Help! My simple exhaust removal was not so simple (surprise)
Discussion
I knew it wouldn't be a simple job, but when the first 2 bolts came out quite easily with the help of a blowtorch and release spray I started to hope.
It's a 2003 CBR600F4i and at some point someone has replaced the studs with stainless bolts. That and the apparent lack of gasket could explain why my exhaust was blowing. My issue is that the socket cap bolts are so rusted and worn that there's no purchase on them and even hammering a torx bit in gave me no luck.
I tried drilling the heads off, but even with a ryobi power drill I didn't seem to be making any progress (they're clearly not cheap bolts).
I managed to use an angle grinder (cutting disc followed by flap disc) to get one bolt out after removing the adjacent downpipe, but I'm really struggling for access to the others, even with the radiator off.
Does anyone have any advice to get these damned things off so I can finally ride my bike I've been fixing for a year?
It's a 2003 CBR600F4i and at some point someone has replaced the studs with stainless bolts. That and the apparent lack of gasket could explain why my exhaust was blowing. My issue is that the socket cap bolts are so rusted and worn that there's no purchase on them and even hammering a torx bit in gave me no luck.
I tried drilling the heads off, but even with a ryobi power drill I didn't seem to be making any progress (they're clearly not cheap bolts).
I managed to use an angle grinder (cutting disc followed by flap disc) to get one bolt out after removing the adjacent downpipe, but I'm really struggling for access to the others, even with the radiator off.
Does anyone have any advice to get these damned things off so I can finally ride my bike I've been fixing for a year?
Edited by Bl0ndie on Monday 11th July 10:26
The genius replaced the studs with bolts eh? Great.
If you've not already I'd look at removing the radiator and anything else that's in the way.
Then I'd try a bolt and nut extractor on an extension like this;
https://www.ebay.de/itm/165425357129?mkevt=1&m...
(At work so German link, but you get the picture).
If that doesn't work, I'd cut the heads off. You should then (hopefully) have enough metal to use a roller type stud extractor;
https://www.amazon.com/Extractor-Roller-Remover-Re...
Then budget a full set of studs and bolts, personally I then added copper grease, but that does increase the risk of things rattling loose. I also spray with penetrating oil at every oil change.
That's what I did when I did mine on the 99 CBR anyway.
I've no experience of welding things, perhaps that's easier.
If you've not already I'd look at removing the radiator and anything else that's in the way.
Then I'd try a bolt and nut extractor on an extension like this;
https://www.ebay.de/itm/165425357129?mkevt=1&m...
(At work so German link, but you get the picture).
If that doesn't work, I'd cut the heads off. You should then (hopefully) have enough metal to use a roller type stud extractor;
https://www.amazon.com/Extractor-Roller-Remover-Re...
Then budget a full set of studs and bolts, personally I then added copper grease, but that does increase the risk of things rattling loose. I also spray with penetrating oil at every oil change.
That's what I did when I did mine on the 99 CBR anyway.
I've no experience of welding things, perhaps that's easier.
steveo3002 said:
find someone with a welder and burn a nut on there on the hottest setting ...give the head a whack with a hammer and pray it comes undone
This is the best way imho! The heat and a good new head on it will help massively. You could also get someone with a MIG but use stainless wire.Also, not sure how much a set of downpipes would be 2nd hand, but I'd consider cutting the current ones off for access, then replace.
Krikkit said:
Also, not sure how much a set of downpipes would be 2nd hand, but I'd consider cutting the current ones off for access, then replace.
No need to damage the pipes.Once the bolt heads (which should be studs and nuts) are off, the pipes will slide over the studs, that's when you can get the roller type stud extractors on there.
Or weld to the studs, whatever works best.
Prof Prolapse said:
No need to damage the pipes.
Once the bolt heads (which should be studs and nuts) are off, the pipes will slide over the studs, that's when you can get the roller type stud extractors on there.
