Exhaust stud challenge - solutions?

[drix]

Hi all

One of my exhaust studs snapped two years ago when I removed the old system for a 2-1 system. I finally decided to take on the repair and ditch the temp fix. Initial plan was to retap to M10 but failed in doing so and got the studs housing a little too big when drilling the old stud remnants out

The options I foresee are...

1. Welding a new M8 stud although not sure on welding alloy to what ever studs are made of though!?
2. An alloy filler that I could retap but which one?

Though or ideas are welcome as my knowledge in metals is pretty thin!

Cheers
Adrien

[alextrx850]

You've not too many options now Drix that will have the head still attached to the motor.
A photo would be an advantage although you might be a little shy...
Most likely, the head needs to come off and depending how bad , have a machine shop weld the hole and then re drill and thread,..I've seen helicoils done in the past, but that's mainly over size drilling and fitting a steel thread in...
It's the same problem of electrolysis and the salty roads you have there.
Mostly I would take the head off or maybe easier, take the bike and to an engineer as a proper fix is warranted.
Sorry, no easy fix now.

[Con Rod]

Cant you just drill out out and helicoil it?

[pbear62]

Helicoils are only really suitable as an actual 'thread repair' & if the hole is now too big they won't be any good.

Try & look for a product called 'keenserts' - these are an actual 'steel sleeve' - threaded inside & outside & a decent
thickness so you can use them in a larger diameter hole & re-use the original size stud.

Good luck. Andy

[Con Rod]

Helicoils are only really suitable as an actual 'thread repair' & if the hole is now too big they won't be any good.

Try & look for a product called 'keenserts' - these are an actual 'steel sleeve' - threaded inside & outside & a decent
thickness so you can use them in a larger diameter hole & re-use the original size stud.

Good luck. Andy

was thinking drill, tap to a larger thread and then use a helicoil, there is plenty of meat there.

On the plus side when you replace the lugs you can use stainless, which will make life easier in the future

[SDN]

I had this issue and made up a stepped stud 10mm one side 8mm the other, all with head in situ.

you have already drilled out 8.5mm for 10mm tap? Can you now get the broken stud out?

As has been said there is plenty of room so you could have a stepped stud 12mm on the engine side and 8mm on the exhaust side. Take a bit of 12mm stainless all thread and cut to length, turn one side down to 8mm and run a die down it - bingo.

[drix]

I've been able to get an M10 bolt in there and holding things in check! Should do for the summer hopefully but it's still not as clean as I want it to be!

Good set of options here to chose from will see what I want to do during next winter/if the fudge breaks before

P.S. Stud is out, will post a pic soon.

[Rich]

Look at Timeserts too

http://www.timesert.com/

will "fill" the hole better than helicoils, you can also get bigger inserts for when it is really buggered.

As said before a two diameter stud is an option and I personally would go for that, whether to make from stainless is debatable, if using the std header clamps (alloy) then I would keep to BZP steel and stick lots of copperslip on it, using brass nuts will also help.