Moped "Alpha" (72 cubic meters): specifications

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Moped "Alfa" (72 cubic meters) is the most common means of transportation among lovers of light motorcycles. This is due to the price of this equipment, its functionality and maintainability. Cross-country ability, speed and a small amount of fuel that is necessary to ride this vehicle put the Alpha moped (72 cubic meters) in popularity on a par with the most famous Japanese brands. This is no coincidence, because the engine that is on these light motorcycles is an exact copy of the Japanese "Cube" from the company "Honda", which is comparable in reliability to the AK-47. Single-cylinder engine 139 FMB with a volume of 72 cc. cm works in all weather conditions and does not need frequent repairs and replacement of spare parts. Technical data allows you to use this vehicle in the most extreme conditions, including driving in the cold, on sand and on any off-road. This is the best light motorcycle for Russia. In rural areas, you can most often find the Alfa moped 72 cubic meters. The photo of this model is easily recognizable. Simple and concise design, low price,good speed, cross-country ability, maintainability, efficiency and a number of other advantages - this is what underlies the reputation of this mode of transport.

Unique cross-country ability

The record holder for cross-country ability among light motorcycles is the Alfa moped (72 cubic meters). The characteristics of its engine, dimensions and weight are very significant advantages. The ability to overcome any off-road at the Alpha is due to its light weight - 81 kg. To ensure confident movement on sand and mud, such light equipment does not need a powerful and heavy motor. If there is a need to overcome a patch of deep and viscous mud, a steep climb on the sand, or to ford a shallow stream or river, you can always get off the moped and help it cope with a difficult section of the road, pushing it forward like a bicycle.

Due to the fact that the wheels of the "Alpha" are thin, they can get bogged down in the wet sand under the weight of the rider. But without the latter, this moped can be dragged along any off-road, helping it with the engine in first gear at low revs. In urban conditions, if necessary, to cross steps or high curbs, the Alpha can be raised in the same way as a conventional bicycle. That's why the most remote corners in the forest, on the banks of the river, which can only be reached by bicycle, are accessible to this light motorcycle. Many lovers of hunting, fishing and mushroom picking prefer this particular moped because of its light weight. For heavier and more powerful vehicles, drive along the path blocked by a fallen treein the woods would be an impossible task, but for Alpha no problem.

Good speed

The speed ceiling for this moped is 70 km/h, which is quite enough for driving on the highway. The mass of the "Alpha" is small, and controllability at higher speeds is noticeably lost. Some fans of this technique are trying to modify the Alpha moped (72 cubic meters), put a more powerful piston, zero resistance filter, stars with an increased gear ratio, modify the ignition system, putting it ahead of the curve, and achieve an increase in speed up to 90 km / h. But for driving around the city in traffic jams, on country roads, on dirt and gravel, the speed capabilities of Alfa are quite enough without all these modifications, moreover, with an increase in power and speed capabilities, many important components and assemblies of the moped begin to wear out faster.

Alpha's design allows you to install more "solid" engine options on it, bringing its power up to 8 liters. With. But Alfas with such engines often require repairs, the service life of the most important elements of the undercarriage is noticeably shorter, and they also begin dangerous vibration damage. A more powerful motor would require an increase in the mass of other structural elements. This would be a loss of many advantages, especially in cross-country ability and efficiency, which the Alpha moped (72 cubic meters) has. The speed characteristics of these mopeds are perfectly balanced with the lightness and strength of their construction and chassis.

Engine

The reliability and unpretentiousness of the 72-cc four-stroke engine "Alpha" due to its perfect design, developed by Japanese experts. Even in a somewhat simplified version, with the use of cheaper materials and lower quality requirements for components, the 139 FMB engine works surprisingly reliably, which indicates the balance of all its structural elements. The power of this motor is only 5 liters. with., and the maximum number of revolutions per minute is 7500. However, thanks to a well-thought-out transmission with four gears, the Alpha engine copes well with standard loads in all ranges of its gearbox capabilities.

Engine design

The design of the motor is very simple. There are two valves in the cylinder head - intake and exhaust. Their work is provided by a timing star located in the same place, the rotation of which occurs synchronously with the magneto through a chain drive. On the left side of the engine is a foot shift lever that controls a very simple system of gears mounted on two parallel shafts in the crankcase. The oil pump is driven by the timing chain and is located under the crankshaft. On the right side of the engine, inside the crankcase, there is a clutch block, which is controlled by a lever using a clutch cable coming from the left handlebar.

Prevention and repair of the Alpha engine at home

The engine of the "Alfa" moped (72 cubic meters), like any other vehicle, requires regular maintenance and repair. Regular oil changes are an important condition for extending its life. The oil change process is very simple. The engine warms up, then turns off, and with the help of a drain hole located under the crankcase, the used hot oil is easily removed from the crankcase into a specially prepared container. Then new oil is poured. Setting up the correct operation of the engine begins with adjusting the carburetor, with which you can enrich or lean the mixture. It is also necessary to regularly check the operation of the valves, setting the necessary clearances using a special probe of 0.5 mm. Two or three times per season, it is necessary to check the timing chain tension, as well as the condition of its tension mechanism, rubber rollers and dampers. Any breakdown of the Alpha engine is easily repaired. In case of loss of thrust, it is necessary to remove the cylinder head and check the integrity of the valves. Valve burnout is one of the possible breakdowns of this motor. To restore their performance, you need to clean them and re-grind with paste. This procedure is familiar to many owners of old Zhiguli models. If the timing chain breaks, it is necessary to remove the generator rotor and replace all elements of the gas distribution mechanism, and when assembling the engine, you need to make sure by marks that the generator rotor and timing star are synchronized with the correct cylinder stroke.

