Get hot.....No brakes!

[rcjmaxx]

I've got a TXT-1 monster truck with a 9L/9918 combo,the truck weighs 14lbs with 14 cells and geared 65t spur 16t pinion for topspeed running.Recently after 3 passes the controller temp hit 170 and it had no brakes,after slowing down reverse is there but still no brakes.Because the batteries were dead I called it quits.The next day before taking it out I reprogramed the controller,and everything was back to normal.But once the controller hit 165 degrees again no brakes.After cooling down I drove it and had brakes again.Throughout all this the truck never thermaled.Is this odd? Are these temps TOO high for this controller? Thanks for any info.