How to remove broken stud that has broken bit inside?

Here is a good question. I took this bike to have a broken stud drilled out and the guy tells me that someone else had already tried to drill out this stud and must have broken a bit off inside. He said that I would need to take it to a machine shop where they would basically burn it out. He said I would have to remove the head or take the engine out to do this.
Is there any trick to doing this without having to go through all of that?
I was looking forward to getting it done and riding it this weekend. I would greatly appreciate anyone's valuable feedback as I have never dealt with this before. I did read a post by Jeff at Z1 that said that those mac headers were good for this kind of trouble.

is it an exhuast stud?can you use a harder slightly smaller left handed bit to turn it out?

Is it broken off flush or is some of the stud sticking out? Maybe (a big maybe) you could use a dremel cutting wheel to cut what's left of the stud out of the way so you can get a pair of vise grips on the bit.(?) Just a thought.

Back when freon was cheap, I was able to extract a couple of broken bolts, by freezing the broken bit and shattering it. A center punch in my air hammer worked nicely. Once the broken bit was out of the way I could remove the remains of the busted bolt.

If you know of anyone with a welder I've removed many broken studs by welding a nut on the end.
Just removed a carb holder bolt that broke this way.
The heat also helps unstick it (probably why it broke originally).
Not sure if the broken bit already in there would hinder welding.

The bolt broke off inside the hole and there must be about 3mm inside. The dremel sounds like a great idea. I read somewhere about a diamond drill bit attached to a dremel. That is is harder than the hardened drill bit so it would work for cutting out the drill bit. I have cutting wheels unfortunately nothing was sticking out. I tried to drill a hole but it wasn't happening.

diamond is not going to cut the steel, the only real option is to have a shop with a EDM burn it out, or try to break the bit out of the stud by hand, you will propbably make a mess out of it before it shatters since the stud is way softer than the drill, and chances are the guy who attempted to drill it out has made a mess to start with

I like enormiss's idea. I had to use this method on about 6 exhaust studs on a 650 head. If there is still some stud coming out of the head this is the best method IMO.

jordan wrote:

I like enormiss's idea. I had to use this method on about 6 exhaust studs on a 650 head. If there is still some stud coming out of the head this is the best method IMO.

Only wish this were true but unfortuneately the stud broke off inside so I guess that rules out any chance of using that method.
So no diamond bit like I had read that would be a waste of time? I guess if I have nothing else to lose but pulling the head off and taking it in to the machine shop I might as well try it to see what happens.

Sorry you're having to do all that. With none of it sticking out, it sure reduces your options. I hope the machinist can fix it up for you. Good luck!

Well heck with it. I am going to try the idea of using a diamond drill bit and if it doesn't work then I guess I will pull the head but that seems like too much work when it doesn't need to come off until it needs to. The bike runs sweet doesn't smoke or nothin.

Use clay (modeling clay, play dough, etc) and build a pocket shaped dam around the hole, then mix up some alum and water into a thick slurry (thin enough to pour). Pour the alum slurry into the pocket you built up around the hole until the hole is filled. Let it sit overnight and see if there is anything left of the drill bit or the bolt. May have to do it twice to dissolve all the bolt.

Alum should be available where swimming pool supplies are sold.

Sounds crazy, don't it? It works and won't damage aluminum.