Switches KET-1A, BKS 251.3734, BKS 261.3734, BKS 1MK211, BKS 70.3734, BKS 94.3434 designed to work with generators 26.3701 (6V 45W), G-427 (6V 65W), 43.3701 (12V 65W), 80.3701 (12V 90W), GM-02.02, GM-03.02, R71, 92.3702M-02.02, GM-03.02, R71, 92.3702.
The scheme works as follows. AC voltage generator with ignition windings L1 arrives at rectifier diode V1. Rectified voltage through the R6 V5 chain and ignition coil charges capacitor bank C2 C3. Some time after charging capacitor enters signal from the sensor generator L2 to the control electrode of thyristor V6. Thyristor V6 will close the battery of capacitors C2 C3, which will cause a sharp change in induction in the ignition coil and sparking on spark plug electrodes(voltage at secondary winding ignition reaches several dozens kilovolt). Current limiting resistor R6 and smoothing capacitor C1 are used to ignition winding current limitation L1 and smoother charging of the battery of capacitors C2 C3. Zener diodes V3 V4 provide voltage stabilization at the level of 150 V. Voltage stabilization is necessary so that the battery of capacitors C2 C3 and thyristor V6 do not fail due to overvoltage. Chain V2 R2 is necessary for rectifying and matching the signal from sensor L2 with the control electrode of thyristor V6. This switch has a number shortcomings and weaknesses:
- The maximum operating voltage of capacitors C2 C3 is 160 V, and since the voltage is stabilized by zener diodes V2 V4 at 150 V, the capacitors operate at the limit of their capabilities. Zener diodes of the D817 series have an error of 10%, so the risk of failure of capacitors C2 C3 is quite high.
- When the switch operates for a long time, resistance R6 becomes very hot. As a result, the soldering may melt or the resistor itself may burn out.
- The circuit between the generator sensor and the control electrode of thyristor V6 does not contain a filter against interference and interference, as well as overvoltage protection (stabilizer). Eventually - unstable work and the probability of failure of thyristor V6 at high speed.
- At high speeds engine capacity C2 C3 will not have time to charge - resistor R6 will limit capacitor charge current.
Switch diagram BKS 251.3734, BKS 261.3734 presented in the figure. 
All BKS switches contain two circuits: ignition and lighting. Scheme ignition is similar to the KET-1A switch, therefore it has the same flaws. The truth is in switches of later releases (since the late 80s) capacity C1 is 2.2 µF 250 V (as in 2MK211). Let's consider the principle of operation of the circuit lighting stabilizer. From the lighting winding of generator L3 AC voltage goes directly to pin 02 of the switch output (according to the diagram on the right). Thyristor V5 is closed. At the moment when the voltage of winding L3 exceeds the specified value ( 14 V or 7 V), thyristor V5 will open and short circuit winding L3 to ground. This will only happen with a positive half-cycle (relative to ground) at terminal 02. Thyristor control circuit works as follows: the alternating voltage is rectified by the diode bridge V9 and supplied to the voltage divider R2 R3 R4. The ratio of R2 and R3+R4 determines the division coefficient. Smoothing capacitor C3 ensures stable operation of the circuit. When the voltage in section R2 R3 exceeds a certain value, zener diode will open by applying voltage thyristor control electrode. For 12 V lighting circuits Zener diode V7 D814A(opening threshold 7.7 V), and for 6 V respectively KS147A(opening threshold 4.7 V). The zener diodes are selected in such a way that the voltage at the control electrode does not exceed 3 volt, otherwise the thyristor will quickly fail. Therefore, when switch rework For a different voltage it is necessary to replace the zener diode. By selecting resistor R3 adjustment voltage at the switch output. The advantage of the circuit is that the voltage from winding L3 does not decrease when thyristor V5 is closed, since it is connected in parallel with the lighting winding. This is important when the engine is running idle speed .
Switch BKS94.3734 designed to work with generators GM-02.02, GM-03.02, R71, 92.3702. The main feature of the switch is the absence of sparking when generator reverse. Chain V2 R5 VT1 shunts the signal from sensor L2 when the rotor rotates in the opposite direction and in the presence of a false signal ( sensors located inside generator). 
Block BKS 70.3734 predecessor of the Kovrov 2MK211. The blocks are designed for generators with internal sensor and are practically no different. Below are BKS 1MK211 switch diagrams And BKS 70.3734.
