How much oil is needed for 1 liter of gasoline for a Minsk motorcycle?

Minsk is a family of Belarusian motorcycles, which also includes scooters, ATVs and snowmobiles. The first version of the motorcycle under the Minsk brand went into production in 1951. In 2022, the company became private property. Over the years of production, more than 6.5 million motorcycles have been sold. The first model was designated M1A. it was originally released in Moscow. This motorcycle is based on the chassis of the DKW RT 125 model, the drawings of which were transferred to the USSR as war reparations.

Let's start tuning a Minsk motorcycle with our own hands

To increase power we will tune the engine, clutch, ignition system, cooling and exhaust.

Engine tuning in Minsk - adding a few horses

The most powerful engine in the base, as mentioned above, is a maximum of 13 horses. Of course, this is completely insufficient for modern dynamic riding, motocross, and stunt riding (depending on what the motorcycle tuning is for). Modifying the Minsk engine is not very difficult. To increase power, you will have to work on the cylinder and piston of the motorcycle engine. We reduce the combustion chamber by grinding. This increases the compression ratio and engine power. The engine is now suitable for using high-octane gasoline and this will have a positive effect on increasing power.

Reworking the ignition system

The standard ignition system with a very powerful and reliable generator, a contactless ignition system and an electronic switch require modification in terms of additional installation of a device to change the degree of ignition angle advance depending on the engine speed. With the help of such tuning, the Minsk motorcycle engine will run more smoothly and quietly, and its service life will increase significantly.

Motorcycle tuning Minsk

Exhaust tuning for a Minsk motorcycle

How to make a Minsk motorcycle quieter? To improve the power performance of this engine, it is very important to install a resonator in the exhaust system. A resonator is an oscillatory system where vibration energy is accumulated due to resonance with the driving force. A properly selected resonator allows you to ensure that some of the lost working mixture is returned to the cylinder by the time the exhaust window is closed. It is very difficult to find such a device for free sale, because... it was produced in limited quantities and only for cross-country versions of the Minsk motorcycle. But you can make it yourself using drawings available on the Internet.

Tuning the exhaust system on a motorcycle Minsk

Motorcycle tuning Minsk

Cooling system tuning

Increased power as a result of engine tuning will require a more efficient cooling system. It is necessary to purchase and install a more serious radiator.

Clutch modification in Minsk

Now, after engine tuning, the standard clutch will not be able to cope with the increased power in all operating modes of the motorcycle engine. It needs to be improved by replacing springs and discs. It is necessary to cut off a few millimeters of steel from the standard clutch discs and insert three more selected discs into the free space. As a result of this replacement, the clutch will become slightly stiffer in first gear, but overall the motorcycle will gain more dynamics and drive.

Now we can replace the rear wheel sprocket with a similar one, but with fewer teeth, which will add dynamics to the acceleration of the motorcycle. We replace the standard brakes with good disc brakes - do not forget about driving safety. All these measures, if carried out correctly and responsibly, will allow you to increase the power of a 125 cc motorcycle engine from the standard 13 to 20-23 horsepower, which of course will make your iron horse much faster and more interesting. A technically savvy owner can do the tuning of a Minsk motorcycle engine on his own, or you can contact a motorcycle center, where all the necessary work will be carried out not only quickly and efficiently, but also where you can quickly purchase all the parts and elements necessary for tuning a motorcycle.

Exhaust system

This element must be modified if the engine has been tuned. The problem arises due to the fact that the standard muffler is not designed for increased exhaust gas pressure.

As a result, in certain operating modes, the motorcycle engine begins to choke. Optimal mufflers were installed on a motocross motorcycle, but it is now almost impossible to purchase such a part. Such versions have not been produced for more than 20 years, and therefore spare parts for them have not been produced either.

You can make a high-quality muffler yourself. To understand how to make it yourself, let's look at how it works. Using a muffler of a certain shape allows you to create reverse draft. It allows the remaining combustible mixture to be sucked into the engine. A resonator is used for this.

You can make this detail yourself. On the Internet you can find a large number of formulas by which calculations are made. It is important to remember the basic rule here - the size of the resonator directly depends on the power of the motor. This kind of motorcycle tuning in Minsk allows you to achieve maximum efficiency and engine response.

