Riding with broken exhaust stud?

[JackDG]

Replacing the headers on my 02 cbr, and I have snapped 2 of the studs already (both on the same pipe).

It also appears somone has previously installed BOLTS instead of the usual stud / nut arrangement, which im assuming is not helping the issue.

Either way I have 2 broke studs. I'm going to spend a few days applying penetrating oil to the bolts and giving it another go hopefully after this has had time to set.

In the mean time, is it safe to ride? doesn't seem to be any leak as im assuming the fact they snapped the bolts are still stuck in place so nothing is 'loose'
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1992 GPZ 500

[Easy-X]

As you ride the vibrations will work stuff loose and you might get an exhaust leak. Congratulations! you're hastening the planet to its doom with your irresponsible ways

Seriously though, if nothing's about to fall off it's all good. Sooner rather than later fixing it would be better ofc!
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[JackDG]

[JackDG]

I was hoping after several days of spraying down with penetrating oil, some of the bolts may loosen up.

If not, they are breaking right at the head, so that the remaining bolt is flush with the exhaust header collars. Worst case, if every bolt broke at the head (looks like it may), would the exhaust be able to just slip off over the bolts as im assuming the collar is not threaded?

This would then give me bolts sticking out of the engine which I could then try to remove. Can't really see any way about it. The bolt heads themselves were so corroded it took a good while with carb cleaner and wire brush just to be able to fit the socket over it
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1992 GPZ 500

[Easy-X]

Any chance of a photo of this debacle? Might help
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Robby]

You'll probably end up having to drill out the stubs. Get some cobalt drill bits, its likely they're stainless bolts and normal drill bits won't get through them without making a mess.

Replace them with mild steel studs and brass bolts. The mild steel studs are less likely to snap. The brass bolts will round off before breaking the stud when you go to remove them in a few years.

[JackDG]

Photos attached. You can see the two bolts on top side which have snapped perfectly flush to the collar. If I end up breaking all of them in a similar fashion, the exhaust will simply pull away right????

At which point I can follow your advice robby. 2nd pic shows the sheared bolt heads.

https://i.imgur.com/Wp786zl.jpg
https://i.imgur.com/HQRQzfT.jpg[/img][/list]
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1992 GPZ 500

[Riejufixing]

If they're seized into the steel flange, as they look, you'll have to do a lot of tap tap wiggle wiggle to free the flanges off when the bolt heads/stud nuts are off, trying not to distort the metal, possibly using a drift. Yes the flanges should slide off if the bolt heads are removed, the studs aren't normally withdrawn after all. You might be able to use the time-honoured technique of loosening everything off that will loosen and running it for a while with loose nuts, the rest might vibrate free. IF there's room for a nut splitter that's a useful way to loosen the stud nuts (you can also support the nuts on the "far" side with a piece of steel while you tap a sharpened cold chisel in). You don't have to split the nuts completely, just make sure the distortion opens theit inside diameter a fraction.

[Grubscrew]

Should be straightforward to wind two nuts on the remaining stud and lock them together tight, heat the ally spigot the stud is in with a plumbers torch and it will undo with a spanner on the nut closer to the head.
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FJR1300/CBR1000F

[stinkwheel]

The best thing to do with that once you have the collar off is to weld a nut to the end of the stud (or get someone else to do it). The heat generated will free it off and it should just undo.

It would be easy to do now, it would be harder to do later with less stuff sticking out.

Although in fairness, the standard studs on a CBR6 aren't much better. In their wisdom, Honda made up special studs with an M8 thread going into the head and an M7 on the other end. Almost like they were designed to snap exactly flush with the head.

The previous owner probably decided to change the exhaust and threw away the nasty rusty nuts before realising they were an oddball thread size.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[kramdra]

Run engine HOT before any further attempts. The thread will expand, allowing siezed bolt to come out with less force. Heating the bolt directly has the opposite effect, and it gets thermal shock every day in normal use.

Alum is a safe, but slow way of removing snapped bolts in an alu head. Its slow and requires heat.

[Riejufixing]

I still think the bolts (& studs) have fused (rusted) to the flanges. When iron rusts the rust occupies a much larger volume than the original metal, and if confined it generates huge forces leading to seizure of components. I hope the OP posts an account of how he fixes this problem.

[JackDG]

Got a hold of some map gas, and managed to remove 2 bolts fully intact.

Off came the headers, leaving behind 6 studs to remove . Got a laser brand stud extractor - basically a drill chuck with a 1/2 inch driver so you can grip and turn the stud. With heat and a lot of penetrating oil I got 4 of them off without too much struggle, but they were seriously corroded in there. Also appears some of them had been heli coiled previously.

But now I have 2 flush snap studs on different ports tho.

What's the go to route here? I'd be happy to pay to have someone experienced drill them out or weld a nut on the end or something. I'd be even happier to just ignore 2 studs and install new headers but I'm not sure how well it would seal/crush the gasket??
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1992 GPZ 500

[WD Forte]

I'd tack nuts on them too, as Stinkwheel said, they usually come out nicely and it's usually the least stressful and further phuckup free method.
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bikers smell of wee

[Easy-X]

If you've got this far you may as well do the job right even if that means giving the job to someone else. The bike's machine soul deserves no less
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Pete.]

[JackDG]

I think you guys are correct, going to find some way of tacking on a nut and backing it out.

Cheers all
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1992 GPZ 500

[Pete.]

Snapped flush studs I'd put a thick washer over the hole and weld the stud to the washer, then weld a nut to the washer, then turn the nut to un-do. If that doesn't work, drill them out. Get a bit of thick flat plate and drill two holes in it exactly the distance of the studs apart. One is a clearance hole to fix the plate to the port. The other is a smaller hole, say 5mm, to act as a drilling guide. Bolt the plate over the port and use the guide to drill the seized bolt.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[JackDG]

[stinkwheel]

[JackDG]

[JackDG]

https://www.youtube.com/watch?v=VtiaI74Loq8

The method in this video is similar to stud extractor, but tapping in a torx bolt instead. I suppose the idea is they are more resistant to snapping than an extractor. I'd be more comfortable drilling a shallow hole for this as opposed to drilling the whole thing out.

Couple garages near me claimed there are oilways at risk near the threads (02 cbr fsport), 1 doesn't want the job and the other has a 3 week wait list but he still wasn't confident 'desperately hateful job' to quote him .

I'm also gonna use way more heat then I first did. Will update how I get on.
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1992 GPZ 500

[Pete.]

[JackDG]

next to milton keynes.

Happy to pay fairly if you / anyone else is near by!
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1992 GPZ 500