Nah. Just fill them up till they're over the fins. Can lay the bike a little to each side, but generally just start the bike with the cap off to start with. It might spit out an air bubble. Top up over the fins again. Check for leaks.
Cool- thanks. I didn't think there could be more to it than that. I put new rads on both sides and it took a little less than a half gallon of coolant. Now to get it to idle again...
