ROTOmotor 125 FS with preinstalled Savex throttle servo


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ROTOmotor 125 FS with carburetor control preinstalled opposed twin cylinder gas engine with electronic ignition.

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The new Roto 125 FS is completely maintenance-free, has high performance and is also suitable for use in aircraft such as the towing machine.

Our developers have managed to tune the engine for the use of propellers with a large pitch to achieve a realistic sound, and therefore we recommend for the Roto 125 FS engine a propeller with a pitch of 14 "Propeller diameters are from 28" to 30 "for two blade propellers.

The maximum engine power is up to 6 kW.

A unique novelty on Roto 125 FS engines is the factory-installed carburetor control. To control the throttle, we chose the Savox SV-1232MG servo, which is verified in practice on our UAV projects.

The reason for this improvement is to make it easier for customers to install the engine on an aircraft, just connect the servo to the receiver and set the servo deflection. The customer does not have to deal with servo levers or drawbars, everything is original from Roto.

ROTOmotor 125 FS is a twin cylinder 4 stroke inline gasoline engine.

The Engine was developed in Europe with the assistance of CAD systems (Solidworks) and optimized for the liquid flow in the Flow software (made by Solidworks).

All ROTO engines and its components are made and programed by utilizing the state of art 5 axis machinery made by American companies HASS and Siemens NX.

Every engine, made by ROTO MOTOR Company is bench tested and adjusted by qualified technician on the Engine Star equipment to ensure its peak performance.

The manufacturing process involves nothing but state of the art equipment including the latest in CNC cutting technology.

  • Technical data

    Engine displacement 125 ccm
    Power 7 HP
    Max static engine thrust 21 kg
    Bore 2x48 mm
    Engine weight 3970 g
    Engine & ignition weight 3140 g
    Arrangement of the engine boxer
    Cooling air-cooled
    Lubrication petrol 92 oct. + 2% oil
    RPM 1100 – 6000

    Fuel system




Recommended props 

Fiala 28/10 to 30/14 2blade

Fiala 26/10 to 28/14 3 blade