Choosing an inflatable vessel to install a 20 horsepower outboard motor is a big step for any hydraulic motor, and it is in this power range that real comfort begins, allowing you to plane with two or three passengers on board without sacrificing maneuverability. PVC boat for an outboard motor 20l s It often becomes a “golden mean” between compact two-seater versions and full-fledged boats.
Modern production technologies allow you to create reliable vessels from reinforced polyvinyl chloride that can withstand severe loads. However, in order to avoid disappointment, you need to clearly understand what parameters are critical for the body-motor bundle. In this article, we will analyze all the nuances, from the length of cylinders to the height of the transom.
Many beginners mistakenly believe that the power of the engine is the main thing, forgetting about the dimensions of the boat itself. In practice, it is the geometry of the bottom and the rigidity of the structure that determine how the boat behaves on the wave. PVC reinforced High density is a material that requires proper tension and assembly to show its best qualities.
Optimal dimensions and length of the body
For effective use of the engine with a capacity of 20 hp, the length of the boat should not be too small. The minimum permissible threshold is considered to be a length of 320 cm, but for comfortable and safe swimming it is better to focus on the range from 340 to 360 cm Shorter models will experience overloads on the transom, and their driving qualities on the excitement will leave much to be desired.
The width of the vessel also plays a huge role in ensuring stability: a narrow boat with a powerful engine can become unstable when turning or landing passengers. The optimal width in external dimensions is considered to be between 145 and 160 cm, which ensures sufficient displacement area.
- 🚣♂️ The length from 340 cm provides a stable output for planing even with full load.
- ⚓ The width of more than 150 cm allows two adult fishermen with equipment to feel confident on the water.
- 🌊 The height of the side is at least 40 cm protects against splashing and increases safety.
It is worth noting that the increase in length has a positive effect on the seaworthinessA long vessel is better at cutting waves, less prone to impacts on water and provides a softer ride. If you plan to go to large bodies of water, such as Ladoga or Onega, it is strongly recommended not to save on length.
On the other hand, models that are too long (over 400 cm) can become clumsy when using a motor of only 20 forces. Here, balance is important: the boat must be long enough for comfort, but not so long that the engine cannot reach its speed potential. The ideal compromise for a 20-horsepower engine is the length of the body 350-360 cm.
Underbody design: NDND or paioles?
The choice of the type of bottom is one of the most controversial among owners of inflatable boats. For a 20 hp engine, both options are valid, but they offer fundamentally different experiences from the control. The payload bottom, assembled from sheets of plywood or aluminum, provides excellent rigidity and flatness.
Hard bottoms allow you to achieve maximum speed and save fuel due to better sliding, but it takes much longer to assemble and disassemble such a boat, and it can be difficult to install heavy floorboards and stretch stringers alone, especially in the field on shore.
Low pressure inflatable floor (NDMAIt's a boat that can be built in minutes, just pumping up the tanks and bottom, and air decks, which are very good at wave shock, and fishing is often the deciding factor, because it's much more enjoyable to stand or sit on a soft bottom.
Technical features of the BNDM
The design of the NDND is a complex system of internal partitions that, when pumped, create a rigid plane. Modern models have a pump pressure of up to 18 psi (about 1.2 atm), making them comparable in stiffness to plywood, but with better absorption of shocks.
It's important to consider that boats with NDND can be sensitive to overheating in the sun when they are parked for a long time. The pressure inside the cylinders increases, and if you don't smear the excess, you can damage the seams. At the same time, solder boats are less demanding to temperature changes, but are susceptible to corrosion of metal elements and rotting of plywood when stored improperly.
- 🛠️ Pied bottom: higher speed, lower price, but more difficult to build and more weight.
- 💨 NDND: quick start, great comfort, best germination on the wave, but higher cost.
- 📏 Transnant rigidity: On boats with NDND, the transnant is often an extension of the bottom, which enhances the design.
When choosing, you should also pay attention to the presence of keel-enhancement On flatbed boats, the keel can often go separately, whereas in inflatable floor models, it is integrated into the design, which affects the stability of the course: a boat with a pronounced keel is better at keeping a straight course when moving against the wave.
Tranch and feed reinforcement
Tran is the most loaded design element when it comes to outboard motors. A 20 hp engine requires a transom that can withstand not only the weight of the motor itself (about 45-50 kg), but also the dynamic loads of shocks to the wave. The standard transom height for such motors is 381 mm (15 inches) or 508 mm (20 inches).
It's critical that the transom is rigidly fixed. High-quality boats use a transmolor plate glued into cylinders and reinforced with a sling or extra linings. Cheap models can have a transmolor that just fits into their pockets -- a 20 hp option that's dangerous, because the vibration of the motor will quickly destroy the fabric.
⚠️ Warning: Never use a 20 hp motor on a boat if the passport says a maximum power of less than 15 hp or if the transom does not have a rigid sticking on the side, this can cause the engine to tear off and the boat to tip over.
The transom material also matters. It's usually a multi-layered plywood coated with water-resistant paint or plastic. When you buy, make sure to check the integrity of the coating. Any scratch to the tree in the contact zone with water is a potential foci of rot. Plywood It must be protected from all sides, including the ends.
