Tuning an OS 50

[Ivan]

Got an OS 50, te SX-H, the older one that is not the hyper. It has the 2 needle carb, and I have to have the idle almost completely leaned out to get it to idle right. If I pinch the line the engine slowly picks up and takes around 20 seconds to die, so I would still call it rich.

Any ideas?

Thanks
Ivan

[Dan Lewis]

My os 50's have always idled rich but run well that way once the main needle takes over. I sometimes pinch the line before walking out to fly so it doesn't die on the way.