Fairing Mount Bolt Snapped Off In Head

Have you used penetrating oil? Not WD40 (it's really a water dispersant, though it often helps), but proper penetrating oil. Put loads on and leave it overnight. You can even mould a little reservoir out of plasticene (or whatever) to feed oil into the threads...

A trick to try is to use a red-hot poker (not the plant) to apply very localised heat to the bolt in place. Sometimes it helps.

Usually, just having the head off the bolt is enough to get it moving, as the tension is relieved. But this is probably stuck due to dissimilar metal corrosion (steel bolt in alloy) which can be a right PITA.

Good luck!

 

^^^^^^^^What he said^^^^^^^

I use this:
http://www.ebay.co.uk/itm/SOUDAL-DE...hash=item20d0960ffd:m:mJzflfaGgcL8PdSJQ5OrunA

 

Get a drill with a left hand cut any good engineer supplier will have them, then tap the hole out, we do this all the time when studs snap in turbine housings. do not force the tap, if you snap it you're fucked!!

 

These mounts don't really have a head other than the end which isn't a head as such, about 5" from the thread - these threaded rods break really easily and god knows what sort of cheese they are made of.

There are two sizes of thread as well, one is M10 and the other is M8 IIRC, but the rods are the same diameter, so you can't teall what thread they are.

And yes, bust an extractor in there and it will need some hard work to get the whole lot out.

One way I got them out for a mate, was to dot punch all the way round the remaining bit, in from the thread itself and then use a 2mm drill
in all the dots; then I broke out the core of the 'stud' which allowed me room to use a very small chisel to collapse the bit left in the thread.

 

I had to drill out the front sprocket nut on my KTM Duke 2 when it snapped of just outside squires after a ride over from holmefirth . Pain in the arse but i just kept on going up drill sizes until i could peel out the remaining thread

 

You could try the dye penetrant used for crack detecting. It will wick into the threads & act as a lubricant. Much better than WD40 or similar lubes.
When you eventually get the snapped off bit out use something like Neverseeze on the threads of the new bolt.

 

Don't understand how m8 and m10 can be the same diameter.
Is that not an indication of diameter? Thread pitch fine or coarse?

 

As Arquebus said, the threads are different, but the actual rod diameter is the same.

 

So m8 and m10 can be the same diameter?

 

Twit - the rod is approx 10mm (possibly a bit larger) but the two threads are M10 and M8, so on one rod, it is necked down to 8mm - that's why the M8 one breaks more easily than the M10, but even then, by trying to undo thes damn things, you have to use the sort of head at the outer end, and then the whole rod is twisting, putting a load on the 'first' thread.

 

I'm slightly puzzled. The thread title refers to "bolt snapped off in head" but the photo clearly shows a problem area in the cylinder barrel, not the head. So which is it?

 

You could if very careful try the old small chisel end drift and the Irish screwdriver method of knocking round the edge of the remainder to see if it will come undone.

 

+1 on the left handed drill bit. Or just helicoil it, I had to do one too.