The TRX motors some can be touchy when it comes to a good tune. sometimes you have to just bearly move the needle on way or another to get it good. There was a couple people on here that are correct when it comes to the trans. Do not adjust the trans until you get an established tune, because when that tune is good the trans will shift when its suppose to. I have had 3 tmaxxes so far and delt with all kinds of mishaps. I currently have a Picco P-3 on my maxx. But for a 50F you should be close to about 200F. if your tipping over 240F then you need to richin her up abit. you will know when you have it right when you hit the throttle and there is and instant burst of acceleration and no lag. when you have that thats when you tune to performance with the high speed needle. Get that little stream of blue smoke coming out and your golden.

Good Luck

Anymore questions feel free to ask.