I was told that if the basket was "imbalanced", that it would cause vibration. Well, for 2 years now my bike has had a bad vibration under hard acceleration........right at 5-6K RPM. And nothing has cured it.........not carb syncs, not valve adjustments, not bolt torquing, and not chains/sprockets. So what else is left? Do you think it could indeed be the basket? How much do those things cost?