There's a product called Bar Snake which adds damping mass to the handlebars. They're pretty effective. You can also try different weight bar ends. Try heavier ones to see if they help.
Bar Snake is better.
Back in the old days we'd pack the handlebars with lead shot and modeling clay and then plug the ends.
Bar Snake is better.
Back in the old days we'd pack the handlebars with lead shot and modeling clay and then plug the ends.