Engine tuning

Probably every motorcyclist is a fan of dynamic riding, but the Minsk motorcycle is not particularly designed for this. Therefore, first of all, owners strive to modify the engine. You can easily add a couple of horsepower here.

Typically, cylinder boring is used for this. This way you can increase the compression ratio, and, accordingly, the engine power. Let's take a closer look at how this is done:

The block is ground down by 1.5 mm, the lower edge of the block head is also ground down, also by 3 mm. The motorcycle cylinder is being modified on a lathe;
Increase the size of the outlet and inlet openings;
Install new valves, better than those made in Japan;
The piston is being modified. They take a standard piston and fit it to the modified engine. If you do not have a special lathe, or you are not entirely confident in your abilities, then it is better to give the engine to an experienced lathe.

After such processing, the engine will receive an additional 1-2 hp. But, it is worth considering that it will be more demanding on nutrition; here it needs to fill with gasoline with an octane number of at least 92.

Appearance tuning Minsk

Every Minsk 125 owner has at least once thought about the appearance of his motorcycle. Perhaps we should start by repainting the frame and other parts of the motorcycle. The first thing to do is remove the handlebars, seat, tank, engine, wheels, fork and other parts to leave a bare frame. Sandblast the parts to be repainted or remove the old paint layer using special attachments for an angle grinder/drill. An attachment on a drill for an emery wheel with Velcro is also very effective for this. Be sure to get rid of pockets of corrosion. The next stage is puttying. This is necessary to get rid of deep scratches and level the surface. Parts with a leveled surface are degreased to prepare for priming. Apply primer in 2 layers. The dried soil should be sanded with 400 grit sandpaper. Then we paint it in the color we like in 2-3 layers, followed by a layer of varnish in 3 layers. The metallic color on your Minsk 125 motorcycle will look very impressive.

The next method of tuning Minsk is polishing the engine crankcase to a mirror finish. This procedure can also be done with your own hands using a set of sandpaper with grit from 120-180 to 2500. By sanding the surface of the engine in steps from coarse to finer, you will achieve an ideal matte surface. At the end of this work, use GOI paste, a felt circle and a drill to achieve the final mirror surface. The Minsk motorcycle engine will immediately be transformed!

This procedure applies to the rims, spokes and muffler - this will help them shine in a new way.

New road tires would be a good investment. The new tread pattern is not only effective when driving on wet asphalt, but also looks attractive. Replacing lighting equipment will also appeal to everyone. For example, LED turn signals and brake lights will not only give a modern appearance, but will also reduce the load on the generator, and will also increase road safety when driving at night. Separately, it is worth noting the efficiency of xenon installation. The recommended heat of light is 4300k as it is the most neutral white light, does not cause eye fatigue and provides the best illumination. A useful tuning in Minsk will be the installation of new chrome mirrors, which will also significantly increase riding safety and complement the transformation of the motorcycle. In conclusion, I would like to note that these tuning actions can be carried out selectively at will and combined according to your taste and financial capabilities.

Minsk was perhaps the most widespread and accessible of the motorcycles of the Soviet Union. Produced at the Minsk plant, it enjoyed deserved popularity among motorsports enthusiasts and ordinary citizens for its low price, ease of operation and good maintainability. This unpretentious motorcycle could serve as both the first vehicle for a novice motorcyclist and a workhorse for many residents of cities and rural areas.

The ancestor of the Minsk motorcycle was the motorcycle of the German DKW center, the equipment for the production of which was exported from Germany as reparations in 1945. The production of the first models was established in Moscow, but then by 1951 production facilities were transferred to Minsk. The first motorcycle rolled off the assembly line of the Minsk Motorcycle and Bicycle Plant back in 1951. For more than 60 years of production of motorcycles of this brand, more than 6.5 million Minsk motorcycles have been sold worldwide.

Tuned motorcycle Minsk 125

But this mass-produced motorcycle, like any other equipment, of course, has its certain drawbacks. The main ones include:

The rather weak engine is the most powerful available in the basic version, only 13 hp.
A poorly designed clutch that can slip even after the motorcycle has been driven for a long time.
On early models, the arrangement of the crankshaft bearings was poorly thought out.
Weak braking system.

