I was thinking about trying the 17t pinion gear and the 64t pinion gear that the Yeti and the Bomber use. That was i should be able to achieve more torque and less speed which is what i'm after right now. In fact the Yeti uses a 16t pinion and a 64t spur so the 17t pinion is pretty close. Have you read those two articles of Axial (http://www.axialracing.com/blog_posts/1073910694 and http://www.axialracing.com/blog_posts/1073921336)? This line "Again, bigger pinion, more speed. Smaller spur, more speed." explains it all i think It basically means that if we use a smaller pinion and a bigger spur we will achieve less speed and more torque. I still don't understand why can't we fit a 16t pinion in there or something smaller. Could it be because of the motor's shaft? Because the mount isn't even the same diameter as the gear.