I have a 1992 yamaha virago 1100. my headlights and turn signals work fine but no parking lights

Start with checking your fuses, if all three running lights are not working (front two and rear running/brake) then it should be power related. if your fuse is ok check you bulbs, it's ez and quick.
if you haven't found your power it's time to get out the test light. Start at the fuse block and work way to the lights when loss power you found your problem. If your fuse is blown we now that something made it blow, replace the bulb (if one is blown) and turn on the bike with a new fuse, if blows test for ground on the power wire this the bike off. a multimeter on the ohm setting is the easiest way to do this. now this can take a bit it there is a short in the wire take your time and you'll do fine.
M.Woodring