Originally Posted by aeRayls
Going with a 16 pinion is the wrong way. A single wind motor is all torque and needs a taller gear. The 87 is never necessary for the B4, 84 at most. Start with the 81 and a 21 pinion. You should be able to go clear up to a 23 and be just fine in racing conditions.
My bad. somewhere along the way I thought you were running a T4, not a B4. Gearing is definitely higher in the buggy due to the smaller wheels. I run a 23 or 24T pinion with a spec motor in my B4 while truck pinions are always in the teens. Sorry if I mislead you B4wires.
I still stand by my recommendation with single wind motors, they need lower gearing than double winds to make usable low end in my experience.