I have a TT pro 46 with about 3 tanks through it. I can get it to idle at 2500 or so but it is REALLY rough. At about 1/4 to 1/3 throttle it smoothes out real nice. Is this because it needs more break-in or is it something else? (and how long should it be run before I can expect it to be smooth?) My OS 25FP idles smoothly but I got it used and I don't remember the ST 40 I had a while back ever idling like that.

Thnx,
Brian

It seems to me like your idle is set way too rich. With the engine running at idle try pinching the fuel line near the carburetor and hear what the engine does. If the engine stops sharply, you are running lean and you should richen low end. If your engine runs relatively long and picks up speed too much, you are running rich and you should lean low end.

Hope this helps.

I would let it run through another tank or two and then start adjusting the low-end needle. Turn it in at 1/8 of a turn at a time until it gets smoother.