Is this your Router?
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If so, then I think maybe you are trying to get the machine to perform way higher than it was designed to do and you may stumble upon problem after problem, in your quest.
Just something to be aware of. I hope this is not the case for you.
Motor appears to get its power via the control board? I assume this means its a PWM signal to enable speed control of the motor.....You may have to find a way to get a speed signal from your board to another high power speed controller and use a external 24v DC power supply to power the motor.
You will have to do reach on the board to see if there is such an output you can use.
See how it gets messy pretty quick?
I'm speculating so I may wrong with all this...just thinking out loud.
Steve