I had already imported the damn headers from the US (astronomical postage!) before I found out the bad news...... also

 

Well between work and other **** getting in the way, a friend was persuaded to call down with his welding kit. Got the 3 studs on one side out within 15 mins. But the other 3 had other ideas. They ended up snapping. The next day i got the bolt extractor kit. 1st stud i started the pilot hole on, Bam. Drill bit snapped. So i had to leave it or i would have set fire to the bike then and there! Hopefully i can get a few hours at it during the week!

 

Yeah, sometimes the best thing is just to walk away, before you do something you'll regret later

Hope you have better luck on the next attempt.

 

Yes. Once there's no more thread left with the nuts and lock nuts method your going to need these.
You'll need a panel pin hammer and a sharp hard chisel. A heavy hammer will NOT do.
Don't angle the chisel too flat and now tap ....tap .....tap...your going to be a while. Adding lots of heat to this would be nice. Don't get carried away and try to smash it off, that's not how this method works.
Best of luck

 

I had a pretty radical idea when I had the two studs snap on me. I thought of buying new studs and cutting them and welding them onto the broken studs. I proposed this to the welder but he said this would need an accurate weld so has to be TIG and would need the head on a bench. But I think if the broken stud is ground off close to the head-not all the way flush with the head, but to the point where it starts tapering out and then the rest of the stud welded cleanly(may be even mig by someone having steady hands) to it so that the bead is strong but not big?
Thankfully for me the weld a nut and unwind method worked and I didn't have to try the above