Small-sized vessels made of aluminum-magnesium alloy have been occupying leading positions in the Russian market for many years, and the model is a very important one. Bro S 4.20 Classic It combines time-tested design, affordable cost and high maintainability, making it popular with fishermen and hunters alike, and unlike the more simple versions, the Classic has a number of design improvements designed to improve comfort and safety.
When choosing a boat, many users pay attention not only to the price, but also to the real carrying capacity and seaworthiness. Aluminum alloy AMg5MThe silk that is used in production has proven to be very good in harsh climates and aggressive aquatic environments, but in order for a boat to last for decades, you need to understand the nature of its maintenance and select the right attachments.
In this article, we will discuss in detail all the nuances of operation. Bro S 4.20 ClassicFrom specifications to fine tuning moments, you'll learn why this boat is so popular, what its weaknesses are, and how to avoid them, and we'll discuss compatibility with different engines and give you storage recommendations.
Technical specifications and design features
One of the main features of the model is its keel-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bow-bowThe hull is 4.20 meters long, which allows you to comfortably accommodate a crew of 3-4 people. The width of the midsection of 1.60 meters provides good stability, allowing you to feel confident even when moving inside the cockpit.
The design is widely used flat-bottomedThe bottom and sides are usually very thin, but for this model, the standard is to use sheets 2 mm thick, which is the optimal balance between strength and weight. The transom and cheekbones angles are reinforced, which prevents deformation when you install powerful motors.
- 🛶 Length overall: 4200 mm
- 📏 Overall width: 1600 mm
- ⚖️ Weight of the body: about 75-80 kg (depending on the configuration)
- 👥 Passenger capacity: up to 4 people
- ⚓ Height of board: 0.55 m
It is important to note that cross-board In this model, reinforced and designed to install outboard motors up to 30 hp (although data-sheet figures may indicate lower values, the safety margin allows short-term use of more powerful units).
⚠️ Note: Do not exceed the maximum recommended engine power specified in the boat's passport, which can lead to instability and sinking of the boat, especially in windy weather.
The design provides for the existence of timber The riffled floor surface (if fitted with the Classic) is not only pleasant to the touch, but also prevents slipping, which greatly improves safety when fishing.
Materials and build quality
The main material for production Bro S 4.20 Classic is aluminium-magnesium alloy AMG5MThis material is not corrosive in salt water, does not rust and has a high ductility, and when it is impacted, the sheet does not burst like steel or duraal, but only deforms, making it easy to reshape the body.
The quality of welds is a critical parameter for any aluminum boat. In the factory, welding is done by argon-arc, which ensures tightness and strength of joints. The seams are smooth, without burns and sinks. However, before the first descent, it is recommended to carefully inspect all joints.
Painting and protection uses powder coatings that are applied to the prepared surface, which are resistant to mechanical damage and ultraviolet light, but over time chips can appear on the bottom, which require timely repair to prevent oxidation.
Inside the body are often installed floating-block They do not absorb water and retain their properties throughout the life of the vessel, and the presence of such blocks allows the boat to stay afloat even if it is completely filled with water.
Comfort and Ergonomics: What's Inside?
The water is made up of a lot of little things, and the Classic has tried to take into account the basic needs of the fishermen. banco They're very comfortable, they're made of the same material as the body, and they often have a corrugated surface.
There are easy areas for the installation of navigation devices and sonars, and many owners immediately mount them. windshield It's an optional fence, or a separate one, and it's a great way to get out in cool and windy weather.
The system deserves special attention. drainageThere are holes in the bow and cockpit to quickly remove off-shore water, especially when caught in a wave or when rainfall hits.
☑️ Verification of ergonomics before purchase
The interior space allows you to install battery-box And a fuel tank of sufficient volume, and the rational use of the cockpit space allows you to place gear and equipment without cluttering the passageway.
Operation and selection of motor
Selection of engine Bro S 4.20 Classic It's a balance between speed and efficiency, and it's a great plane boat with engines ranging from 9.9 hp to 15 hp, and it's a middle ground, and it can go up to 30-35 km/h with a full load.
