No matter with RTF-Helis. (ready to fly), but even with some bigger helis and latest with the redesign, one comes to the question of the right drive.

The experience showed, that a 8-cells-battery, eg. by ECO7, 8 and Royal is not use for flying. The engine speed of the rotor is small and makes the heli very slowacting. Only with 10 cells a tidy fly is ensured.

Brushtype engine
"A good and very durable driving motor is the 'BB650 Race' in connection with 10 cells and 12 pinion. With this combination, I have approx. 200 battery charges to fly them before coals and magnets were finished.  The engine is not repairable and costs about € 45, and has a built-in cooling fan "

Brushless engine
Meanwhile, the prices for the Brush Less  motors and regulators dropped. The brand manufacturers from China have incredibly low prices for some Best quality. Also, the use of LiPo-Accus reduces the ballast and almost doubled the flight times.

This new technology requires increased attention to the maintenance of motor and battery. For LiPos used an intended charger, otherwise there is danger of explosion! The engines are strongly rim hole and almost wearless. Often, the fixing and the pinion have to changed against a conventional engine.

Freewheel
Often, the only optionial available free run of the main shaft is a must-have. Without this free run the big gear damaged already by first block of the rotor blade. Besides of failure of the drive the helicopter crashes suddenly!

The Radio Controller
The pinnacle of the sport model has the name not only because of the complex technology of Helicopters, no also the control of the aircraft unit is a class of its own. The control movements have times sensitive, times energetic. We are no more succeded with the hand-held R/C. In oder to make it short, it is  better, to insert the transmitter is a desk.

The Training Rack
It may be tinkered from carbon fiber tube 6mm and at the ends, with hot glue fastened styrofoam balls of about 5cm (2") in diameter. Small Helis get by 3mm carbon fiber rods, and fastened ping pong balls at the end.
However, these racks serve only the calming of the pilots. The heli never mind. He stands with and without safe during takeoff and landing!. A heli not toppled down easy. But these racks encumbered him at the right flies. Later you will noted it by the detach.