Device block BKS 70.3734 and PCB topology.
Ignition circuit slightly different from KET-1A. The above shortcomings have been eliminated. The sensor circuit contains rectifier V6, filter R1 C4 C5, as well as Voltage regulator R1 V3. Such a switch is more resistant to interference and interference in the sensor circuit. However for forced engines it won't fit. The lighting circuit of the switch is similar to BKS 261.3734.
How to increase (the lamps shine dimly) or lower (the lamps burn out) the voltage from the switch. If we are not talking about converting 6V to 12V or vice versa, then it is necessary to select resistance R3. First you need to open the switch case, namely remove polyurethane foam . The process is quite tedious and can take 30-40 minutes. This is easier to do if you preheat the case - pour boiling water over it from a kettle or place it in a warm place (for example, on a radiator). Next you need to find resistor R3 (it is highlighted in red in the photo).
Please note that this resistor soldered on top to the board. Unsolder this resistor and solder a variable resistor (rheostat) with a nominal value of 200...1000 Ohm with wires 20...30 cm. Then install motorcycle switch and start it. When adjusting the variable resistor, find its optimal position - the light in the headlight should not flicker at idle engine speeds and should not burn too brightly at high speeds ( lamps burn out) . After adjustment, measure the resistance multimeter and select the resistor value. If the value is not a multiple of the nominal values, you can take several resistors and turn them on daisy chain(resistances are summed up). Solder the resistances and fill the case with foam.
How to convert a 6V switch to 12V and vice versa. For this modification, you will need to completely clean the case of foam and remove the board. 
Remove the foam from the back of the board.
Replace Zener diode V7: for 12 V circuit D814A(any 7...9 V zener diode will do), but for 6 V KS147A(any 4…5 V zener diode will do). In the photo, the D814A-1 zener diode is highlighted in red.
Next, you need to carry out all the operations to select resistance R3 (see above). If desired, you can solder in a variable resistor instead of R3 and bring out the movable part of the resistance handle in order to immediately fill the switch with foam and make adjustments “on site”.
THE BEAST NAMED ABRIS
Ever since the times of Tsar Gorokh (or more precisely, since the early 60s), Kovrov motorcycles began to be equipped with generators alternating current. At first it was G-38, later G-401, G-411, G-421. They were distinguished by the fact that they were extremely simple - no ever-running battery, no capricious brush assembly. In addition, the rotor, which is a permanent magnet, is as reliable as a sledgehammer. But, as you know, every barrel of honey comes with a fly in the ointment. Here it was a contact ignition system, in which, in addition to the traditional adjustments of the ignition timing (by turning the generator housing) and the gap in the cams, it was also necessary to “catch” the outline. What kind of beast this was, few people knew, and more than one generation of motorcyclists of the 70s strengthened their muscles by pushing devices that did not want to start at any cost. In addition, such generators had three separate light windings that powered the circuits of everything at once - headlights, brake lights, and flashers. And this increased the likelihood of a short circuit.
A quiet revolution occurred when the G-427 generator, which did not have breaker contacts, was installed on Voskhod-2M (1976). On the rotor, instead of a cam, there is an additional magnet that induces an electric current in the winding of a special sensor. The pulse of this current (output through the terminal marked “D” - “sensor”) was the master in the circuit of the thyristor located in the KET-1A switch. The energy required for sparking was generated by two special coils connected in series, located on the stator (the output was marked with the letter “3” - “ignition”). Adjusting the system was reduced to setting a gap (0.3±0.05 mm) between the magnet rotor and the sensor core plates.
THE SHINE AND POVERTY OF "CONTACTLESS"
The weak point of the first “contactless” generators is the sensors. The vibration caused the fastening screws to loosen and the gap to “go away”. If the sensor came into direct contact with the rotor, interruptions occurred in the motor. By the way, broken crankshaft main bearings can also cause contact with the rotor sensor and, as a result, incomprehensible interruptions in engine operation. In the sensors, the wire in the turns often broke, and the solder terminals fell off. Almost all of these shortcomings were eliminated only in the new generation of generators 2MK-208 (80.3701). They began to be installed on the Voskhod ZM-01, and later on all Kovrov motorcycle products (except for the Pilot and Ptakhi). In them, the sensor winding is located together with other windings inside the stator, and in the block electronic ignition a voltage stabilizer was introduced (hence the abbreviation BKS - switching-stabilization unit). The Pilot has a flywheel type generator, that is, the stator windings are located inside a rotating bell-shaped rotor. The bobbin and switch-stabilizer are the same as on motorcycles.
