how many cells can i run?

[Patrick]

Higher kv motors (lower turns) have less torque than lower kv motors and generally draw more power (if everything thigh else in the setup is kept the same). They are more sensitive to changes in gearing than lower kv motors and everything usually runs hotter, because they draw so much power.
I burnt out 2 quarks using a 7xl on 14 and 12 cells and a lot of other people have had thermalling problems with them as well. A 6xl would cause even more heat issues.
Most people find it's better to use higher voltage and lower kv motors to get good speed and power with cooler, more reliable running.
My 7xl ran hot and so did the esc and batteries. Going to a neu 1515 2.5d (1700kv) and gearing up for speed actually had about the same performance, but cooler running. Now I run that motor on 5s lipo and have no heat issues, more performance and better runtime.