Thanks Bob, My Kohler is 13 hp, with a 5" pulley.
I called Woodmizer this morning to ask what the rpms is on the 10 hp electric that they show on their site. And even though he was in parts department, it didn't show in his computer, so he couldn't tell me anything, even how much it weighed.
I did go ahead and picked up the motor this morning, with the understanding that I could return it if I can't make it work. Now that I have it to measure, I can see how it can be mounted closer toward the drive side, since it is narrower than the gas engine, which will allow me to use at least an 8" pulley on the motor, without making any modification to the housing.
And if I chose to cut the little housing cap part off above the drive belt, then fabricate a taller one, I could go on up to a 10" to get the same fpm to the blade.
I'd still like to hear from anyone using an electric motor what theirs is. Or even anyone running gas or diesel with a tachometer, what are your rpms when under load. I don't have a tac, but just go by ear to determine feed rate, striving to make a decent size chip, without overloading the motor, so I know my gas engine isn't running at full rpms, but I don't know how much lower.