Hey guys. I have a T-rex 500 all stock. Recently I bought two lipo 2600 6s 40c's, but have been flying 4400 5s 40c's. .. Here is the issue, the 6s seems to have a higher head speed, it's actually squirrely, and after 4 minutes the moter begins to surg,, you can hear it and see the effects of the head speed going up and down. It's done it with both batteries and now it does it even with the 5s batteries,,all after about four minutes. This nearly caused a crash. The 4400's would fly 9 minutes beforehand. Does this seem to be perhaps the esc going ape? Anyone had this up and down surging of the moter before.?
