ORIGINAL: Jezmo
I just finished my GP Big Stick 60 and put a Saito 91 on it that has been converted to run on gasoline/oil mix. I flew it for the first time this weekend and I was impressed with how strong the engine is on gas. I kinda expected to lose a little more power than it did but who's complaining. It went down from 9800 running on 15% glow fuel to 9400 on 16:1 mix gas/oil. The engine has about 10 hrs. on it as a glow from it's previous life and now has about an hour and a half as a gasser. About an hour of that is on the test bench figuring out what it likes for timing and such. I did not use a pumper type carb instead using the stock glow carb. It runs surprisingly well and the needle is less sensitive than my SuperTigre 51 on gas. It's still a little sensitive just not as much so as the ST. I intend to start cutting back on the oil to numbers more inline with what Saito is recommending for the G36. The 16:1 brew was already available from my SuperTigre 51 project so I have been using it. It starts super easy and idles reliably down to 1400 with the 14X6 prop I have on it.
Here are a couple of pics of it. [8D]

[8D]
Edited to add: The ignition is CH and is one of his top of the line with synchro spark.
Hello jezmo
I also converted my 90 st, but I used a carburetor walbro, because with his original was unusable for intermediate regimes.
In your 51 st carburettor which uses?