Topic: Best way to loosen and fasten 6mm nuts and leave the studs alone

[Deltarider]

Many of you that have removed the headers, will recognise the problem. When you unscrew the 6mm nuts, there's the risk the dito studs will turn too and on fastening there's always a chance the thread in the head turns out to be damaged. The last time I had to removed my exhausts, it was my turn. Three of the eight studs gave problems. A friend, who had every reason to be grateful btw, helped me solve it. He, a yacht mechanic, preferred to use Timesert, which is indeed a great invention. The question remains: is there a way to avoid as much as possible such a repair, in other words is there a trick on loosening/fastening these 6mm nuts? Is it better to do on a cold engine, or do you have a better chance when the engine is hot? What can one do to prevent future problems? Has any of you tried a slit in those studs, so in future you could use a screwdriver to keep it in position whilst undoing the nut ?

[kerryb]

I have reduced the incidence of this problem by cleaning the exposed threads with a wire brush, spraying with my favorite penetrating oil, and cleaning the threads again before trying to loosen them.  Haven't had a stud problem on the last three old bikes I worked on.

[bryanj]

In 40+ years i have not found avsolution to this. If the stud undcrews put it in the vice and warm up the nut to remove, double nut the stud to refit with nothing in the way after thoughroughly cleaning the threads then coat with antisieze before fitting new nut and tightening. If you can get brass nuts to replace the originals they usualy do not sieze to the steel.

[DaveBarbier]

Not sure if there’s enough stud to do this, but you can try to put two more nuts on the end of the stud and ‘double nut them’ then try and break the original one free while holding the double nut.

Or use vise grips on the end of the stud with aluminum or copper soft jaws?

If the stud does come out you can use high temp red Loctite 272.

[Deltarider]

Thanks gentlemen. I'm afraid I did not understand what Calj ment in reply #5.
The problem I had, is that the thread in the head is very, very easily damaged. Timesert proved very useful. Guy that did the job, now has the vacuum gauge set i never used.

[754]

 I would not say they are easily damaged.
 The whole idea of a stud though, is to prevent problems with threading in and out.
 So red lictite and you should be good.. but on a 750, its easier to remove motor with a few studs pulled out.

[754]

I use vise or pliers with aluminum shim for padding to grip the studs.
A proper stud has an unthreaded are for this.
 If you are not using proper studs, then it may he part of the problem. Reddi Rod is not a good fit.