Or weld to the studs, whatever works best.
OP says the pipes have been put on with stainless bolts, not stud and nuts
Once the bolt heads (which should be studs and nuts) are off, the pipes will slide over the studs, that's when you can get the roller type stud extractors on there.
Or weld to the studs, whatever works best.
OP says the pipes have been put on with stainless bolts, not stud and nuts
Krikkit said:
Prof Prolapse said:
No need to damage the pipes.
Once the bolt heads (which should be studs and nuts) are off, the pipes will slide over the studs, that's when you can get the roller type stud extractors on there.
Or weld to the studs, whatever works best.
OP says the pipes have been put on with stainless bolts, not stud and nuts Once the bolt heads (which should be studs and nuts) are off, the pipes will slide over the studs, that's when you can get the roller type stud extractors on there.
Or weld to the studs, whatever works best.
Yes, I understand bolts have been used. But after you cut the head off a bolt, I would say you are left with a "stud".
You can then extract this.
In any eventuality, once the bolt head is removed, the the exhaust mount will slide over the remaining thread length. There's no need to start hacking at the exhaust, but you might need a cutting tool to get the bolt head off.
Similar to others recommendations really, I'd just add to use good quality cobalt drill bits, Milwaukee DeWalt Makita etc, usually a few quid per bit. Slow speed in bursts to keep the bit from cooking, I'd highly recommend cutting oil too, just a drop acts like grinding paste and speeds up the bit cutting. Failing that, welding a nut on the head is the next thing. Depending on access I've used small pipe grips before too on allen bolts. Get some stainless studs and dome nuts to replace them, you'll never have the same headache again
A bit off topic but given the OP will need to replace the fasteners whichever way he goes....
Years ago I had a car that needed frequent attention to awkward exhaust studs. We had steel studs and brass nuts. Never corroded at all. I think the different expansion rates helped keep the manifolds tighter too possibly. Why don't bikes have brass nuts on the exhaust studs...is it just cost/availability or is there a more fundamental reason?
At some point no doubt I'll have to remove the studs/bolts on my bike so I'm asking now to be ready for later....
Years ago I had a car that needed frequent attention to awkward exhaust studs. We had steel studs and brass nuts. Never corroded at all. I think the different expansion rates helped keep the manifolds tighter too possibly. Why don't bikes have brass nuts on the exhaust studs...is it just cost/availability or is there a more fundamental reason?
At some point no doubt I'll have to remove the studs/bolts on my bike so I'm asking now to be ready for later....
stang65 said:
A bit off topic but given the OP will need to replace the fasteners whichever way he goes....
Years ago I had a car that needed frequent attention to awkward exhaust studs. We had steel studs and brass nuts. Never corroded at all. I think the different expansion rates helped keep the manifolds tighter too possibly. Why don't bikes have brass nuts on the exhaust studs...is it just cost/availability or is there a more fundamental reason?
At some point no doubt I'll have to remove the studs/bolts on my bike so I'm asking now to be ready for later....
I think my KTM690 has brass nuts on the exhaust. Years ago I had a car that needed frequent attention to awkward exhaust studs. We had steel studs and brass nuts. Never corroded at all. I think the different expansion rates helped keep the manifolds tighter too possibly. Why don't bikes have brass nuts on the exhaust studs...is it just cost/availability or is there a more fundamental reason?
At some point no doubt I'll have to remove the studs/bolts on my bike so I'm asking now to be ready for later....
Biker 1 said:
stang65 said:
A bit off topic but given the OP will need to replace the fasteners whichever way he goes....
Years ago I had a car that needed frequent attention to awkward exhaust studs. We had steel studs and brass nuts. Never corroded at all. I think the different expansion rates helped keep the manifolds tighter too possibly. Why don't bikes have brass nuts on the exhaust studs...is it just cost/availability or is there a more fundamental reason?
At some point no doubt I'll have to remove the studs/bolts on my bike so I'm asking now to be ready for later....
