If you can't get an idle below 2800 then there is clearly somerhing wrong with the fuel system setup, or the engine is not broken in, or the carb is not assembled correctly. My chinese 2300s idle well at 21-2200 with a 17-6 or 17-8 prop. Trying to get an idle down to below 2000 is interesting but I see no reason for this, although if you fly from a paved runway that may be a factor. for that you may need to go to apc or similar props which are heavier.

Also, if your engine is an Italian made 2300 it may have a carb problem. Some here have reported problems with the Italian made 2300 carbs. however, I have no problems with tuning the Chinese made 2300 carbs after the engine is broken in as long as the muffler has sufficient back pressure. When the super tiger factory was moved to china the new owners redesigned the carb, I understand. So the carbs on the Chinese made 2300s are a different design from the I talian made 2300s. I wll add that I have never run an Italian made 2300 so this reported tuning problem may just be the same back pressure/adjustment problem as the reported problems with the Chinese made 2300s.

If your 2300 is putting out a lot of unburned fuel then the carb is too rich. My 2300s put out very little unburned fuel. They do need to be be run fairly rich during breakin with a fairly high idle (about 300 rpm or so) until the ring fully seats, but after that they run best tuned to be not overly rich so they do not put out a lot of unburned fuel. In fact my 2300s put out alot less unburned fuel than the equivalent Saitos that the guys run at my field.

Another thing to consider is the glow plug. you should be using a fox rc long or os f plug, at least in the chises 2300s. the super tiger plug is worthless. As far as I know the italian made 2300s were designed for the same compression, porting, etc as the chinese 2300s, so the glow plug comment should apply there also. Other glow plugs may have the wrong heat range. Also, older glow plugs may no longer have the correct material properties to properly make the fuel light off - there is a catalytic action of the glow plug with the fuel and if the plug is old it may not do this properly any more.

Ed