No, it should take off without hesitation.

If the HSN is set correctly, you need to do a pinch test for the LSN and see which way (lean or rich) you're off - here's Traxxas' tuning guide - adjusting starts about 3/4 of the way down. Prob be best to reset both and follow their advice.

http://www.traxxas.com/support/kb_se...ghlight=tuning

These engines use small needle adjustments cause they're sensitive. If you're turning needle 1/2t, you'll never get it set right. I did mine in 1hr increments (think clockface). The other tip - wait til engine is at temp before doing any, adj one needle at a time and run long enough after adj to understand what it did or did not do.