Wow, He can check for arcing while he goes down the track.
My first thought, (having blown up a commutator), was he needs a scatter
shield! But then I realized it might be darn near impossible to hit 5000rpm
~4:1 rear means that would be 1250rpm and on a 24" wheel that is
14rpm/mph or 89mph, oh!! no so hard. What is that thing geared at?
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