DEX210 RTR 10.5 Motor Gearing
 

I am going to replace my standard 13.5 brushless with a 10.5 turn for a little more go & would like a ball park idea on how many teeth I should change the pinion by, as standard the car runs 29/81 so would a 27 tooth pinion be a good starting point?

should be somewhere near, these two links are useful

http://teamnovak.com/tech_info/view_article/26

http://durangofansite.com/DEX210gearing.php#210

Excellent, I spent ages trying to think where I had seen the chart that is on the fan site. Many thanks

Equilivent to 29/87 I always found best with a 10.5 motor on a 210.

10.5T - 24/81 would be a good place to start. And change the pinion a tooth or two lower if the track is smaller. 24 is nice on a big outdoor track