General selection criteria to find the correct TORCMAN

Presently engines with four different diameters (stator diameters 28, 35, 43 and 68.5mm) are available with up to four different stator lengths (from 5 to 40mm) - in total 12 different sizes. They cover the power range of approximately 50 - 4000W and allow to find a suitable motor for almost any application of electrical models from the Slowflyer to the large Scale Model, from the Mini-Heli to High-Performance Helicopter. The rotation speed of each type of engine can be adapted within a wide range (4000 - 16000 U/min) by variation of the number of winding turns. Particularly for the electrical flight the tuning of propeller, battery and engine plays an extremely important role, so this flexibility is a big advantage of the used engine principle.

For applications which require higher revs (10000 - 16000 U/min), in particular for helicopter drives, the 10-pole engines have proven to be the better choice, since they turn about 30% faster than the 14-Pole versions. Therefore, all engine sizes are available as both 10- and 14 pole versions, except the Monster (TM685) .

New in TORCMAN's product portfolio are outrunner motors with planet gears. They allow a by factor 2 to 3  increased power throughput with the same motor size and bigger prop sizes, while weight and size remains reatively small. Of course the use of high precision  and high efficient planet gears from Reisenauer drives up the price, and therefore these drive sets should only be used where directly driven outrunners cannot compete.

You can find an overwiew of the available standard motors by clicking this link

The following table shows, that the motor windings have extremely low impedance, since about 25% of the engine weight are allotted to copper in the coil.


Length w/o

Outer Diameter

Power Range


TM280-05 26.0 34.4 40 - 100 55g
TM280-10 31.0 34.4 75 - 150 80g
TM280-15 36.0 34.4 100 - 250 106g
TM280-20 41.0 34.4 200 - 350 132g
TM280-30 Triton 60.0 34.4 350 - 600 200g
TM350-12 40.0 42.0 120 - 350 160g
TM350-20 48.0 42.0 250 - 600 220g
TM350-28 Triton 67.0 42.0 500 - 900 310g
TM350-12 Super-Man 69.0 42.0 800 - 1200 250g
TM350-20 Super-Man 77.0 42.0 1000 - 1800 305g
TM430-20 53.5 52.0 500 - 1000 370g
TM430-30 63.5 52.0 800 - 1500 500g
TM430-40 Triton 89.0 52.4 1200 - 2000 650g
TM685-20 79.0 82.0 bis 1500 1000g
TM685-30 89.0 82.0 bis 3000 1250g
TM685-40 99.0 82.0 bis 4000 1500g

The exact outside dimensions can be found under the column Motors of the respective types.

Dependent on the model weight and desired motorizing, a rough selection of the engine size (type) is the first step. Also the type, size and number of battery cells mostly accompany with the size of the model. Under the column Configuration - Wing Models or Helicopters you find an overview of the most usual model types and the suitable engine sizes. Our practical samples on the website show a lot of successful application examples from our customers and may help you selecting the correct drive set for your model.

The diameter of the TM280 series is about 35mm, and so it fits well into slim fuselages of small models. Depending on the length of the stator (5, 10, 15 and 20mm) the power ranges from 50 to 350 Watts. With sufficient cooling also far higher power is possible for short time.

The diameter of the TM350 series is 42mm and fits thus well into most fuselages with 42 to 44mm front frame. Three lengths are available for selection with a power range from 250 to 900 Watts.
With the geared version, the mounting rib and spinner can be reduces down to 38mm.

If power above 800Watt is required, the TM430-20 or TM430-30 should be selected. It covers the range upto 1800Watts and has an outer diameter of 52m. Of course one can, if available, select the next longer version to have sufficient reserves for future models.

If this still isn't sufficient, it's time for the Monster (TM685). This huge motor is available in 3 lengths and allows to drive with upto 4000Watts really big props upto 28"diameter. appropriate controllers are the Jeti Spin99 (685-20) and the Spin200 or Kontronik Power Jazz for the TM685-30 and -40.

As rule of thumb is considered

  • for electric glider models and slow Scale models approx. 100 to 150 Watts of input wattage per kg model weight  is recommenden, for big scale gliders with SLS-System 80 - 1000Watt is sufficient.

  • for sportive gliders 150 -250Watt/Kg allow easy take off by hand and fast climbing

  • for Hotliners and motor models approx.. 200 - 400 Watts per kg, depending on expected flight performance and engine running time, for dynamic acro flight, 200 - 250Watts are fine.

 All information without engagement - technical data are subject to modifications