I think that only applies to full-frequency starting. If the frequency is near zero when the motor has to start, I think that a PMSM will be fine.Unless that is your only choice of a motor, or this is a"model" type/size kart, in my opinion your not going to like the end result. A PMSM of large enough size to move a kart with a person on board will also need a "starting motor" to get it to move.
Quote, " Above a certain size, synchronous motors are not self-starting motors. " From - https://en.wikipedia.org/wiki/Synchronous_motor
I think that only applies to full-frequency starting. If the frequency is near zero when the motor has to start, I think that a PMSM will be fine.
A BLDC motor has some sort of position feedback so needs to have a more complicated interface between the motor and the drive circuit, but may be a simpler driver circuit. A three-phase motor will work with just three wires, but the drive circuit may be more complicated.Then why don't the use them instead of the more common BLDC motors? Not trying to start a fight, but just to understand the thinking of this.
A normal stepper motor is a common type of permanent magnet synchronous motor, although named differently.