I am not sure if this was a Harley-Davidson Wall of tribal knowledge or something from Ron Kwas. In either case I have not done it as i do not have the equipment nor experience in welding. Here it goes.

Take a nut that is slightly smaller than the diameter than the bolt. For some reason the author stated that he doesn't clean the nuts and for him they are usually rusty. Whether this helps or not i do not know. He then states to weld up the inside of the nut thus forming a bond between the broken bolt and the nut. Then take your box wrench and go to town. It was noted that sometimes you won't get a good weld. Unfortunately I do not remember if he was Mig welding or stick. If need be i could research this some more.

There are also shops that will burn out the bolt material. A shop in gardena, California specializes in bolt extraction

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