Driving pinions and more!

The contents of the bag has been enriched with four plastic gears engines, although helpful to replace the original brass gears that come to wear while eating dirt or hard debris atterrrissage.
Will avoid the replacement of engines for this reason alone, and destroy repeated the brand new gear that you install.
Do not hesitate to replace one axis légèremnt very distorted, it generates vibration and a reduction in yield that reduces the independence and accuracy of the flights.