I just picked up the ST. 90 at my LHS,

Any advice or tips/tricks for getting my ST .90 tuned up before I try it....

How many tanks should I run through it on the ground.

Thanks,

Michael

How many tankfulls? Well, I do mine for 30 minutes worth of break in time. (running rich, but not 4stroking) Make sure you follow the manual closely.

What plane is this going in?

Extra 300S .60 size

I have a new G 90 and I run 3 tank of 14 oz in ground, 2 tank 14 oz flying with rich fuel and now i try to have the uper RPM and 2 or 4 clik back the "aguja""nail?" of the carburator.

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Sergio

Michael, set the needle valves as per the instructions. Around 2 out on the low and 3 out from the bottom on the high end. Get it started and running. You want to run it very rich at first. The ST 90 is ringed so running slobbering rich is good. Let it run in 5 minuit intervals for the first 2 to 3 tankfulls. Cooling completely between runs. Then run it at low to medium rpm's for several more tankfulls slobbering rich. For the next 2 to 4 tank fulls start to lean it out. Untill you get it running decent. You may need to work the low speed needle some here. Remember, the engine runs on the low speed needle till after half to 2/3rds throttle. after this proceedure it should be ok to fly as long as you keep it rich. Ringed engines usually take quite a while to brak in. Don't be surprized if it takes a gallon or more to be fully broken in.

Just take your time. Break it in accordeing to the instructions. My suggestions are guidelines, not holey writ. The ST will treat you well. Mine have, good luck with your ST.

Mark Shuman

Thanks,

I will follow instructions.

Seems like S-T's require a bit more breaking in than other engines, but it's well worth it. I'm in the same boat as you, I have a fairly new g-90 to tune, although mine has been sitting on the nose of an airplane for several years without being run.

Andy