Hello bmclaurin,
Most motors are going to reach between 130-160F.
My Scorpions get up to 180, I've seen some other brands reach over 200F.
I would not start worrying about temps until you reach the 180F mark.
You can also give Mike Donovan a call at Aero-Model, he can give you specific temps the
Hacker 470kv motor can withstand. At IRCHA last year I tried a 580kv motor in my E7 with
the 12T pinion. Temps were between 185-190, I ran it like this for 3 months with no problems.
I eventually took to motor out to test another motor.
Thanks,
Matt