Originally Posted by
ezlight
For those that are running 13.5 class with your XB4, what are you running for gearing? I've searched, and seen most are dropping their spur gears down a few teeth. Is this 100% necessary? Can you reach good gearing & speed with the stock spur? If it matters, I have a 2014 xb4. And have a speed passion 13.5 motor I'm throwing in to try the class out.
I don't run 13.5 in wheeler but I run 17.5 in 2wd buggy and usually you can get the same or nearly the same gear ratios with the larger spur, but going to the smaller one will change motor position. so you could get the motor a little closer to the center of the chassis with the smaller spur, since balance and weight is more critical with 17.5 & 13.5 classes.