You should use a relay, if you didn't already.
That wire you used behind the side cover would be a good choice to drive the relay, but not your
lights directly... here's the wiring diagram I used recently to install my driving lights...

If you view the diagram image directly it might look bigger (it is plenty big to see all the detail), the VRCC site
scales images to fit on the page...
I used the blue wire going to the headlight to drive my relay (the "any wire with power when the ignition
is on" wire) so my lights only come on when the high beams are on... you'd probably want to use the
wire behind the side cover instead...

There's a lot of good Valkyrie specific wiring diagrams at rattlebars.com, and they have a picture
that totally demystifies relays if you need it (it really helped me with the first accessory I hooked
to my Valkyrie)...
-Mike