Originally Posted by
Crankycrank
Hard plastic grips may come off with some heat from a hairdryer or pour boiling water over them. Heat also helps to soften up most adhesives.
When I replace motorcycle handlebars, I just dip the left one into a glass of boiling water for a few minutes to soften it up, then pull it off by hand.
(The righthand grip unbolts with the throttle mechanism.)