What Size for Inflatable Boats

What Size for Inflatable Boats

Most of us wanted to have a portable and convenient boat that we can bring every time we go fishing in many places we want. However, we don’t know where to get that amazing stuff. Now, I’ll tell you everything about it. Generally, inflatable boats are a lightweight boat that was constructed with its sides and bow that is made of flexible tubes containing pressurized gas.

The hull and floor are commonly flexible for smaller boats longer than 3 meters which are 9.8 feet. The floor consists of three to five rigid plywood and aluminum sheets that are fixed between the tubes but are not connected rigidly together. The transom is rigid which provides location and structure for mounting an outboard motor.[read more]

However, some inflatable boats can be disassembled and packed in a small volume to be easily stored and transported. When inflated, the boat is kept rigid cross-ways through a foldable removable thwart. This amazing feature makes these boats the best for life rafts for bigger boats or aircraft and for recreational and travel purposes.

The Two Types of Inflatable Boats

There are two types of inflatable boats that have a different purpose, uses, and structures. Let’s now dig into it!

Rigid Inflatable Boats

inflatable boats

This rigid inflatable boat or RIB is a development of this inflatable boat. It has a rigid floor and a solid hull. The hull’s external shape helps the boat cut through waves and gives a more comfortable ride when traveling fast even in rough conditions. The design and structure of the hull can support a more powerful and amazing transom mounted outboard engine or even an inboard engine. This rigid inflatable boat is commonly used for short scuba diving excursions.

Soft Inflatable Boat

inflatable boats

This soft inflatable boat (SIB) lacks a solid hull, unlike the RIB. It commonly has a removable slatted floor that allows the boat to be deflated and can be easily transported in a car or any vehicle. This boat has a low draft and is useful for traveling across the shallow water like beaching in places without landing facilities.

Some soft inflatable boats have a rigid transom which means, they can support an outboard engine. Inflatable boats that have transoms also have an inflatable keel that creates a slight V-bottom along the line of the hull. It improves the seakeeping of a hull and directional stability.

The vessels of SIB are lightweight. It is best to put weight in the bow area if powered with an engine, to keep its bow from rising while the boat is going up on a plane.

There are several floor choices available for soft inflatable boats. These are the roll-up slat floor, the hard floor which is made of aluminum, fiberglass or wood panels. There is also ribbed air floor exclusively on inflatable rafts and high-pressure air floor.

What Size Motors for Inflatable Boats?

Here’s the guide on how to decide what size of inflatable boat you want to choose. The size of your inflatable boat depends on the capacity or horsepower (hp) of your boat’s motor.

2hp-4hp Outboard Motors

inflatable boats

These outboard motors usually weigh less than 19 kilograms. Small outboards are common for portable boats like folding boats, canoes, dinghy’s, small sailboats, small pontoon boats, and inflatable boats and other lightweight boats. These kinds of outboards have two strokes but four-stroke engines start from 1.5 and up. They do not have gears even some might have Drive and Neutral. The whole outboard commonly rotates 360˚ which is good for short maneuvers in reverse. The small outboards are relatively lightweight and have a carrying handle. While a little heavier for those who have four-stroke engines.


These small outboards can push small boats up to 8 to 15 kilometer per hour depending on power, boat design, weight, and current.

5hp-6hp Outboard Motors

inflatable boats

This hp range of outboard motors is great and ideal for different applications like inflatable boats up to 3.5 meters in length, larger canoes, portable folding boats and 2.5-3.5 meters dinghies and inflatables. Hulls weigh up to 115 kilograms and require a short shaft which is 15 shaft length outboard motor. This hp range is also available in 20’’ long shaft configuration, ideal for trailer yachts and trolling motors for hulls less than 6 meters length. The engines in this hp range have 1 cylinder even 2 cylinders do exist. With these small motors, heavy laden boats will not perform well.


In this range, the engines will propel most hulls at approximately 16-28 kilometers per hour one person and even in light load. Engines are lightweight, easily transported, compact and have many forward-neutral-reverse gears.

8hp-9.8hp Outboard Motors

inflatable boats

This hp is small yet powerful and is popular with inflatable boats of 3-4.5 meters, larger portable folding boats, aluminum boats that have 3-4.5 meters in length and lighter fiberglass boats up to 4.5 meters. These hulls weigh to 136 kilograms and really require a 15’’ short shaft length outboard. In this hp range, engines are also available in 20’’ long shaft and 25’’ extra-long shaft length which make it the best choice for trailer yachts to 7 or 8 meters.

Most engines in this range run smoothly in 2 cylinder outboards. The outboards come with a 24L separate fuel tanks while for strokes may have an 11-liter tank.


Engines in this range will drive most hulls at 15-28kmh with 1 to 2 persons or light to moderate load. They are a great choice for trolling motors, auxiliary outboards, and yacht motors.

15hp-25hp Outboard Motors

inflatable boats

These motors are quite heavy to handle yet they are considered to be as a small outboard motor. This hp range is popular for use with inflatable boats which are 10-14 feet, flat bottom boats 12-16 feet in length, aluminum fishing boats 12-16 and fiberglass boats which are 12-16 feet in length. These kinds of hulls also require a 15’’ short shaft length – 20’’ shaft length.

Engines in this hp range are also available in 15’’ short shaft and 20’’long shaft which is ideal for river trolling like auxiliary motors and heavier trailer yachts.

Advanced features are present in newer four-stroke outboards in this range. It has audible and visual warning indicators for overheating and low oil pressure. They are commonly smooth running and come with auxiliary fuel tanks.


In this range, engines will propel hulls around 40kph with moderate to heavy load.


Motors are very important when fishing or doing some outdoor activities like fishing. I hope that this article will help you find the best motor size for your inflatable boat.

2 thoughts on “What Size for Inflatable Boats

  1. boat Engine Cover says:

    Here will be the main varieties of motors readily available for your watercraft:Outboards:One of the most
    popular boating motors, outboards are ideal for smaller boats.
    If the brakes feel a little soft, or are making a noise,
    then [replacing the brake pads could fix the problem. The ports include the way of gas entry and exit in the combustion chamber.

  2. Anonymous says:


Comments are closed.

Recent Posts