Can you reuse handlebar grips?
Grab the grip and pull it off the end of the handlebar. Reusing the same grips can be done in one of two ways..if the grip is really tight going back on and does not need to be glued in place, just wet the inside of the grip with water and slide it on the bar.
Can you cut bike grips?
but yes, you can cut bmx grips. they even make bmx grips that are made to be cut down to whatever size you want.