These might help - http://www.scottsperformance.com/indexframe.html#accessories.htm
"Bar Mount Replacement Cones: If you have rubber mounting cones in your triple clamps, i.e. KDX, KX's, CR500's, have you ever noticed how your bars flex and mis-align easily. Scotts now offers a set of high density replacement cones made from Sanaprene thermal plastic elastomer. These act and feel like rubber but are far superior. They replace the stock rubber cones that allow your handlebars to flex and even appear to be bent. Scotts replacement cones incorporate an injection molded aluminum top washer, which eliminates all the top-hat washers that come with your stock units. Made for KDX, KX, and CR's that use rubber mounted perches these replacements are 30% more dense so they still allow good vibration absorption but won't allow the mis-alignment and "over-flexing" found with the stock units. Price: $19.95"