I'm tired of listening to the rattling spark arrestor. Does anybody offer a shim to place to tighten this thing up? I like to be able to place this shim between the spark arrestor and the snap ring that holds it in. The dimension of the shim is about 1 5/8" O.D. by 1 1/8" I.D.; thickness would vary, I'm sure. Next issue. Front brakes are "spongy", and no amount of bleeding them has alleviated the problem. Ideas? (I completely flush the system with new DOT 4 brake fluid).