Pulling out a dent? Does it work/is it safe
#1
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Pulling out a dent? Does it work/is it safe
I'm looking at a bike that was dented but the guy said some bike mechanics drilled a couple small holes to pull it out, he sent a picture that I've attached. Any ideas if this is dangerous? It's a really good deal otherwise. Thanks for your input.
#2
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From: Columbus, OH
Bikes: '08 Surly Cross-Check, 2011 Redline Conquest Pro, 2012 Spesh FSR Comp EVO, 2015 Trek Domane 6.2 disc
Pulling out dents on a car panel is fine because it isn't load bearing. Doing the same on a load bearing structural member isn't such a hot idea.
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#4
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So essentially the frame could snap? I have and have had bikes with dings and kona is chromoly so I thought that it would be able to distribute weight around the damage. Is it worse because there are holes now? or is it that the ding finished the frame off in the first place.
#6
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as long as he welds the hole back up, it will be fine. cro mo is a little more tricky than mild steel. depending on how thin the tube is, he could have a tough time welding it closed without burning through.
just don't bondo the holes. they will shrink and crack eventually- look bad.
just don't bondo the holes. they will shrink and crack eventually- look bad.
#7
I would not ride that frame. I hope you didnt pay much for it -- sell it for scrap because it's garbage.
whoever these mechanics were, they're idiots. I actually doubt any bike mechanic would even consider drilling holes into a frame instead of just rolling out the tube with the proper tool - I think you have been lied to - the previous owner did it himself.
whoever these mechanics were, they're idiots. I actually doubt any bike mechanic would even consider drilling holes into a frame instead of just rolling out the tube with the proper tool - I think you have been lied to - the previous owner did it himself.
#9
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From: Saitama, Japan
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Reminder: a great number of frames have holes that size drilled in their downtubes as a matter of attaching cable stops with rivets.
What's the frame made out of? Also, what tube is it? Downtube? Top tube?
Frankly if it's steel I don't think it's an issue, whether the holes are filled again by welding or not.
What's the frame made out of? Also, what tube is it? Downtube? Top tube?
Frankly if it's steel I don't think it's an issue, whether the holes are filled again by welding or not.
#10
Reminder: a great number of frames have holes that size drilled in their downtubes as a matter of attaching cable stops with rivets.
What's the frame made out of? Also, what tube is it? Downtube? Top tube?
Frankly if it's steel I don't think it's an issue, whether the holes are filled again by welding or not.
What's the frame made out of? Also, what tube is it? Downtube? Top tube?
Frankly if it's steel I don't think it's an issue, whether the holes are filled again by welding or not.
and the holes that are drilled at tube intersections.
i don't know much about structures and framebuilding but it seems to me that that stuff is consistent with other normal things done to frames.
#11
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Bikes: Panasonic NJS Keirin x2, Level Professional, Bianchi CUSS, GT Pulse
I've never seen cable stops riveted to a frame; those are braze ons. I think sometimes they'll put a light rosette weld, but rivets?
And bottle holes are inherently different since the hole itself is reinforced by a threaded sleeve and a full weld around the circumference. Holes drilled at tube intersections are tiny and serve as vents to allow for the escape of accumulated welding gasses and drainage.
This particular frame has a bunch of indiscriminate holes in a concentrated area. Not to mention, the metal has been dented and reshaped, and this action alone is enough to reduce the integrity of the metal at that part of the tube.
And bottle holes are inherently different since the hole itself is reinforced by a threaded sleeve and a full weld around the circumference. Holes drilled at tube intersections are tiny and serve as vents to allow for the escape of accumulated welding gasses and drainage.
This particular frame has a bunch of indiscriminate holes in a concentrated area. Not to mention, the metal has been dented and reshaped, and this action alone is enough to reduce the integrity of the metal at that part of the tube.
#12
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Joined: Mar 2006
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From: Banned in DC
The frame will almost certainly crack at that location at some point, it might be in a few weeks or it could be 5 years from now. I would not pay a nickel for that frame, but if it were free I might ride it with a sleeve.
