I think the plastic motor mounts are better at absorbing vibrations that the aluminum ones but I could be wrong. I wonder about a solid wiece of rubber behing the mount cut to shape of mount. I recently took of a metal motor mount on a Ultra Stick that weighed 4oz and replaced it with a Dave Brown mound and save about 3oz. The Dave Brown mount weighed a little over 1oz. I wondered at the time about cutting a solid piec of rubber a bout 1/8" thick and sticking it behind the mount but I decided I didn't have a piece that I knew would resist the fuel. Any thought on this idea