Do I need to use a relay for a upgraded horn?

[flw]

I have a Kawasaki Vulcan 500 LTD '07. It does not have the capability for many electrical accessories (unused stator capacity). So for a upgrade to a air horn that pulls 10 plus amps it is suggested to use a relay.

My question is since it is wired to the battery and uses a inline fuse, what does the relay do/purpose in this application?

The directions I'm getting from Paul Andersons page at http://en500.us/horn.html .

Thanks for helping fill in my holes of electical understanding.

[daddymakk]

while I can't say for sure with your bike, I did add an electric air horn to my 1250 Bandit and used the factory connections. It works fine. The only side effect I've noticed is a dimming of the headlights when I use it because of its draw. Kind makes them flash if you use short bursts which works great for deer fixated on a light. I think you'd have to hold it down for some time before over loading it....but that's just me.