I am having a problem with the carb settings on my BME 115. When I set the needles for a good transition after a 30 second warm up. I cannot fly in a knife edge from right to left only, left to right is o.k. This is at half throttle or less. Above half throttle is o.k. I can fix it by leaning the low end but then it is too lean for a good transition. If I hold the plane on the ground in this same atttitude with the cowl off, fuel comes out of the carb and the engine smokes so I know it is going rich. I have tried a line of the carb plate to the fuse, and a 3W 90 degree intake. I can't see it being an airflow issue if it is doing on the ground with the cowl off.