I have a Speed Passion Low Profile Speed control and a 10.5 Brushless to put in my l4 12th scale. There is no way the sensor cable will reach the speed control where I have to mount it. Does anyone know if the motor can run without it or should I figure a way to lengthen it?

There is no way it will run without a sensor wire you are going to have to make it longer to reach.

Just lengthen the sensor wire.

Cut it somewhere in the middle, Get some hookup wire the same gauge, Solder and shrinkwrap each individual wire, Then shrink the lot with some larger shrinkwrap.