What an adventure!! I did not realize that he planned that long trip. I thought it was locally around Africa which must be an adventure enough.
The CB750 will work fine. Stock compression can handle low octane fuel. If pinging, turn the point plate a little clockwise. If grooves are not long enough open the point gaps a little. Points can be repaired too if broken.
I got one broken in France once, a shop used another point part and put it together. It was the moving part with bakelite shoe against cam.
Oil, fuel and let it run min 5000 rpm to ensure charging.
I guess wild animals and uncivilized persons are to watch out for