The best thing you can do is use heat before using a EZ out, I will first heat the broken bolt then use a LH drill bit and with luck that will be all you need and the bolt will come right out, if not heat it some more and try a EZ out' I just removed two 5mm bolts from a Marin frame this way, but the frame was steel and the paint wasn't the best, one bolt was on the seat tube ( Water bottle boss) and the other was on the rear brake bridge where a reflector mounted which is where I need to mount a fender bracket. I got the one on the seat tube out using my heat gun and the paint was fine, but the bolt on the brake bridge required the use of a pencil torch with a few cycles of heat then a cool down with penetrant before I got it out using a EZ out, then I primed & painted the brake bridge flat black and you can't tell unless you are looking for it..
Glenn
Last edited by Glennfordx4; 03-14-18 at 08:20 AM.