Running Ego and Ttech

Hi,

I've just recently got the Ttech system and am trying to run it with an ego. My problem is that the machine seems underpowered and I'm having to run it at 9v just to get it started, sometimes it doesn't start, even at 9v. Does anyone have any tips on getting this to work better as I'm afraid I'm going to burn the motor out. It heats up quickly and has a slight smell of burning engine, like after a few rounds of scalextric. How high is safe for me to run at as I feel I need more power. Thanks.