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The engine of IZH motorcycles is two-stroke, so the fuel combustion process is noisier than a four-stroke engine, and a larger amount of unburned gases is also released into the atmosphere. At the moment of release, the exhaust gases have a high temperature that is dangerous to the health of the motorcyclist. Therefore, the IL muffler pipes must have a more complex design. Comply with safety standards and not cause harm to human health and the environment.
The principle of operation of the muffler
After fuel combustion in a small chamber, the gases have enormous energy and escape at high speed from the cylinder pipe into the pipe and then into the muffler. This is accompanied by a lot of noise. After passing through the labyrinths of the silencer, the energy wastes its strength. This causes all exhaust parts to heat up. This system not only performs the work of removing gases. By selecting the size and geometry of the muffler pipe, you can achieve fuel savings and increase the power of a two-stroke engine. The picture of the layout shows which part is responsible for what.
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:
Causes of engine power loss
The first models of IZH motorcycles were equipped with easy-to-maintain mufflers. The advantage is complete disassembly. We began to notice a drop in power. First of all, pay attention to the exhaust system. Disassemble the muffler and give it a good cleaning. But soon they felt weak power again. Pay attention to the gap between acoustic filter 2 and partition 1. The lack of normal gap inhibits the exit of gases, which leads to a drop in power. The engine starts running intermittently.
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.
Muffler cleaning methods
The exhaust system has no adjustments, therefore, it is necessary to clean it in a timely manner.
Filters that dampen sound must be removed and burned. You can do it over a fire or use a blowtorch. Cool quickly using cold water. This leads to carbon deposits peeling off. Clean the pipe with a metal brush.
The next method is to burn off the carbon deposits and remaining fuel inside. Let's place the pipe vertically, you need to set it on fire from below, a draft will appear and all the carbon inside will burn out. All that remains is to remove the combustion residues.
A gentle way to clean. Use a chemical solution to soften deposits. The solution is prepared for a liter of water, 25 grams of caustic soda, 33 grams of carbonic soda, 8.5 grams of soap. Heat the solution strongly until almost boiling. Pour it inside the muffler and wait a couple of hours. After this, rinse thoroughly with warm water.
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!
Tags: homemade silencer Planet 5
Comments 29
and what about the sound, where is the video?!
yes there is no video, the sound is a little clearer than the original and louder)
no offense, but this guy's look is just terrible
Well, what if it’s already 20 years old, your friend wants to convert it into a chopper in the spring, I’ll help, post photos as soon as possible
so Kent and I collected from a pile of garbage! =)) we got into our hands a frame on wheels, a rusty tank and a motor in a bag without a cylinder and a shaft elbow =)))
Well, I was the first to watch it)
Damn, I’m wondering why and when I signed up for this amazing thing =)))
plus to my colleagues. The resonator at 2T is an important thing and needs to be calculated.
except for the appearance - natural stupidity. In old motorcycle magazines, I don’t remember the number, there was an article about calculating the resonator of a two-stroke bike, I advise you to look for this article.
on the 5th planet, the welded resonator should ideally be 1.5 meters long) but how to put it there is another question, so you shouldn’t touch it, it was a drain plug)
Yes, it's just a change in appearance and nothing more, my friend said I did it. I plan to bring the resonator to the top in Minsk like on a cross-country, we’ll think about it there!
there is no traction there, read the theory of a 2-stroke engine
I agree, a 2-stroke motor needs a tuned resonator, which is designed for a specific motor. Even the native P5 had more or less... What is the current consumption?)))
Making a resonator in real life 350 638
Dimensions of resonator parts designed for different speed ranges of the JAWA 638 motorcycle
Program for calculating resonators in Java, etc. download
1 way. A more labor-intensive method is to shorten the elbow according to its estimated length, and make the straight cone curved, dividing it into small cones. Photo of the resonator below:
How I decided to remove paint
It was necessary to have some kind of more or less durable grinder with an attachment made of Scotch Brite of suitable grain size, with Velcro on a cup with a rubber base. The surface would immediately be obtained without unnecessary scratches (although traces of metal molding and roughly cleaned welds previously hidden under paint would be visible).
