In preparation to start designing the 84 pitch pinion trees, I bought a few extra "oval racer sized" sets and put them in our web store.




84 pitch (84P) pinion/spur gears were released last year, but this is the first time they've been available large enough for oval racers. 84 pitch gears provide 2 slight advantages over 64P gears:

  1. They are a little more efficient due to the decreased angle of attack on the teeth. You can feel the difference when comparing rolling 84P gears together versus 64P gears. The 84P gears are much smoother.
  2. Secondly, when you make a single tooth pinion change, it's a smaller rollout change. This let's you fine tune the rollout a little better.

These are surprisingly less prone to stripping than you'd think because there are 2-3 teeth touching at all times. At IIC in Las Vegas this year, even some 1/12th open mod cars were using them, so they can handle the powerful motors.
The pinion gear set is a set of 19 pinions: 74T-92T (55-68T 64P equivalent)

The spur gears are:
148T (approximately 112T 64P equivalent)
150T (approximately 114T 64P equivalent)
152T (approximately 115T 64P equivalent)
154T (approximately 117T 64P equivalent)