I recently bought a tire changing and balancer package so I can mount my own motorcycle tires...specifically my car tires. I've never balanced tires before so I thought for added insurance I'd get a set of Centramatic wheel balancers. Everyone that buys them seems to like them. I bought them from Wingstuff.com.
There are two for the front wheel and one for the rear. On the front you remove the rotor and install the balancers between the wheel and rotors.
The rear one just slips over the wheel studs. Simple again.
I took the bike for a test ride to Shoals down SR450. I could easily tell a difference. The bike rode a lot smoother. There was a lot less vibration in the handlebars. Some people describe it as a gyroscopic smoothness and I understand what they mean.
Update: When I had a flat tire on our Georgia trip the Honda tech didn't even balance the replacement tire since I had the balancer on there. It rode fine with just the balancer.