Ok compared to all these other people I can tune quite well, and can prove it. Ive got a webra 120 that went through eight owners before i got my hands on it and tuned it right! It would idle fine, but when you would try to throttle up it would increase rpm's a but then drop dead! For me my low speed needle rarely called "MID RANGE NEEDLE VALVE!" was half a turn too lean. I strongly suggest you make an attempt to tune your low speed aka mid range needle while running the engine. I can all most guarantee you that this will solve your problem.