Motorized Raft

Motorized raft decision table

The transom decides the motor, not the hull length

Buyers reach for horsepower first and discover the constraint later. On a soft-floor inflatable the limit is the transom: a wooden transom bonded into a 270 cm hull is not the same structure as the one in a 420 cm hull, and the published ratings follow that, not the length alone. The RSD ladder runs 2.5 hp at 210 cm, 6 hp at 245 cm, 10 hp at 270 cm and up to 30 hp at 420 cm — a narrow band, and the top of it is a rating, not a recommendation.

Ask three things before pricing a motor. What is the transom height, in centimetres, so the shaft length can be matched. What material is the transom and how is it bonded. And what is the maximum weight the stern is built to carry, which is a different number from the maximum horsepower — a heavy four-stroke at the rated hp can still be the wrong motor for the boat.

The floor is written into the model code

RSD-AM270, RSD-SL270 and RSD-AL270 are the same 270 cm hull at the same 10 hp and the same 3 persons. The two letters are the floor: AM is an airmat, SL is a slatted floor, AL is aluminium. A listing that says "270 cm inflatable boat with motor mount" has not told you which of the three you are being quoted, and the three do not behave alike once a motor is on the back.

Under power, a slatted floor flexes and the boat stays soft; an aluminium floor holds its shape and lets the hull plane properly, at the cost of weight and pack-down size; an airmat sits between them and is the lightest to carry. If the raft will be run at anything near its rated horsepower, the aluminium floor is usually the honest choice and should be priced as such rather than treated as an upgrade line.

Where a motorised raft stops being the right boat

Above roughly 30 hp the soft-floor programme runs out, and the catalogue steps across to rigid hulls. The aluminium RIB range starts at UL245 with 9.9 hp and 3 persons and reaches 420 cm at 40 hp; the sport hulls begin at SP580 with 150 hp. That is not a gradual scale — it is a different construction, a different price band and a different freight problem.

If the requirement is 40 hp or more, or the boat will be run loaded and at speed regularly, compare against the rigid-hull series rather than pushing a soft floor to the top of its rating. The comparison that matters is not price per metre but what the hull does at the power you actually intend to use.

Quote the hull and the motor as one system

A motorised raft RFQ should compare 2-3 hulls against 1-2 motor options before price enters the conversation. Ask whether the displayed price includes oars, pump, repair kit, seat board, floor and motor-mount hardware, because those six items are where two apparently equal quotes usually diverge.

Separate hull price, motor price, battery or fuel requirement and freight route so that landed cost stays comparable. Petrol outboards and lithium packs each carry their own shipping restrictions, and a quote that bundles them into one figure hides which part of the cost is the boat and which part is the route.

FAQ