Here, for example, are traces of metal molding:
Plus, the welds would have to be cleaned with a brush made of thin steel wires - also an angle grinder or a light high-speed reversible drill with such an attachment.
But instead of a so-so drill (and this is my drill in the photo and screws screws) with the money I had, I bought a semi-professional Skil grinder with a flexible shaft for 1390 rubles (790 rubles in the configuration without a flexible shaft; the flexible shaft resembles a speedometer cable in braid), I didn’t really use a single attachment from it. I asked him to sharpen an M6 bolt for a 3.2 mm collet, sawed it at the end and put small strips of sandpaper there.
This device made it possible to remove paint from the wheel rim without disassembling the wheel (without separating the rim and the wheel hub).
By the way, never clamp Chinese 3.0 mm bits with such a collet - they will turn and you will have to buy a whole set of collets (they are for different drills) in a radio parts store, which costs 200 rubles. Probably, the collet is 3.00 mm and not 3.20 mm and you need to clamp such attachments.
Included with the grinder was a pencil-shaped attachment made of diamond-coated steel. She was able to trim welds and draw on glass jars (the part with the largest diameter). These are sold in separate sets, but it’s still a shame to trim the metal with them.
You have to add machine oil to the flexible shaft of the grinder - in the place where it connects to the grinder, it then leaks out and ends up everywhere - on the floor, mask, face and clothes. It is better not to set the speed above positions 3, 4 or 5 during different operations set by the speed controller (there are 6 positions in total), since the motor in it starts to heat up too quickly at high speeds, the smell of insulation appears and you feel sorry for the sander.
Almost all the paint and rust was removed from the motorcycle with this sander. A grinder in addition to a grinder like this would be much faster, perhaps two or three days for all the parts including the frame. Some parts were cleaned by hand. It’s more pleasant to work by hand; there’s no rush like with a power tool. I would have done exactly this without a sander.
The best thing is a durable air compressor with sufficient liters per minute and air pressure capacity, and a few tools to go with it (a durable straight sander with easily replaceable bearings and a small angle sander with a rubber backing for Velcro). The rotation of the attachments in such tools simply stops and they do not get knocked out of your hands like a power tool - which often has a kilowatt of power to withstand possible overheating from prolonged use.
Correction of motorcycle appearance
Changing your appearance can happen in different ways. Among the most common:
- Fairing installation.
- Replacing the fuel tank.
- Seat modification.
- Motorcycle painting.
Fairing installation. This is the first thing that many lovers of modifying the appearance of motorcycles undertake. Although it is possible to cope with such a task, it should be recognized that the development of such components is a complex task that requires specific skills. The enterprises employ entire groups of specialists engaged in the design of fairings.
A person who does not have specific skills, despite all his talents, will most likely receive a result of dubious quality. The surface of the fairing will be uneven, which is clearly visible in the 5 photos posted online illustrating Jupiter tuning. The aerodynamics of the motorcycle may not improve, but worsen. Take all this into account before you decide to start making and installing a fairing.
Replacing the fuel tank is a completely justified decision. But you shouldn’t try to make a complex part yourself. This is not an easy task even for enterprises with special technological equipment. It’s smarter and easier to choose a ready-made fuel tank from some other motorcycle model.
Seat modification. You can try to make a change to the standard structure by upholstering it with a new material like leather or a good substitute, and installing a new filler. But the original seat has a significant mass. To reduce the weight of the motorcycle, it makes sense, as in the case of the fuel tank, to select a part from other equipment.
Painting IZ Jupiter-5 is a good thing. Here you can let your imagination run wild. But the best results can be achieved if you know the laws of color combinations or consult with a professional designer. Otherwise, instead of a stylish combination of contrasting colors, you can end up with an eye-catching color scheme.
If you are interested in long-lasting paintwork, first apply a layer of high-quality primer and refuse to use nitro paint, preferring alkyd or polyurethane enamels.
