K bikes already have horn relays, so you should be good. I'd bump the horn and cooling fan fuse up to 30 amps, though. I had to hit the horn (stebel nautilus, modified for a remote pump) while running hard (95mph) in 100 degree weather. Cooling fan must have been on, so it honked, and then stopped, and I started getting the coolant light when I would wind up to pass.
