Removed exhaust and in the process one of the nuts was frozen onto the stud so I wound up backing out the stud with the nut on it. Got new stud and this is where I need guidance.
I figured that when I started screwing the new stud in, that it would eventually hit bottom and stop. But that doesnt happen, stud seems to want to screw in as far as you will let it.
So I backed it out to proper length, hooked up exhaust, put the nut on it, and started to tighten it down. The nut didnt go on very far before nut and stud started turning together. It does tighten down adequately, but the nut isnt on the stud very far and Im concerned that it will be easy for the nut to back off.
Any tips on how to keep the stud from turning as i tighten?

 

A little high temp JB weld. Just enough to keep it in place. Or high temp loctite.

 

I do not believe you have correct parts or when your stud backed out it was because if it's a 2012 and has not been apart before the original threads were damaged or tapped oversize. The correct stud is a double end class 3 on one end and an oversize (to correct size) for a class 5 interference fit so it does not come out. The nut should be a harden lock type nut. Loctite and such will not work in the heat range of the stud exhaust area. Even if you get it from a dealer make sure he looks it up and gets correct part number. Not in his generic bolt drawer. The correct stud will take a stud driver or two nuts locked together to screw it in. I guess it is possible when nut got frozen and screwed stud out, it could have stuck (galled) and striped threads out coming out.

 

It is a 2012 Ultra classic. thanks to both of you

 

Just to make sure, when I look at my studs, one side of the stud is longer than the other. The shorter side has finer threads and the longer side has coarser threads, So the short side goes in the head and the longer side is the one you put the nut on?
sorry to be a dipshxt.

 

Most threads that go in to aluminum have coarse threads do to the soft metal. Did you look at the other stud? The nut is fine threads.

 

Never crossed my mind you would have turned it around. When you screwed proper end into hole was it tight going in or did it just depend on bottoming to tighten up?

 

The stud you are using should be 5/16"-18 on the end that goes into the head and the other end that receives the nut should be 5/16"-24. Pretty simple to check the depth of the thread boss in the head and compare to the lengthe of the 5/16"-18 end of the stud. If not, get another stud.

Loose head studs usually indicate that there is a problem with the threads. So, you need to check that out as well. Get a 5/16"-18 bolt long enough to thread in and hit bottom. As you thread the bolt in, grab the head and see how much movement there is with the bolt in the thread bore. You may need to drill the thread boss over size and use an insert to restore the threads.

I would not use Loctite or JB weld; a loose stud is a much easier problem to deal with than a stud that has broken off in the head. Might as well be thorough and find a permanent solution so you won't have to deal with this in the future. JMHO.