But this amazing motorcycle provides its enthusiastic owners with ample opportunities to implement tuning ideas. And, although in the basic version, even with the most powerful engine, the Minsk motorcycle could hardly accelerate to 100 km/h, as a result of competently and responsibly carried out tuning from this beloved, but still not very technically advanced product of the Minsk plant, it is possible to make a truly nimble, responsive and fast motorcycle, not much inferior to its expensive foreign counterparts.

Motorcycle styling Minsk 125

Boosting a motorcycle engine Minsk – Soviet motorcycles

The engine needs to be disassembled. The following work should be done with the engine crankcase: insert and securely fasten the rings into both halves of the crankcase, reducing the diameter of the crank chamber to 121 mm, change the seals so that they can withstand a pressure in the crank chamber of at least 0.8 kg/cm2. In the engine cylinder, set the phases: exhaust - 164°, purge - 108° and intake - 128° (Fig. 66).

Increase the compression ratio to e = 9.5. Install a K-36 I carburetor with a diffuser diameter of 27 mm, the main jet must have a flow rate of at least 250 cm3/min. The purge windows in the piston should be cut to 25 mm (Fig. 67) so that they coincide with the purge windows in the engine cylinder.

To increase the effect of supercharging, the total length of the intake pipe should be 300 mm (the length of the intake pipe from the cylinder mirror to the carburetor is 100 mm; the length of the pipe with an internal diameter of 40 mm, between the carburetor and the air cleaner is 150 mm (Fig. 68). Ignition from the G-416 generator works poorly due to interruptions at high speeds. For normal engine operation, it is recommended to install an M-24G magneto. Ignition timing is 2.2-2.5 mm before top dead center. Spark plug PAL-14-8 or BOSCH-260-280 .

In the crankshaft, the bronze separator of the lower head of the connecting rod should be replaced with another one, for example, duralumin (D-16T, V-95) or made of cyanidated steel (it is also possible from steel 45 without heat treatment) with subsequent silver-plated surfaces. After running-in and final adjustment, the engine develops a power of 12 hp. and has excellent pickup.

Uprated engines for motocross M-105, M-106 and M2-125. Piston with two L-shaped rings and piston pin bosses shifted upward by 7 mm (compared to the standard size). The diameter of the crankshaft cheeks is 120 mm. The length of the connecting rod at centers is 125 mm. The length of the piston skirt is 62.5 mm, on the intake side the piston skirt is cut by 1 mm and is equal to 61.5 mm. Compression ratio e = 15.

Particular attention should be paid to the processing of the cylinder channels, their throughput and the correct angles of the purge exit (Fig. 69).

Head with an offset “jockey cap” sphere. Magneto ignition. Recommended ignition timing is 2.2-2.3 mm b.c.t. Candle PAL 14-15. Gasoline B-95, B-100. A-98. MS-20 oil in a ratio of 1:20. The engine is equipped with one carburetor with a diffuser diameter of 28 mm. The length of the pipe from the cylinder mirror to the center of the nozzle is 135 mm. The total length of the intake tract is 170 mm.

Be sure to install a large air filter (tank volume 2.5-3 liters) with paper filter elements. After all the work on boosting, running in and fine-tuning the engine, the maximum power is 14-15 hp. With. at n = 6600-6800 rpm. An engine like this can be increased to 20 hp. With. increasing the speed to 9000 rpm. But this will require a special crankshaft, piston, rings and higher valve timing, a new muffler and carburetor.

Flaws

First, let's figure out what shortcomings the motorcycle has, this will allow us to decide what needs to be improved first. In general, many problems are typical for domestic motorcycles, and when tuning sunrise 3m they are faced with the same problems.

The main disadvantages of the motorcycle are as follows:

Low-power engine. The most powerful engine is only 13 hp;
On the earliest models, the placement of the crankshaft bearings was unsuccessful;
Poorly designed clutch;
Weak brakes.

These are the main disadvantages of Minsk. In general, it is worth noting that all of the above can be eliminated with your own hands, significantly improving the performance of the motorcycle.