Large Caster Tires Radius models are equipped with large front caster tires. 13 x 6.5 pneumatic tires come standard on 48", 52", and 60" models and 13 x 5.0-6 on the 44" model. Powered by Exmark Engine Equipped with Exmark’s commercial-grade 24.5-horsepower 708cc V-Twin engine that features a dual barrel carburetor, cast iron cylinder liners and a quick oil drain hose raises the bar for productivity, durability and value. (Not available in California.) UltraCut Deck Technology Exmark’s exclusive UltraCut decks are featured on Radius models in a choice of 44- to 60-inch cut widths. Every UltraCut cutting deck features Exmark’s exclusive maintenance-free, sealed-bearing spindle assemblies for increased durability and reduced downtime, combined with zero maintenance.