The hairspray thing is an old dirt bike trick I learned from a neighbor of mine. To take off the grips, use a thin bladed screwdriver to lift the grip. Squirt some hairspray in the gap. Twist the grip and off it comes. Use the hairspray again when fitting the new grips. When wet it acts as a lubricant but it dries like glue. Couldn't be easier...

-brent