ORIGINAL: bikermonkey
I don't know the stock esc number, but in the manuel it calls for a 22v 6s but I've been flying it for a year with 5s 18v getting 8 min flights,, so I''m thinking the esc could be the reason it's surging,, reving up and down after 4 minutes with all the batteries, it does not seem to be heating up. I thought of changing the throttle curve but that may fix the head speed but not the surgs... crazy man, crazy stuff.
It could very well be the ESC.
If you decide to replace it, Hobby King makes a good un unless you are independently wealthy (Like Simon)?
[link=http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=30930]Here![/link]
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