Google it and you will have your answers. Been attempted in many different ways.
When I first laid eyes on my CX650E it looked like it had been ridden hard and put away wet. No seat just the pan, no plastic body panels, dented rusty tank with no cap...
I stood staring at it with a frown on my face while the owner fiddled with a car battery and 1 LB. propane cylinder.
He hooked the battery up with one jumper cable, grounding the other terminal to the frame and hooked the propane tank to a valve and rubber hose, the end of which he poked into the air intake for the air cleaner.
On went the(propane) gas valve, cranking took about 10 seconds and it purred to life.
I was reaching for my wallet before I knew what I was doing
It WILL run for sure,just not sure how well.