I regularly change motorcycle tires for many folks and average 10 tires a week. I use a Coats 220 tire changer. Not to dismiss the balance beads, but you might look into a wheel balancer from Marc Parnes (
http://www.marcparnes.com). What I use is somewhat different but these work well. Using something like this allows you to check a wheel for out of round, out of balance and things like that. You will get your money back many times with this simple purchase. I purchase lead weights from an auto parts store (NAPA) along with tire changing lube to help with the bead. Typically I put the wheel on the balancer and mark the heavy spot with a grease pencil, then mount the tire aligning the manufacturers dot (lightest point of the tire) to my mark. Very often the heaviest part of the wheel is not at the valve stem. Most of the modern tires are made so well, in most cases I am balancing the wheel and not the tire.
There is a limit to how close you really need to balance a tire. The racers I change tires for are really picky and tell me they can sense a tire out of balance when running 180 mph (290 kph) and above. For us more normal humans, it is really difficult to tell when a tire is out of balance.
Here is an old tip in balancing tires. If the tire requires a lot of weight, try breaking the bead and rotating the tire 180 degrees. Many times that will result in a lot less weight, or possibly none.
Using a tire balancer has proven to me the uselessness of the BMW spoke rims. I've never seen a round or true rim on a spoked wheel unless they have been specially aligned by a professional shop. Sorry, but I'll stick with the alloy rims, but I don't consider a GS to be an off road machine either.