Grab it real good with your hand and twist. Their friction fit and they pop right off. Hell my thottle side came off while I was riding, right in my hand. Surprise... Just installed my new Kury Flame grips that I got from Directlineparts and man what a difference it makes in the overall look of the bike. Took about 1/2 hour to install. Don't have pics yet.
A screwdriver will get the ends off. If you need to take off the entire grip and preserve it, you can take an air compressor (if you have one) and just lift up the edge and blow air into it and continue that around the entire grip. It will separate the grip from the bar and should slide off. But, if you're going this far, you should just consider putting on some nice aftermarket grips. In this case, you can just cut the factory grips off with a single edge razor. :bigthumbsup: