Mc 91 production year

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Mark Poos
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Vintage Karting items owned: Bug , Dart, margay expert
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Location: Gilbert Arizona

Mc 91 production year

Post by Mark Poos » Wed Mar 13, 2019 10:20 pm

wondering what year the Mac 91 came out and what year mine was produced . Looks to be all original, is that the original carb looks kind of big.. how many cc's were these. Around how many horsepower are they? And how many RPMs can I expect after it's been rebuilt?

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Re: Mc 91 production year

Post by REAR » Thu Mar 14, 2019 6:49 am


First series of 91's came out around 1966. Can't see the carb in your photo but they did have one big single from the factory.


Rob Voska
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Re: Mc 91 production year

Post by Rob Voska » Thu Mar 14, 2019 9:00 pm

Beware! Iif it's the early straight bore without a venturi they are not very desirable & lean out a lot on high end.
Not sure but I was told they didn't pull well off the bottom either. They were quickly replaced.

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