We attach the new generator to the adapter plate.
We install the new charge relay in place of the old one; if necessary, we alter the points at which the relay is attached to the motorcycle frame under the seat.
We connect the charge relay to the generator using a bundle of existing wires. We carefully isolate everything. We leave the wires from the contacts from the old wiring; we connect them to the negatives of the ignition coils. We connect a new battery, check the spark on the spark plugs by opening the contacts. We set the ignition timing as usual and start! We measure the voltage in the motorcycle network with a tester. With a correctly assembled circuit, the voltage in a running engine should be about 14 - 14.5V.
Now our motorcycle has the opportunity to install BSZ instead of contacts, which we could not afford before, but this is another topic. Good luck to everyone on the roads!
Dmitry Khoreshko
The editors of the magazine thank Dmitry Khoreshko for kindly providing materials for the article.
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