The use of a 7/8” keyed shaft for an electric drive predates ME1616 by decades.? Several of the currently available motors not only spec’d that shaft size/style but also mounting hole pattern which was used well before this with the Briggs and Stratton (circa 2000 thru 2006?) ETEK brush motor (which I still use now 21 years later).? And even those B&S motors were stemming off the hole patterns and shaft size/style commonly used by Advanced DC Motors---the 1^st motor I used when I converted my outboard to electric in early 2003 was a surplus “ex-Tropica EV” motor made by Advanced DC Motors.? I was very pleased later that year when I learned that the ETEK permag brushmotor was rated at higher continuous output, much higher efficiency (cooler), was 40# lighter and smaller and used the exact same mounting hole pattern and shaft size/style as the ADC motors.? These ADC motors date back to the 90’s or earlier.? So it’s nicely been a common pattern to work with for sub-15kw or so power levels.

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