[Nonfractal]

It's been a while since I updated this thread with new Info. But a recent question (in another thread) prompted me to revisit this subject 
Slot racing and tuning is a learning curve that never flattens out 

Reviewing the GasMonkey team chat log from the 2022 24 hour Derby LeMans oxigen event, I was reminded of this gearing issue.
   

The monkey  yellow scaleauto corvette suffered multiple pinion failures during the 24 hours. 
This is a slot.it ergal 6.5mm 14 tooth that was being used to drive a nylon anglewinder and you can see that the pinion is splintered.
Surprisingly, the nylon spur was not damaged in the same way.

You can see on the tooth profile that the pinion has more teeth than the diameter of the gear would ideally allow.
For sprint racing, the compromise would be a acceptable. For 24 hour racing, it proved catastrophic.

For 14 tooth, the ideal diameter to preserve the perfect modulus  is 8mm.
A complete rethink of suitable gearing will have to be done prior to the next event. 

AlanW