Any bright ideas?

[Miztaziggy]

At the end of last year, my brother and I managed to shear the bleed nipples on both his front brake calipers while trying to bleed the brakes.

They both sheared off while trying to tighten them, luckily at the time, they were in far enough that brake fluid wasn't coming out.

So now I'm trying to get them out and replace them.

They both sheared the little bolt on top, leaving a little hole visible where the oil would normally come from.

I put a screw / stud extractor in the hole and tightened. It got to the point I couldn't tighten any more and it kept slipping in the tool.

I took it out then tried the next size up, that one didn't screw in as far, but sheared in the hole. I've tried drilling the stud remover but it's very very hard and the drills get nowhere.

Now I'm left with this, so, any ideas on how this can now be removed?:

Before:


After:

[tony.mon]

A centrepunch will loosen the broken bit of stud extractor, and then you can drill the sheared-off bit out.
Ideally, buy a left-handed drill bit. As the heat from the drill bit builds it sometimes simply locks and undoes the section of nipple.
If not, you can then try a larger broken stud extractor, which is less likely to break.

And don't use aluminium or Ti bleed nipples next time!

[Pete.L]

As far as I'm aware You can't drill an easy out. You can grind it weld it or smash it and hope it shatters they are so hard.
Should have drilled the nipple out and used a helicoil but it's too late for that now.
Can you take the Pistons out and get at the nipple with a centre punch from the inside?


Sent from my iPhone using Tapatalk

[Watty]

Spark erosion will sort that but it'll cost more than the caliper is worth unfortunately!!

[Miztaziggy]

A centrepunch will loosen the broken bit of stud extractor, and then you can drill the sheared-off bit out.
Ideally, buy a left-handed drill bit. As the heat from the drill bit builds it sometimes simply locks and undoes the section of nipple.
If not, you can then try a larger broken stud extractor, which is less likely to break.

And don't use aluminium or Ti bleed nipples next time!

Tried this, it just blunted and then broke my drills. Bugger.

Spark erosion will sort that but it'll cost more than the caliper is worth unfortunately!!

Yeah I read about this. Sounds good, but expensive.

As far as I'm aware You can't drill an easy out. You can grind it weld it or smash it and hope it shatters they are so hard.
Should have drilled the nipple out and used a helicoil but it's too late for that now.
Can you take the Pistons out and get at the nipple with a centre punch from the inside?


Sent from my iPhone using Tapatalk

After some more reading, sounds like I need to be using Carbide drill bits rather than HSS, shame left hand ones are in HSS.
I've just ordered some Carbide bits to see if they work. If not, it's new caliper time.
I don't think I can get to it from the inside, it's at a funny angle.

There's also this:


Not got great reviews though, apparently it's expensive for what is basically a carbide drill / burr / end mill all in one.

[sirch345]

Good luck with it, but a 2nd hand replacement caliper could be your best option. Even that tool in your video link is not cheap,

Chris.

[cheekykev]

After some more reading, sounds like I need to be using Carbide drill bits rather than HSS, shame left hand ones are in HSS.
I've just ordered some Carbide bits to see if they work.

Why bother trying to buy left handed Carbide or HSS, just buy normal handed drills and re-grind them the opposite way, It's not difficult, I've done it loads of times, All you have to do is re-grind the cutting edge and re-grind the rake the other way round from normal, I'm sure if you can't do it you'll know someone who can do it for you, after all you only need a grinder.
Some heat might help you to soften the stud extractor, if you know anyone with a Tig welding set, they can put a very small tungsten tip in, say 1.00mm or 1.5mm and heat it up for you using low amps so it only heats it up and doesn't try to weld it, worth a try
By the way what is the original material of the damaged bleed nipple
Without seeing it it's difficult to say, but another possibility is use a dremel or a grinder with a fine cutting disc and cut a slot in the top, bit like a screw driver head slot, yes you might cut the ally as well, but does that matter, then you can use a impact driver, if that doesn't work you should be able to punch it round using the sides of the slot

[Stephan]

I know bleed nipple is more difficult, but what about common screw extractor?

edit: it seems you´ve tried it already ...

[budd]

if you find it can't be removed why not try a pair of these :
http://www.ebay.co.uk/itm/like/13134803 ... ue&ff13=80

it allows you to bleed the brakes via the hose banjo bolt, it will do the job and will save you having to replace the caliper.

[ConTRo13R]

The banjo isn't at the top of the caliper like the bleed screw, so you may still end up with air trapped at the top.

[Dendrob]

My bro had his rgv250 calipers recon' by an outfit he'd talked to at the classic bike show and they did a first class job. Better than new. They do a service exchange service too and maybe if you were open with them they might have a solution? Worth a shot to ask.

If you're going to try to get the thing out the only way I can think of (I'm not a qualified mechanic btw) is to use a slender centre pop and "drift" it out. Applying a torque and shock load together in other words. First I'd strip it down to bare caliper minus any rubber parts and soak the area in plus gas a few times.

If it isn't passing brake fluid as it is and you fancy just leaving it, maybe it would "bleed" just using gravity, but you'd have to suss what position would allow the air to rise and find its way out and leave it suspended for a while . I mean with the hose and master cyl connected and filled with fluid. Whenever I've refilled rear caliper set ups I've taken this approach as they can be a swine to bleed. It's always worked for me.

Best of luck whatever route you go.

[tony.mon]

Hang on, this seems like a lot of work.
I have a spare set of Storm calipers, if that's any use?
If that's easier (and avoiding machine shop charges) they might do you a turn. PM me if interested and we can sort out a price.

[budd]

The banjo isn't at the top of the caliper like the bleed screw, so you may still end up with air trapped at the top.

true but this isn't a problem you simply remove the calpier and position it so that the banjo mounted nipple is the highest point and bleed away the calpier doesn't need to be mounted to bleed it, the only way to bleed the rear brakes on my Aprilia is to remove the caliper and reposition as the OE bleed nipple is underneath so bleeding it in situ is impossible.