I think my KTM690 has brass nuts on the exhaust. Years ago I had a car that needed frequent attention to awkward exhaust studs. We had steel studs and brass nuts. Never corroded at all. I think the different expansion rates helped keep the manifolds tighter too possibly. Why don't bikes have brass nuts on the exhaust studs...is it just cost/availability or is there a more fundamental reason?
At some point no doubt I'll have to remove the studs/bolts on my bike so I'm asking now to be ready for later....
Thanks for the suggestions everyone, I've been struggling to find time to tinker on the bike due to the weather in the UK and having a 6 month old to keep entertained. Thought I'd add a resolution for any future people with the same problem. Welding would have been the easiest, unfortunately I only have access to an ARC welder which would not have helped at all.
I borrowed a Dremel from a friend, which was able to fit in where the angle grinder couldn't. Used a 409 attachment to cut through (540 worked very well too, but was quite thick compared to the 409). Then I used a grinding attachment to get the last bits out the way to remove the collar and get the downpipes out the way.
I now have something resembling a 'stud' to remove, but the threads are so rusted and worn that the handy 'two nut method' of removal woudn't work. I've ordered an impact stud removal tool and am intermitently applying heat and penetrating fluid to the studs until it arrives. Fingers crossed they come out okay and I can put the new studs in with a liberal application of copper grease.
I borrowed a Dremel from a friend, which was able to fit in where the angle grinder couldn't. Used a 409 attachment to cut through (540 worked very well too, but was quite thick compared to the 409). Then I used a grinding attachment to get the last bits out the way to remove the collar and get the downpipes out the way.
I now have something resembling a 'stud' to remove, but the threads are so rusted and worn that the handy 'two nut method' of removal woudn't work. I've ordered an impact stud removal tool and am intermitently applying heat and penetrating fluid to the studs until it arrives. Fingers crossed they come out okay and I can put the new studs in with a liberal application of copper grease.
OutInTheShed said:
Tig weld a nut on works.
I think there are chemical methods, not sure if alum works on stainless?
Drill the bolt out and clean up with a tap?
Spark eroder.
Has anyone who suggests welding a nut on actually tried it ? It doesn't work.(particularly as he has bolts not studs) There is only one way, and that is drill with tungsten carbide drill bit. I bought my set 15 years ago. Most often the engine needs to be out to drill straight. Start with 2mm then bigger, untill you have a tiny bit of thread left. I've done replacement broken exhaust studs many many times. One of the biggest pain in the bum jobs on a bike. I think there are chemical methods, not sure if alum works on stainless?
Drill the bolt out and clean up with a tap?
Spark eroder.
Edited by fred bloggs on Tuesday 19th July 15:17
fred bloggs said:
Has anyone who suggests welding a nut on actually tried it ? It doesn't work.(particularly as he has bolts not studs) There is only one way, and that is drill with tungsten carbide drill bit. I bought my set 15 years ago. Most often the engine needs to be out to drill straight. Start with 2mm then bigger, untill you have a tiny bit of thread left. I've done replacement broken exhaust studs many many times. One of the biggest pain in the bum jobs on a bike.
I had the idea of ceramic coating the downpipes on my bike black to look a bit smarter (and I hate cleaning them), the guy at the garage I spoke to about it said pretty much the same as you that's it's such a ballache of a job it's not worth the hassle.fred bloggs said:
Has anyone who suggests welding a nut on actually tried it ? It doesn't work.(particularly as he has bolts not studs)
Yes, have had success with MIG and arc removing bolts and studs. The key is to get a good pool of weld going inside the nut, and penetrating it of course, then making sure it's completely cold before you try undoing it.Last time it was removing a 3mm bolt which had snapped below the surface on a cylinder head.
As long as it's steel I wouldn't even try and drill it out these days.
Gassing Station | Biker Banter | Top of Page | What's New | My Stuff