A regular breast collar harness can work with a sulky. A harness that is used with a sulky is typically a racing harness. I would strongly discourage you from starting a horse in a sulky. They are a rough ride, you need super strong stomach muscles to hold your position, you end up hanging on their mouths and they're easy to tip over. With no back on the seat to brace against, you can flip out the back, they are harder to get in and out of gracefully and you can't see over your horse.
Last edited by Left Hand Percherons; 06-27-2013 at 02:10 AM.