The only adjustment of modern Kovrov generators - ignition timing - is made as on old models - by turning their housing. If the engine runs “hard”, the starter lever pushes against the leg when starting, which means the ignition is too early. Turning the stator clockwise (after loosening the three screws) will eliminate the unwanted effect. “Sluggish” operation of the engine and overheating that occurs in it indicate that the ignition is late. You can set the ignition timing absolutely accurately using a car strobe light. The only inconvenience that arises is that it will have to be powered from an external source. direct current. When the optimal ignition timing mode is reached, a rotor rib with a circular mark appears in the window of the stator housing. For "Pilot" - the risks on the rotor and stator must match.
"AP-GRADE" IN KOVROVSKY
Why our people love the “Soviet” motorcycle industry is for the scrap interchangeability of parts of its various products. Thus, new “contactless devices” can be installed on previous models Kovrov motorcycles - the landing dimensions and dimensions allow this to be done. Condition - the electrical circuit needs to be modified: connect the CET or BCS. Increased spark energy will require another bobbin - B300B, interchangeable according to seats with the previously used B300. (By the way, the old and new bobbins are no different in appearance. However, numerous attempts not to change the old unit sooner or later ended with the windings burning out!) Fans of “upgrades,” that is, increasing the performance of electrical systems, can be advised to install a bobbin manufactured in . Sarapule, from "Izha" (designation: 7.109-37.05.010). Its use increases the spark pulse duration by approximately 15% and its energy by 60%. As a result, starting the engine is noticeably easier. By the way, the reverse procedure - installing a Kovrov reel on an Izh with a contact ignition system does not give anything good. The reel overheats and very soon runs out.
The transition from KETs to BKS (with the advent of the new generator 43.3701 on Voskhod-ZM) marked the advent of the era of 12-volt electrical equipment. The headlights have become not only brighter, but also more stable. Supports constant pressure stabilizer built into the BCS. However, owners of new 12-volt generators can, if necessary, connect the KET-1A unit for operation. It is connected to the wiring terminals according to the letter designations (see diagram). But the lighting devices in this case will not “want” to work. To “want”, you should install a regular BCS. Owners of old motorcycles are luckier: instead of KET, they can safely install BKS. Their ignition circuit, as before, will be 6-volt (since the generator has not been changed), in which voltage stability is maintained (by the way, rather mediocrely) by a special DR100 choke located in the tool box.
SEEK AND YOU WILL FIND
Although modern system The ignition of Kovrov motorcycles is quite reliable, and it can fail. Before delving into the elements of the system, check for breakdown of the spark without a spark plug cap - set a gap of 6-7 mm between the high-voltage wire and the ground of the cylinder head. If there is no spark, begin to search for it more methodically. You probably did not connect the plug connectors tightly. Poor contact of the base of the BCS housing with ground does not have any effect on the operation of the system - ground is output by a separate wire. But in old KETs, the “mass” was brought out to the body, and its contact with the frame is necessary.
The generator itself, both “owl” and “pilot”, fails extremely rarely. To check its performance, you need a tester with an ohmmeter function. So, the resistance of the charging windings (red wire and body, or terminals “3” and “M”) should be within 400 Ohms; the resistance of the sensor windings (black and pink wire, or terminals “D” and “M”) is 40 Ohms. The winding resistance of the lighting circuit (purple wire and housing) should be 0.4 Ohm.
All resistance measurements are carried out on the sockets of the generator harness connector disconnected from the BCS. Old generators with KETs are checked in the same way. Instead of resistance, you can measure the magnitude of AC voltage. On the charging windings, when cranking the crankshaft with a kick, it is approximately 50 V, on the sensor windings - about 2 V. The specific voltage value depends on how sharply the kickstarter lever is pressed.
The rotors of Kovrov motorcycles are an eternal part. But problems may arise with “pilot” cars from early years of production. The fact is that their magnets were glued to the rotor with an epoxy composition, and over time, the magnets often broke out of the housing under the influence of centrifugal forces. The rotors of modern Pilots do not have these shortcomings.
