i think there's a tendency to do this at first with a new setup,while you revel in the new found power,i do it anyway.i think it will be fine in normal running though if you are running it up and down at WOT for 10 mins to hit 130F.Try driving it with a little sympathy for a pack,still plenty of WOT,and see what temps you're getting.
130 is a bit warm for the batteries, but not too terrible. I would be sure to let them rest/cool before running them again, though. You are drawing on the batts pretty good to get them that warm. Possibly a drop ingearing would spare them some agony and allow them to last longer. You could also add two cells and drop a couple teeth on the pinion. You would get similar speed, more power, longer runtimes and cooler batteries.