Kjetil
Senior Heliman
Location: Oslo, Norway
| Dusty,
The manual says that there are different gear ratios available. There are 14, 15 and 16 tooth pinions and 124, 126 and 130 tooth main gears. The stock is 15T pinion and 124T main gear which gives a gear ratio of about 8.27 (124/15). In my opinion, one of the pros with the N9 is that the power train runs very smooth and free, and the power from the engine is transferred to the blades with very little loss of power. In other words, my engine runs better and with less load through the same maneuvers comparing it with other helis I've had. So the YS91 should be happy with 8.27. Nigel Brown uses an YS91 with the stock 8.27 gear ratio as far as far as I know, and his engine sounds happy.
Hope this helps
Kjetil |
