I currently have a gravely pro turn 152 with the Kohler EFI engine. I have explored the option of running propane in the past but it seems the mowers that are ready to go from the factory are expensive or they only offer 60+ inch decks. Bobcat does have the predator-pro in a 52in that's propane but that looks like it.
Does anyone have experience running propane? I've been told that generally $20 or so will cut about 40 (1/2 acre or under) properties and they run very clean compared to a gasoline powered mower.