Hi Russ,
I am running Lipos in my jet drive build and they are fine, the big problem I am having at the moment is with motor selection, as I am relatively new to brushless motors, I am finding the selection process to be a tad confusing. I am making my own jet units based upon the same Graupner ones you have, these units operate around 18-20K RPM, so I have been making my motor and battery voltage choice accordingly, 17-1800KV on 3s, tests with a watt meter on the lake are showing horrifying current draws at full power though, full power cruise is 100A, where as half throttle cruise is 30A.
This is the part that confuses me, to obtain the motor's peak power rating, I need to up the voltage to 6s, but won't also double the RPM? or am I missing something fundamental here?
Alex