Finally located the noise I would get cruising between 5 and 30 mph (foot off the gas). I got tired of listening to it so after work I crawled under and hit everything. When I hit the gas tank I heard that sound but it wasn`t coming from the tank. I saw the right rear spring vibrating like a tuning fork so I hit the tank again only this time I grabbed the spring and no sound. I hit the coil spring with my palms and there it is. It seems like there is a space between the coil and the upper seat. I removed the stock internal bump stops a while back but I remember that it was making that sound with it on. Anyone know of a good rubber isolation pad made for this ?