The clutch must be disassembled and washed in gasoline once a season, as a viscous mixture of oil and metal powder accumulates inside it. With regular inspection of the engine, correct tuningand replacement of parts showing signs of wear 139 FMB will work flawlessly. Repair of the Alpha moped (72 cubic meters) does not require serious capital investments and can be successfully carried out with minimal skills and abilities at home.

Recipes for increasing power 139 FMB at home

The most common way to increase the engine power of the Alpha moped is to replace the piston group with a version with a large cylinder volume. As a rule, such a replacement adds power to the motor, but does not greatly affect the increase in the speed of the moped. There are other ways. The simplest is double ignition. You can make a step on the protrusion located on the generator rotor housing by sawing off a 0.5 mm layer from half of its metal surface, from the edge that first touches the sensor during the working stroke of the rotor. This will give an increase in power by 5-10%. You can increase the diameter of the intake and exhaust valves. To do this, bore holes in the cylinder head for wider valves taken from the 139 FMB piston group with a larger cubic capacity. This operation gives an increase in power by 15-20%.

Maintenance and repair of the running gear of a moped

Repair of the "Alfa" moped (72 cubic meters), caused by major breakdowns, can be completely eliminated by regular preventive replacement of those parts that have obvious signs of wear. The chain on a moped should be replaced after every season or after 2000 km. The chain is stretched very significantly, whichincreases the wear of both stars. A chain break at high speed can cause the rear wheel to suddenly lock up, which can lead to a dangerous fall, injury and even more damage to the motorcycle. On the road, this situation can cause the destruction of the rear wheel tension elements, severe deformation or complete destruction of the tension mounting sockets. Artificial shortening of the chain contributes to the rapid wear of both stars. Tires after 7,000 km of run completely lose their tread relief and traction. They need to be changed after 2-3 seasons of operation. Clutch, fuel and front wheel brake control cables should be shortened after each season due to stretching. The rubber bands in the brake drums are gradually deformed, which increases the play of the wheels. It is also best to change them after each season of operation.

Vibration destruction

Some breakdowns of a moped may be associated with the destruction of its load-bearing elements. The plastic front fender on the Alpha lasts longer than the metal one, as it is less susceptible to the negative effects of vibration. The engine mounts on the frame can also collapse due to vibration. To avoid this, it is necessary to weld wide washers on them. The battery after 2-3 seasons loses up to 50% of its capacity, therefore its regular replacement is also desirable. Electrical clutch and turn signal control sensors should work normally. Both safety during movement and correct control of gear shifting depend on them. Established rearthe shock absorbers on the Alpha wear out, which can lead to unwanted friction between the rear wheel and the inner surface of the rear fender. There are deluxe versions of the rear shocks for the Alpha, which allow you to put thick tires on the rear wheels, as they can be used to slightly raise the rear of the motorcycle. Serious problems with the repair of this moped are unlikely if you handle the fasteners with care.

Running

The running-in of the "Alpha" moped (72 cubic meters) does not take much time and has several main conditions for obtaining the correct result. It is necessary to strictly observe the speed limit up to the first thousand kilometers, do not overheat the engine, forcing it to run at maximum speed for more than 20 minutes, and also change the oil after 500, 1000, 2000 and 5000 km of run.

Modifications

Overview of the Alfa moped 72 cu. will not be complete without listing its major modifications. There are two frame options for this moped. This is high, with a place for a large gas tank, and low, where the gas tank is small, and above it is the trunk. According to their characteristics, both versions of the moped will be almost the same, with the exception of the difference in the volume of gas tanks and a slight difference in landing height. Alfa is made by a number of Chinese manufacturers, so there are many parallel names for the same model. For example, the Omax Alpha moped is 72 cu. is a purely Chinese version, and the Orion moped is 72 cc. - Russian assemblythe same model from Chinese spare parts, carried out at Velomotors enterprises.

Options

Existing modifications of Alpha (72 cubic meters) may differ in some design elements. There are also luxury versions of this moped. For example, the Alfa Racer moped 72 cc. has a more spectacular and dynamic shape of the seat and stands out from the background of the rest of the "Alpha" spectacular sports contours of the gas tank. In fact, this is the same model of a moped. In luxury versions, hydraulic rear shock absorbers, alarms, plastic fenders, more attractive decor elements, slightly more expensive turn signals and headlights, an expensive wardrobe trunk and even leatherette flip-up bags can be installed. But it will still be the same 72cc Alfa moped, with the same specifications but 30% more expensive.