Unlike cars or plastic boats, made by stamping method and that's why so similar in motion with a motor and under oars, outboard motors are assembled manually, as well as inflatable boats. Therefore inflatable boats also behave different on the water. One of reasons is different configurations of the hull bottomm, which possesses the special hydrodynamic specifications. It's necessary to choose the best place each time when installing a motor on the boat, what generally is a long procedure. Most manufacturers of inflatable boats and especially RIB's make measurings  beforehand and mark outlines of the motor fastening on the boat transom. Thus they specify to a user, that this is the best place of motor fastening. However, acknowledging ability of the workman to create a good, beautiful and reliable inflatable boat, we can not be sure that  manufacturer of the boat simultaneously is an expert of motors, especially for such difficult product, as Rigid Inflatable Boat. There are specialists, armed with the best tools and scientific knowledges of hydro- and aerodynamics, who can tune a ship in ideal way for races on record speeds. Taking the most powerful engine, such specialist will always hang it on higher on the transom, will displace it closer to the starboard, what provides better speed indexes and manoeuvrability of the ship during races, but such motor hanging  is not always the best.

Shape of the bottom, distribution of the load, engine sizes and its weight with respect to boat mass and, foremost, type of the propeller - all these influences the choice engine installation place. We will consider for example a 5.5-meter inflatable boat with a smooth plastic bottom of "deep V" type with the management control, four seats, fuel tank, top as the A-shape frame, remote control and outboard motor of the medium size of 50-115 HP.

By theory, a motor should be displaced to the starboard on 5cm for compensation of revolving moment, which is created by propeller rotation. Such small displacement can be enough for compensation of boat "withdrawal" because of propeller revolving moment, although such recommendations do not work with some bottoms. The more shallow is the "deep V" type, the less displacement to the starboard is required. More deep bottom at the same time will require greater motor displacement on the transom. Some bottoms have special profiles, which compensate this force. This boats might not require displacement of the motor from the central section.

When you define desired motor relocation on the transom, its necessary to choose right height of motor installation. It will appear thus, that major, if not the main, is distance from the bottom edge to the anticavitation plate on the motor dead-wood. Anticavitation plate should be located 2cm higher than bottom edge of the boat. Such installation provides the best conditions for outboard motor exploitation. Motor always can be lifted from this position up by traditional lifting facilities, step by step, to choose suitable height of hanging on the different rates of movement. In general, the higher motor is hung, the better it works, certainly, if not take into account damage of cavitaion to the propeller and motor.

A standard 5,5-meter RIB should allow to displace a motor on one motor fastening ear without necessity of changing the propeller. Anticavitation plate can be placed for this purpose approximately 4cm higher than bottom edge line: this will simplify regulation of motor height position and at the same time will improve speed specifications of the boat. Moving anticavitation plate away from the bottom edge should be accompanied by displacement of motor on transom relatively to the central section of the boat hull.