oldfart
Elite Veteran
Location: Vancouver, Canada
| 4-StrokeI have a four stroke (OS52) in a Schweizer 300 fuselage and it has logged a bit over 130 flights on it now (don't have my log book with me at this time so I can't be exact here) and have no overheating problem. I use 30% CP and an Enya #3 plug.
You will find that you will get the overheating problems etc, if you try to set the throttle curves the same as that of the OS32SX 2-strokes. The OS52-4 power to throttle opening is not very linear. At a half opening setting of the throttle barrel, it will not produce adequate power to hover when the throttle barrel is only opened somewhere in the middle. At half stick, you will find the OS52 will have to be set so the barrel opens about 70 to 75% in order to hover. Also at full open, it does not produce the power of the OS32SX (1.2) but more like the power of the older OS28H (about 0.7). Consequently I would not recommend it for use with any fuselage that makes the heli much heavier then the stock 6lbs or so (The Scale Schweizer only adds a few more ounces as it is basically a pod and boom heli). This is why the 32SX has adequate power when its throttle barrel is opened to 1/2 or less, and the OS52 -4 has to be opened so much more to develop hover power.
Phil |