For ease of use, many models are equipped with transom wheels. When you install a 20 hp engine, the weight of the entire structure on the transom becomes significant. The presence of wheels allows one person to easily move the boat along the shore without removing the engine. It is not just an accessory, but an important part of ergonomics.
Capacity and passenger capacity
Passport capacity of a boat and actual operating load are often different things. Formally, a boat with a length of 340-360 cm can have a declared carrying capacity of 500-600 kg. However, for a comfortable planing on the engine of 20 hp, this stock must be used wisely.
If you overload the boat, it loses its driving performance: the nose will be delayed, the boat will go into displacement mode or will plane with a large aft trim, which not only increases fuel consumption, but also makes the control dangerous. The optimal load for such models is 2 adults (about 180 kg) plus equipment and motor (about 100 kg).
| Boat length (cm) | Max power (hp) | Whole number of people | Load capacity (kg) |
|---|---|---|---|
| 320 | 9.9 - 15 | 2 | 400 |
| 340 | 15 - 20 | 2-3 | 500 |
| 360 | 20 - 25 | 3 | 600 |
| 380 | 25 - 30 | 3-4 | 700 |
When calculating weight, don't forget the weight of the engine and the full tank. Gasoline is heavy: 25 liters is another 20 kg. Distribution of goods It is also important: heavy things (anchors, batteries) should be placed closer to the center of gravity or on the floor, rather than on the nose, so as not to burrow into the wave.
In some cases, it makes sense to take a boat with a margin of length. For example, a 380 cm model under a 20 hp engine will go very lightly and gently, almost without noticing the waves. This is ideal for those who value comfort above maximum speed. At the same time, "tightening" 20 forces by 320 cm is the engine mode close to the limit for the body.
Materials and tissue density
The basis of the durability of the boat is the quality of PVC fabric. For boats for an outboard motor of 20 hp, it is recommended to use five-layer reinforced material. The density of the fabric should be at least 750 g / sq.m, and for the bottom and the most loaded places - up to 1100 g / sq.m. Thin fabric (600-700 g / sq.m.) will quickly become unusable from shock and friction.
An important parameter is the presence of a protective layer against ultraviolet light and extreme temperatures. reinforced PVC It retains elasticity even in cold weather, and it doesn't become sticky in the sun, and cheap ones can crack on the folds after the active season.
- 🛡️ The five-layer fabric provides protection against puncture and abrasion.
- ☀️ UV stabilizers extend the life of the material in the open air.
- 🌡️ Temperature: quality boats operate from -40 to +60 degrees.
Seams are a weak point in any inflatable design. In premium boats, hot air welding is used to turn the joints of the canvases into monoliths. Adhesives, even high-quality ones, may require revision over time. When inspecting the boat, pay attention to the quality of the gluing of the seams: there should be no bubbles, no adhesives or detachments.
☑️ Checking the quality of the boat before buying
Popular models and manufacturers
The inflatable boat market is saturated with offers, but the leaders remain the time-tested brands. Among Russian manufacturers, companies specializing in boats for harsh conditions. Flagship, Aqua, hunter They have proven themselves to be reliable workhorses.
Foreign brands such as Yamaran or BadgerThey often offer more sophisticated design and ergonomics, but they may be inferior in repairability in remote regions, and when choosing a particular model, you should pay attention to the availability of service centers and the availability of spare parts (valves, remixes) of this particular brand.
⚠️ Warning: When buying a used boat, be sure to check the release date. PVC fabric shelf life is limited, and a boat that has lain in a deflated garage for 5 years can lose its properties faster than an actively operated one.
The 20 hp engine is a great fit for models with an index of 350 or 360 in the title, for example, the boats with a reinforced keel and high-pressure inflatable floor from this line allow speeds of up to 40-45 km / h with two passengers, which is a great indicator for fishing and cruising.
A narrow and long boat will be faster and more economical than a short and wide barge, but if the boat is planned for overnight stays or long stays, width becomes a priority for equipment.
The best choice for a 20 hp engine is a boat 350-360 cm long with an inflatable floor of NDND and a fabric density of at least 750 g / sq.m. This is a balance of speed, comfort and reliability.
FAQ: Frequently asked questions
Can I put the engine 20 hp on a boat designed for 15 hp?
Excessive power leads to the breakdown of the transom, loss of stability and possible rollover, and the engine creates a jet propulsion that can tear off a transom that is not designed for such loads.
What speed will a boat have 350 cm with a 20 hp engine?
With one passenger and a standard propeller, the speed will be about 40-45 km / h With a full load (3 people), the speed will drop to 30-35 km / h, which is enough for safe movement.
Do I need a hydraulic lift (hydro wing) on a 20 hp engine?
For PVC boats up to 360 cm long, the installation of a hydrofoil on a 20 hp engine often gives a positive effect: the boat goes faster to planing, " yaw" decreases and controllability improves at low speeds.
How to keep a boat assembled in winter?
In winter, you can only store an inflated boat in a heated room; in the cold, PVC bluffs and can burst if you move carelessly; in an unheated garage, it is better to store the boat in a deflated, but dry and clean form.