Took my old 2 wheel trailing sulky and made it into a castering sulky. It has 8" tires. The platform sits alittle high but it works very well and it surprised me how little it affects the mower on hills. It takes some getting used to after switching from trailing sulky but I'm adjusting already. I also welded a stub pipe on the foot platform which lets me put another pipe on that one and a bicycle seat on that pipe. Now it's a walk behind, stand on, or rider you can also just stand with the seat still on.