Not sure why you would want to narrow your bars, but I can for sure tell you to NOT cut the hand warmers. That will make them not work anymore. You can if you are VERY careful heat them up with a blow dryer/heat gun etc, peel them off gently and re-apply them, sometimes I put some electrical tape around the ends and once in the middle upon re-applying. Again though with how narrow these bars are stock, imo I would not cut them, it will not benefit you when charging thru any sort of chop or cruddy conditions.