I know it's already been mentioned above but gasoline has more lubricity than methanol hence the need for less oil. I ruined two rods on my ST51 trying to run the ratio in the 25:1 range. It now has over 75 hrs at 16:1 so that is what I have adopted as my standard. My G90 that is still running the bushing rod might get away with the 25:1 ratio but I haven't been willing to push my luck. The one with the needle bearing rod (like Ken Lambert's and the BME) works just fine at 40:1 and Ken says his is OK at 50:1. I am running my Saito 91 converted to gas at 22:1 and have had zero problems with it. When I remove the back cover to check the condition there is plenty of oil inside.

I'm with the others that anything smaller than a 50 size might be adding too much weight. Some of the weight is offset by the need for less fuel to get the same flight time though. About half the fuel for the same run time on all my gasser conversions is normal and the Saito might be just a bit better. More like 2.5 times.

The ST51 is running on race gas with a much increased compression ratio (no head shim and a GS40 head which has a smaller chamber) which makes the power almost identical to the same engine running on 15% Nitro/Glow fuel. For those curious it turns a 10X7 15,100 on gasoline and before anyone chastises me for the high rpm's understand I am a pylon racer at heart and love hearing em scream. I also need to add the 15,100 is not with the stock muffler and the port timing has been altered as well. I changed the throttle barrel slot angle just slightly for improved transition and midrange and that's the only mod to the carb. It ran OK before the slot mod but is as smooth in transition as any factory gasser after the mod. As w8ye mentioned above the carb is quite sensitive to adjust and probably isn't good for those who are not extremely good at tuning but it can be done. With all that said I will add the SuperTigres have a little finer thread on the main needle than some others and that helps with the sensitivity on adjustment which is one of the reasons I chose to try ST for my first conversion. Good luck with yours if you decide to give it a try.