People may think that more pitch will load the engine more and in the heat you want to go the other way around, well that would be true if the air density was kept the same. But in hot days air is less dense and it requires more pitch to load the engine the same way.
One feature I love about this engine is that it does not change much with climate and if I use the same prop it will work well. As matter of fact I did that for one whole season. But then I noticed that using more pitch I would get better line tension in those hot days and no wind, and it would wind up less in cold and windy days with less pitch.
The nice thing about wood prop is that in a bag of props we get all sorts of pitch. I have a set of TopFlite 14x6 from 5" to 8" in real pitch.
The JXF vary less in pitch and I have been buying 14x6 and 14x7 and I have a set of props with pitch from 5.4 to 7.6. The hard thing is to find two props with the same pitch. They also vary pitch from one blade to another . I guess this is old news, but I thought I would mention it again in case some one does not know how wood props really are.
So if you use a wood prop and it dos not work well, dont give it up so fast, try another one and check the real pitch.
Martin