I use automotive trim panel removers. they use these in automotive body shops to remove the interior trim and plastic in the car without scratching the panels. also works great for removing bicycle tires. I used them half a dozen times on my tires so far with no problems. they are super tough plastic and almost impossible to bend or break.

they come in a five piece set. the three wider ones work the best for removing bicycle tires. their size and width gives you a lot of leverage which makes it easier to get the tire off.

http://www.amazon.com/Astro-Pneumati...s=trim+remover