Quote:double up on the rubber pads for additional damping. (part #15 @ $4/ea)
I think those suckers are actually plastic, but it's been a while since I took the bars off. I do remember however, looking at them pretty closely, thinking that rubber would work better (especially if it was thicker) and wound up ruling that out with the stock bolts.
Maybe I'll just take the bars off, dip the open ends in melted lead, and reassemble. There's got to be something that actually dampens the vibes.