The bobbin (high-voltage transformer 2102.3705, 1480026900001) is also checked using an ohmmeter with the wires disconnected. The resistance of the primary circuit should be within 0.4 Ohms, the secondary circuit - 6.7 KOhms.
But even if the winding resistance is normal, and a spark jumps when you press the kick, the unit may still be faulty. It happens that the motorcycle starts, but when the speed increases, interruptions begin and the engine stalls. This is a consequence of broken contact inside the housing. Therefore, the only reliable diagnostic method should be replacement with a known good part. Ideally, you should take it with you" gentleman's set" - high voltage wire with cap, reel and BCS. By connecting these nodes in series, the fault can be quickly identified.
Unfortunately, neither the reel nor the commutator can be repaired, since they have non-separable housings. Take this advice: once you have verified that a part is faulty, throw it away immediately.
UNIQUE DIVERSITY
The ignition systems described above were equipped not only with motorcycles from the V.A. Kovrov plant. Degtyareva. Generators G427 and KET1 were used by Minsk motor builders. The modern model of "Minsk" ("MMVZ 3.11311") has an original flywheel-type generator, but the BKS is completely identical to the Kovrov one. The place of its manufacture is the Republic of Belarus, the BATE plant. In Russia, electronic components are made in two places at once: in Kherson and Kovrov itself. These BCSs differ only in their brand mark; in terms of connecting connectors they are completely identical. However, there are still differences. But we'll talk about them another time.
ELECTRICAL EQUIPMENT FOR KOVROV MOTORCYCLES
| Motorcycle brand, year of production | Generator | Generator power, W | Switch | Spool | Voltage in the lighting circuit, V | Peculiarities |
| "Voskhod-2", 1972 | G-421 | 45 | - | B-300 | 7 | Mechanical contact ignition system |
| "Voskhod-2M", 1976 | G-427 | 60 | KET-1A | B-300B | 7 | Electronic contactless ignition system |
| "Voskhod-ZM", 1983 | 43.3701 | 65 | 261.3734 | 21.3705 | 14 | Transition to 1 2-volt electrical equipment, stabilizer and switch combined into one unit |
| "Voskhod-ZM-01", 1989, as well as "Owl", "Farmer", "ZiD-200" | 2MK-208 (80.3701) | 90 | BKS-1MK211 (70.3734) | 2102.3705 | 14 | The sensor winding is inserted inside the stator |
| "Pilot", 1995 | 190003090001 | 60 | BKS-1MK211 | 1480026900001 | 14 | Flywheel type generator |
| "Bird", 1998 | 164003090001 | 20 | BKT1 164 | - | 14 | Flywheel type generator, bobbin combined with commutator |
Old Minsk and Voskhod motorcycles used . They related only to ignition and had nothing to do with lighting. Modern motorcycle switches Minsk and Voskhod They additionally have voltage stabilizers, so they play a playing role in the entire electrical chain. In this article I will talk about the KET-1A switch for 6-volt motorcycles. But the very principle of operation ignition switch it’s the same everywhere, which means the article is worth reading for owners of modern motorcycles if they want to understand contactless system ignition
As already noted, the article contains several photographs. I found it on purpose switch circuits KET 1A and even took a photo of him inside. This will make the situation much clearer if someone doesn’t even know what they look like.
In one of the photos we see electronic circuit the ignition system and the circuit diagram and the switch itself. It is on the basis of this diagram that we will explain operating principle of KET-1A. And now to the point, we read very carefully and immediately compare everything said with the ignition circuit from the figure.
