The engine has had a few tankfuls and flights before the conversion.Easy backflip starting and great idle.

I tried running on gas initially- Engine was difficult to start, so I retarded the ignition a bit and resorted to using a starter. Engine started, ran alright but down on rpm.I had 3 runs, First run neoprene melted while using muffler pressure. Subsequent 2 runs had the engine overheating. I can only guess that engines run hotter on gas and as tank level goes down the engine will run a bit lean as theres no pressure feed. RPM was about 6500rpm.How do you detect detonation- throwing props or pinging sound like frying eggs?

Changed the plumbing and switched to 7% nitro glow fuel. This time the engine was easier to start but even with timing advanced, I could only get 6800rpm tops.

Finally, took out the ignition and ran glow. Rpm this time was 8450, what a difference! and idling was good.

I can only surmise that you need pressure of some sort to run reliably. The 2 needle carb is not ideal for gas use as the fuel/air ratio is not consistent for the whole range and could be a fire hazard as there was substantial spitting at low idle. Just my views,could be wrong.A walbro is the way to go.


That said, it was a good experience, yes fuel flow seems to be lower using ignition and the sound was like a staccato bark, very pleasant and unique.