Remember that modern, high quality bicycle tubes have a wall thickness of .4-.6mm in the middle. That is the thickness of a couple pieces of paper.
Remember that modern, high quality bicycle tubes have a wall thickness of .4-.6mm in the middle. That is the thickness of a couple pieces of paper.
#13
Beausage is Beautiful

Joined: Oct 2003
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From: Saitama, Japan
Bikes: Nabiis Alchemy
I've never seen cable stops riveted to a frame; those are braze ons. I think sometimes they'll put a light rosette weld, but rivets?
And bottle holes are inherently different since the hole itself is reinforced by a threaded sleeve and a full weld around the circumference. Holes drilled at tube intersections are tiny and serve as vents to allow for the escape of accumulated welding gasses and drainage.
This particular frame has a bunch of indiscriminate holes in a concentrated area. Not to mention, the metal has been dented and reshaped, and this action alone is enough to reduce the integrity of the metal at that part of the tube.
And bottle holes are inherently different since the hole itself is reinforced by a threaded sleeve and a full weld around the circumference. Holes drilled at tube intersections are tiny and serve as vents to allow for the escape of accumulated welding gasses and drainage.
This particular frame has a bunch of indiscriminate holes in a concentrated area. Not to mention, the metal has been dented and reshaped, and this action alone is enough to reduce the integrity of the metal at that part of the tube.
You still don't know what the material is, whether it's TT or DT or whatever, what the tubeset is, etc. Way to conjecture.
#14
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From: Banned in DC
#17
My bicycle is fixed
Joined: Apr 2006
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From: Auckland, NZ
Bikes: '08 Surly Steamroller, '07 Surly Cross Check
Dents are not normal, and we have no information about the dent except that some idiot drilled holes into what was likely already a weakened part of the steel.
You might get a sweet price on that frame, but you might want to beef up your dental coverage while your at it.
#18
true, and i'm not arguing that the frame is fine. i'm saying that there's a big, salient difference between "we can't know if it's sound or not" and "it will fail and make you die three times, each time more horribly than the last, and also your loved ones are watching." it has to do with internet rumormongering.
#19
I would be more worried about the frame being significantly out of alignment due to the dent than the repair. I would speculate that the mechs were not pro's. A frame builder would press the dent out with blocks with half circles cut into them not by drilling and using a slide hammer.
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
#21
go ask an experienced framebuilder if it's a good idea to drill holes in your top tube for internal cable routing without any sort of reinforcement. he will tell you exactly why this is a bad idea which is also the same reason why this frame is garbage now.
you've offered bad advice and your participating in the "internet rumormongering" with this advice. the truth is this frame is damaged beyond repair and has the potential to fail and, therefore, is not safe to ride. No one can predict when the frame will fame (or if it will fail); all that is certain is the risk of frame failure increased exponentially once the idiot mechanics decided to drill holes into the frame instead of rolling out the dent.
#23
you're saying it's ok to drill holes into frames because it's "is consistent with other normal things done to frames" and the frame in question is fine to ride and those that question it's integrity are spreading irrational fears and rumors on the internet.
#24
Yah, and I qualified it by saying that I don't know anything about it.
I didn't say it was fine to ride.
Questioning its integrity is fine. Ignorant claims are not.
I know everybody likes to tell other people how they're wrong on the internet, but I think you're swinging and missing on this one.
I didn't say it was fine to ride.
Questioning its integrity is fine. Ignorant claims are not.
I know everybody likes to tell other people how they're wrong on the internet, but I think you're swinging and missing on this one.
#25
what claim have I made do you think is ignorant? how am I wrong?
seriously -- spend less time talking about something you [admittedly] know little about and go ask a framebuilder if it's ok to drill a top tube or seat tube without any sort of reinforcement.
seriously -- spend less time talking about something you [admittedly] know little about and go ask a framebuilder if it's ok to drill a top tube or seat tube without any sort of reinforcement.