When it starts to spin crankshaft, let's say we press the kickstarter or simply take some moment while the engine is running, a current arises in coil 1. This current flows (alternating current) from terminal 3 to the input of the switch, enters diode D1 (the diode rectifies it into direct current), then passes through resistor R1 (this load resistor), enters diode D2 (here it is rectified again) and enters capacitor C2. The other end of the capacitor is connected to a high-voltage transformer, which means that the current in this case charges capacitor C2. The high-voltage transformer in this chain acts as a load, an ordinary resistor, or even simpler, an ordinary connecting wire. Having understood what has been said, we see that only the upper part of the diagram has been discussed by us. Now let's move on to other parts switch KET-1A. They can be divided into lower left and right, the left part has two diodes D4 and D5. These are zener diodes that perform the role of stabilization. They are designed for a voltage of 150 V. Thanks to them, voltage exceeding 150 V goes to ground through these zener diodes. They were introduced to stabilize the current so that too much current does not flow to the bobbin (high-voltage transformer), which can cause it to fail. Now the bottom right corner remains. Here we see a thyristor connected to ground and a capacitor, and diode D3 with resistor R2. Let me explain this part. What is a thyristor? This is an element similar to a diode, but it does not allow current to pass through until a certain point. In order for the thyristor to pass current, it is necessary to apply a certain signal to its third contact, the so-called “key”, its “gate”. When this signal arrives there, that is, a current of a certain structure, the thyristor will open and release voltage through itself. It was precisely thanks to the thyristor that it was possible to create a spark only at a certain moment. When the cylinder piston approaches TDC (top dead center), the thyristor switch KET-1A opens and we have a chain that already consists of a capacitor and a high-voltage transformer connected in parallel. What does it mean? The capacitor discharges and instantly supplies all its energy, that is, current, to the bobbin, and it, converting it into high voltage, supplies current to the spark plug. At this moment we have a spark. When the piston passes TDC, the signal to the “gate” of the thyristor disappears and it closes, immediately activating the circuit described above. That is, voltage comes from the generator again and capacitor C2 is charged again. The last details that almost nothing has been said about are the diode D3 and the resistor near it. They are designed so that only the required signal is sent to the thyristor “switch”, and not just any signal, otherwise it may accidentally open on similar signals, because the sensor constantly supplies a certain current.
And now the second part, without any introductions.
I have already said in popular scientific style how KET-1A works. I don’t know if it will be easier to describe everything, but I’ll try in case someone didn’t understand everything mentioned in the first part.
The switch has a capacitor, it is charged from the generator. The entire circuit is designed in such a way that the current does not flow to the bobbin itself directly from the generator. In order for the current to flow, it is necessary to make the capacitor C2 a kind of battery. This is done using a special electronic switch. This switch connects capacitor C2 to ground at the moment when a spark needs to be made. All this happens electronically, not mechanically. And when a spark should jump through the spark plug, this electronic toggle switch - a thyristor - supplies the other end of the capacitor to ground, it turns out that all the charge in it flows to the bobbin and, converted into high voltage, to the spark plug. A spark passes. Here's another way to explain the electronic ignition switch.
I really hope that I clearly explained the essence of the electronic ignition system and the circuit diagram of the switch KET 1A. I repeat, there is nothing complicated here if you understand at least at the school level in electrical engineering. If you wish, you can learn even more about ignition by looking for my old articles from last year. In some notes I talked a lot about ignition with contacts and with a switch. Read it, it's very valuable information.
Among the breakdowns in the switch there are different ones, now I’ll list them a little. Diodes, zener diodes, thyristors, and capacitor C2 may burn. These are the very first places to search. Resistors rarely burn out. Often there may be desoldering of contacts. Personally, I had three times when parts inside fell off over time. To doubt whether this is really the case with the switch or not, you can simply check by taking another switch and trying it. It is not difficult to remove this spare part, so a neighbor, and even more so a friend, can easily agree to help out. You can also try to check before this whether current is flowing into the switch itself. By placing our hands on the output of the generator at the KET, we feel the current by turning it slightly with the kickstarter. Don't be afraid, it won't hit you too hard unless you hit the kickstarter too hard.
From the photos provided, as I mentioned, you can see for yourself KET 1A and its structure, dimensions, internals. In conclusion, I would like to say that many motorists call the KET-1A a six-volt switch. It is not right! In the KET 1A switch only the ignition voltage passes, and about 150 volts. It is the new switches that have a network stabilizer and they can theoretically be called twelve-volt, although this is not entirely true. And yet, it is quite possible to use it for new motorcycles, the structure is the same, but the connections will not fit. In this case, lighting can be supplied through another switch (if only the ignition part has burned out, but the lighting part is working properly) or directly. In this case, the light will depend on the “gas” and the bulbs will light up at high levels. But you can connect without fear, the bobbins are the same, the voltages are also the same. Personally, I installed it myself Minsk 12 V and Voskhod 12 V such a switch (by the way, the one in the photo, I used it once) and everything worked quite well. Which is understandable, the principle of operation itself is completely identical.
