crt.5 velenion cutting out

[mxsxwannabe]

I put my crt together velenion combo, 5000 2s lipo, stock spur 13t pinion. It will run for about 30 seconds well, then it goes to about half power then no power. Im wondering if it's because of my gearing. The cutoff voltage prompt keeps going on......? The battery has a full charge. I only want to run it on a track so I really want to keep it geared for 2s.