When installing the motor, it is important to choose the right one. lower unitThis model is optimal for the length of the "S" (short leg), although many use standard legs to adjust the position of the motor on the transom, it is important that the anti-cavitation plate is at the same level with the plane of the bottom.
The table below shows approximate speed indicators depending on the engine power and load:
| Engine power (hp) | Loading (kg) | Speed (km/h) | Mode of traffic |
|---|---|---|---|
| 9.9 | 150 | 28-30 | planing |
| 15.0 | 200 | 32-35 | planing |
| 18.0 | 250 | 35-38 | planing |
| 5.0 | 100 | 12-14 | Displacement |
When operating in shallow water, it is recommended to use hydrofoil It's not only improving the efficiency of the propeller, it's also protecting the lower unit from impacts to the bottom by taking some of the load on itself, and it's also improving the hydraulic wing's planing output.
⚠️ Warning: Avoid sharp steering when driving at high speeds, which can cause the boat to roll and tip over, especially when it is heavily loaded.
And trolling is a great way to do this, with electric motors mounted on the nose or transom, which are silent and don't scare the fish, and they let them go at slow speeds for hours.
Tuning and improvement DIY
Owners often rework Bro S 4.20 Classic One of the most popular improvements is the installation. pulp It's a long handle, or a remote control, which makes it more comfortable to drive the boat, especially when paired with a cable-controlled gas.
To protect the bottom from stones and sand, many install lease Or extra polyethylene pads, which extend the life of the hull when you're on frequent beach, and keel protection is also popular.
The secret to quiet work
Many owners paste the inner sides and bottom with vibration insulation material (noise insulation for cars), which reduces the hum from waves and shocks, making staying in the boat much more comfortable, especially when talking.
Installation anchor-box The bow is another useful upgrade, which allows you to store the anchor and the phala in one place, preventing them from getting tangled, and it also serves as an additional buoyancy and weighting of the nose.
For night fishing or parking is indispensable tent-coverIt protects against dew, rain and insects, and the tent frame is usually made from dural tubes, and the tent itself is sewn from dense, impregnated fabric.
When installing additional boxes or knobs inside the boat, be sure to lock them firmly or use storm mounts. Shifting cargo on the move can be dangerous.
Care, storage and transportation
An aluminum boat requires no maintenance, but minimal rules must be followed, and after every trip, especially on salt water, the hull should be rinsed with fresh water, which will wash away salt and dirt, preventing oxides from appearing.
When transporting on a trailer, it is important to properly lay the boat on the road. laying-pieceThey must repeat the contours of the hull to avoid point loads, and the speed of the boat on the trailer must not exceed 80-90 km/h.
For winter storage, it is better to turn the boat upside down or install it on special goats, which will provide ventilation and eliminate the accumulation of moisture and snow inside, and the engine must also be preserved according to the manufacturer's instructions.
⚠️ Warning: Do not keep the boat assembled with the motor mounted on the transom for a long time without support. this can lead to a deflection of the transmolatory board.
Check your condition regularly fixation The tins, the switches and the attachments, the vibrations on the move can weaken the bolt joints, the timely lifting of nuts will relieve problems on the water.
Frequently Asked Questions (FAQ)
What is the real load capacity of the Bro S 4.20?
rated carrying capacity is usually about 400 kg. However, in practice, the boat can withstand heavy loads, but it reduces the buoyancy and increases draught. For safe plane with full load, a motor of at least 15 hp is recommended.
Do I need to paint the boat inside?
The factory paint is quite protective, but if you're planning to operate actively, you can put an extra layer of epoxy paint or rubber mastic on it, and it also reduces noise.
Can I put the engine 20 hp?
Technically, the transom will withstand such a motor, and the boat will go faster, but it is worth considering that this increases the risk of loss of control on corners and increases fuel consumption.
How do you fix a hole in aluminum?
Argon welding is best used to repair holes, and in the field, you can use aluminum crumb epoxy compounds or special repair tapes, but this is a temporary measure until a full repair is completed.
The Bro S 4.20 is a workhorse for fishing and hunting, which, if properly maintained, will last a very long time, and its simplicity of design makes it easy to repair any damage.