Having convinced myself of the reliable operation of my creation, my colleagues decided to make a similar improvement to their motorcycle equipment. However, questions appeared like “I assembled it according to your scheme - explain why it doesn’t work for me.”
Here are some typical faults:
- no spark at all;
- the engine works well at idle, but fails at speeds above average;
- the engine starts well, but mainly one cylinder works, the second one picks up occasionally, the flashes follow unevenly;
- there is no spark only when installed in the Izh motorcycle circuit
- on the Voskhod motorcycle there is a spark, when replacing the switch-stabilizer unit (BKS) with a similar one of a different type (251.3734 on KET 1-A), the malfunction disappears.
All of the above troubles indicate a defect in the BCS. Let's look at the factory diagram of the block (Figure 2). It is copied from the KET 1-A block produced in the 1980s. In terms of switches, the VD2 zener diode is represented by the KS650 (or two D817Bs connected in series).
| Element designation on diagrams | KET-A | 251.3734 |
| C1 | MBM-1.0x250 V | MBM-1.0x250 V |
| C2, C3 | MBM-1.0x160 V | MBM-1.0x160 V |
| VD2 | 2xD817B | KS650A, KS680A |
| VD1, VD3, VD4 | KD105G | KD208B, KD2091 |
| VS1 | KU201I(M) | KU2211 |
| R2 | 100m | excluded |
The latest versions of BKS - 251.3734, 261.3734, 262.3734 are not schematically different. Only the appearance and type of some details have changed.
The operating principle of the devices is the same, capacitor C2 is charged from the high-voltage winding of the generator along the circuit VD1, C1, VD2, VD4, R2. With a positive voltage pulse from the transmitter, the thyristor VS1 opens through VD3, which discharges C2 onto the winding of the ignition coil TV1, forming a spark on the spark plug F1. Zener diode VD2 limits the voltage on C2-VS1 at 130-160 V. However, with the switch running, the voltmeter showed 194 V - an obvious overvoltage, the influence of the scatter in the zener diode parameters. I would like to note an interesting detail - two MBM type capacitors are used as C2. Such capacitors can operate in pulse mode for a long time. Being “self-healing”, they easily tolerate short-term overvoltages.
The breakdown areas of the plates are filled with paraffin impregnation of the dielectric. Unfortunately, this does not go unnoticed - over time, the foil of the coverings begins to resemble a sieve, and the capacity of the device decreases. Dielectric breakdowns lead to an increase in conductivity and the appearance of leaks. When working in a switch, such a capacitor simply does not have time to accumulate charge during the time between two sensor pulses. This is why the unit that normally works on the Voskhod (Minsk) motorcycle malfunctions in the circuit, where the frequency of the trigger pulses is twice as high.
A leaky capacitor is identified using a simple diagram (Figure 3). In compliance with safety measures (the circuit is galvanically connected to the household network), we connect the capacitor being tested into the circuit. The indicator lamp should not light up - the glow indicates the presence of a leak. Check time is 15-30 minutes (in doubtful cases - up to 1 hour). Despite the somewhat barbaric method of testing, it is practically safe for the capacitor. During operation, it is subjected to heavy loads. Thus, I identified thirteen capacitors with obvious leaks, four of them in blocks that worked normally on single-cylinder engines, but failed in the Izha circuit.
Replacing capacitors in KET-1A is not difficult - the unit can be easily disassembled. The same replacement performed by 252.3734 is more difficult. First, remove the porous mass filling the housing by boiling the switch in boiling water for 15-20 minutes. Then we carefully pluck out the filler with tweezers. By pulling the connectors, we remove the board and gain access to the printed circuit board. You can, of course, replace a faulty device with a similar one, but there is no guarantee that the new one will not fail soon either (see the reason above), so I recommend replacing it with capacitors like K73-17 1.0 μF/400 V (or even better, 4x0, 47 µF/630 V). Two capacitors are normally located on the board. We seal the block by filling it with construction foam or a rubber plate cut to size. I would warn you against using various auto sealants - their active components will eventually destroy the copper traces of the board. In order to ensure maximum reliability of the device, I consider metal-paper capacitors of the MBG, MBGP, MBGCh types (the letter G indicates the design of the device), designed for a voltage of 400-630 V, as a “no alternative” option. The only problem in this case is the dimensions. A compromise option is possible - in the circuit for the Izh-Jupiter motorcycle, we reduce the value of C2 to 1 µF. This will ensure its guaranteed charge in half a revolution of the crankshaft.
