XRAY - Model racing cars

Hi guys,

I have super awesome XB4 it is very beautifull,well made model and i like it more than rest of my auto's, but i can't resolve one problem and hope you can help me Here's the situation - this year i'm racing in beginner class. Here we are allowed to use three motors - LRP S10 blast (20500rpm), LRP S10 twister (23500rpm) and thrust eco 21 (25500rpm). I've tried all of them, but no matter what i'm having SERIOUS heat problems - after 5 min run all motors are well beyond 110 degrees (celsius), and after 7 minute final runs S10 reaches 150 on brushes and thrust eco just melts inside.....I've tried different gearing - 81T spur with 25T pinion. Also 74T spur with 25T and 27T - last combo (74/27) is somewhat competitive in terms of speed, but motors are smoking after first qualification. The only gearing that keeps temps reasonable (by that i mean ~80 degrees) is 74/22, but in this gearing i loose waaay too much speed - all the LRP blast models are faster in straight lines and what i gain in perfecting my turns, i keep loosing in straights. We are running big tracks (indoor clay and outdoor clay/sand) initially made for 1/8 nitro buggy, so straights are long enough to loose 1-2 positions each time. I was starting to think XB4 is not made for beginner race (i know, it's mod), but guy in same class races kyosho and his temps are normal, so i know i'm doing something wrong myself.
Any ideas would be appreciated.

Well,
1.You could download from here:http://www.teamxray.com/xb4/downloads/xb4_2016_set_up-sheet_CARPET.jpg
Try pinions less 20T.

I'm not familiar with those motors, so forgive me if I'm way off base here.
Have you asked the Kyosho driver what his final drive ratio is? If not, ask and see if you can find a similar ratio for the XB4. You also haven't mentioned if you are using any timing advance or boost. And of course, be sure you have no binding in the drive train or gear mesh.

Good luck
Darryl

I would stick to the stock 81 spur. Not for sure on the pinion. I remember running stock truck years ago with similar results. Getting beat that way was discouraging. I found out they had a few tricks to improve performance. One thing that was already mentioned was the timing. Advance the timing for more rpm=mph. Be careful, the magic stops if you over heat. Sounds like you know what that's like. Other than that , the thing that always worked for me was to dedicate a practice session with successful racers and hope they help figure it out. Hope this helps.