This past weekend we were having difficulty tuning an Webra 50 GT. It has the TNII carb. It keeps getting fat and dieing in the midrange at the crossover point for the needles. It idles great and has quick transition from Idle to WOT but at that particular point where the needles cross it starts to get fat and dies. This engine is two years old and has run well in the past. I am thinking I has something to do with the carb maybe the High or low speed needle might have been smushed. Any ideas would be appreciated.

More likely the spray bar has been flaired by the low speed needle. Try to lean the low speed needle by a half screw driver blade width at a time. Maybe you can get the mid range right before the low end goes TTOOOO lean.

Denis

Thanks, we will check the spray bar where the low speed goes in an see if it is flaired. We did not have any success this past weekend leaning the low speed. It got to lean to run at idle and still had that excessively rich spot in the midrange.

Sport 10,
Try a new hot glowplug like Enya3, OS-F. Good luck