The remaining elements of the device usually do not cause any particular complaints. S1 (K73-15) is quite reliable. I advise you to replace diodes VD1, VD4 with KD226G (with a yellow ring). VD3 is practically unkillable. It happens that the VS1 thyristor changes its characteristics (the engine starts to start in the opposite direction) - this can be eliminated by replacing it with a KU202N or (even better) with a T122-20-10. It is extremely rare for KU221G (KU240A1) to fail. Replacing the SCR involves selecting the minimum control current. This ignition circuit is very demanding on this parameter. I carry out the selection using the scheme shown in Figure 4.
Moving the slider R1 from bottom to top, we note using the milliammeter PA1 the value of the opening current of the studied trinistor VS1 at the beginning of the glow of the lamp EL1. For use, we select specimens with control current I = 1-8 mA. Unfortunately, there are SCRs with increased leakage current. This parameter is checked according to the diagram shown in Figure 3. The glow of the lamp will indicate a malfunction of the device.
The BKS restored in this way is suitable for further use in the ignition system of both single- and two-cylinder motorcycles.
The electrical equipment of the Voskhod 2m motorcycle includes a G-427 generator, a KET-1 switch, a high-voltage transformer, a headlight, central and other switches
Generator G-427 alternating current with excitation from permanent magnet with an inductive sensor for the electronic ignition system. Eight coils are placed in the grooves of the stator, made of stamped electrical steel plates, which form four independent chains:
- power supply to the ignition storage capacitor;
- lighting and sound signal;
- direction indicators;
- brake signal.
Voltage regulation in the circuits of lighting loads is carried out according to the principle of parametric regulation, i.e. The winding data of the generator are selected in such a way that as the rotor speed increases, the voltage at the generator terminals changes within certain limits for a certain load. Attaching the generator stator to the engine crankcase provides adjustment of the ignition timing.
The following terminals are located on the generator stator cover:
- charging coils of the power supply circuit of the Voskhod ignition storage capacitor;
- direction indicators;
- brake signal;
- lighting;
- sensor.
Which are marked accordingly:<<З>>, <<У>>, <<Т>>, <<О>> and<<Д>>.
The sensor is mounted on the generator stator cover using screws.
The generator rotor with the sensor rotor located on it is mounted on the right axle axis of the engine crankshaft with a bolt and is secured against rotation by a key.
Caring for a sunrise motorcycle generator - how to remove, what to check and install correctly
Generator maintenance mainly comes down to tightening the threaded fasteners of the generator stator and rotor, as well as the wire terminals.
In order to remove the generator, you must:
- disconnect the wires of the ignition circuit, sensor, brake light and direction indicators from the generator terminals;
- unscrew the three screws securing the stator to the crankcase and remove the stator;
- Unscrew the bolt securing the generator rotor and, with light, careful blows of a wooden hammer on opposite sides of the rotor, remove it from the trunnion and remove the key.
Checking the removed parts
After removing the generator stator and rotor, wash the parts with clean gasoline and carefully inspect them. Disassemble the wire fastening terminals on the stator. Wipe dry all insulating parts of the terminals.
Generator installation
Installation is carried out in the reverse order, in this case it is necessary:
- check the runout of the generator rotor, which should be no more than 0.1 mm with the bolt secured;
- tighten the generator stator without distortions, ensuring a tight fit to all three supports;
- install the ignition correctly;
- The generator wires must be securely fastened and well insulated from each other.
Ignition adjustment Voskhod
The ignition timing is set by turning the generator stator after first loosening the three screws securing the stator to the crankcase. For normal engine operation, it is necessary that the moment of spark formation (on the generator, this moment is determined by the coincidence of the sensor rotor groove with the protrusion on the sensor coil frame. Fig.) coincides with the moment when the piston does not reach the top dead center of 2.5-3.0 mm (at running the engine on gasoline with an octane rating of 92).
The gap between the rotor and the core of the sensor coil should be within 0.3±0.05mm.
