I can't seem to get the 60mm 2000kv to run cool on 5s (pushing 190+), but on 4s, geared 15/50 the buggy rocks. Still a bit warmer than I like, 170 ish, but my timing is at Low (5), will set it to Lowest (0) and try again. 100% punch control, lowest start power setting, some curve in the throttle.