A UNIVERSAL motor is OK to drive a compressor to pumpup one soft tire. The compressors that I have seen tend to get hot inflating one 78R15 tire. Not burning out hot, but rated temperature rise hot. Other folks may see different temperature ises.

 

I would typically use an unloaded method, where there is either a manual valve or auto means of doing this,
What kind of reduction do you have between motor and compressor?
What is the nature of the compressor, Piston? Vane etc?
Post Photo?

CERTAINLY there is a need to unload the compressor prior to attempting a start. That is not even a nnegotiable option. A possible alternative is a slightly oversized three-phase motor.

 

I personnally would never use a Universal motor for a compressor, unless the compressor itself could be ran at extremely high RPM??!
Even then, really a fixed RPM motor should be used.IMO.

 

I TOTALLY AGREE with Max!!

 

Another option not yet mentioned is a mechanical interface such as a centrifugal clutch, or a fluid drive coupling clutch. You would need to write a very detailed description of the performance, torque delivered versus RPM, but that is just creative writing.
The simpler choice is a commercialy available variable speed drive with a programmable accelleration profile. You can get as gentle a start as you want.