The gap should be set as follows:
- loosen the screws securing the sensor stator to the generator stator cover;
- By moving the sensor stator in the grooves of the generator stator cover, set the required gap, and then tighten the fastening screws.
Coil Voskhod - high-voltage transformer B-300B
The high voltage transformer is located under fuel tank and serves to convert current low voltage into current high voltage. The transformer consists of a core, primary and secondary windings, a housing and a cover with terminals. During operation it does not require maintenance and cannot be repaired.
The electronic switch KET-1 is designed to work in the ignition system complete with the G-427 generator and the B-300B high-voltage transformer. Allows you to obtain a secondary voltage of up to 18 kV, at a generator rotor speed of 250 to 7500 rpm. The switch is installed in the right toolbox. The base of the commutator is connected to the ground of the motorcycle. If the switch fails, it can be disassembled and repaired
The electronic switch has three output terminals with letter markings on the body<<Г>>, <<К>> and<<Д>>. The ground terminal is the base of the switch.
Caring for the switch during operation comes down mainly to tightening it up threaded connections without allowing the thread to break. It is necessary to protect the switch from moisture getting inside it and onto the terminals from sudden shocks and exposure to high temperatures. You should also systematically check the reliability of the electrical connection between the switch base and<< массой >>, because If this condition is violated, sparking on the spark plug stops.
D1-D226B, D2-D226B, D3-D226B, D4-D817V, D5-D817B, D6-KU201L.
C1 - 1 µF 250 V, C2 - 1 µF 160 V, C3 - 1 µF 160 V.
R1 - 100 ohm, R2 - 1 room.
Point G - 45 volts, Point K - 150 volts, Point D - 0.65 volts.
Installed in the right tool box. From the generator braking signal circuit, through the throttle, which is a device that complements the parametric control of the generator, the circuit of the speedometer, city driving and license plate lighting lamps is powered.
Spark plug Voskhod - spark ignition type A-23
During operation, the spark plug must be periodically cleaned of carbon deposits and the gap between the electrodes must be adjusted, which should be within 0.6-0.7 mm, which is ensured by bending the outer electrode. To seal, a copper-asbestos gasket is placed between the spark plug and the cylinder head. To eliminate radio interference created by the ignition system, a shielded tip of type A-4 is placed on the spark plug.
Headlight Voskhod FG - 133
During operation it does not require special care. Basically, caring for the headlight comes down to removing dust from the internal cavity of the optical element by blowing air.
Ignition switch Voskhod - central switch
Switch 124005490201 is used as a central software switch that provides the necessary switching of lighting equipment on a motorcycle. The switch has three operating positions<<0>>, <<1>>, <<2>>according to the following operating modes:
- pregnant<<0>> - the generator sensor circuit is shorted to ground, which ensures the engine stops.
- pregnant<<1>> (driving during the day) - the ignition circuit is turned on, the direction indicator circuit operates (when the direction indicator switch is on) and the brake signal circuit (when the brake pedal is pressed);
- pregnant<<2>> (driving at night) two circuits turn on:
- a) a circuit of speedometer backlight lamps, license plate lighting and city driving (through the throttle, which serves as a device that complements the parametric control of the generator);
- b) headlight lamp circuit A6-32+32 (via the light switch on the steering wheel).
Caring for the central switch comes down to periodically checking the reliability of the switch in the headlight and cleaning the moving and fixed contacts from dust and dirt by washing them in gasoline.
Switch P-200
Light switch with horn button (located on the left side of the steering wheel). For switching the circuit of the near and high beam A P-200 type switch is used with a built-in push-button horn switch for three operating positions:
neutral - headlight lamp is off;
far right - low beam is on;
far left - high beam is on.
The horn button has a movable contact connected to ground and a fixed contact connected to one of the wires coming from the horn terminal. When you press the button, the contacts close and the signal circuit is completed. Electrical circuit of the Voskhod motorcycle Central switch. 2. speedometer. 3. Speedometer light. 4. Headlight. 5. Headlight lamp. 6. City driving lamp. 7. Sound signal. 8. Direction indicator lamp. 9. Direction indicators. 10. Direction indicator switch. eleven. Electronic switch. (D - sensor terminal, K - ignition coil terminal, G - generator terminal.) 12. Throttle. 13. Relay breaker. 14. Generator. 15. License plate lamp. 16. Brake signal lamp. 17.
Back light
