Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Failed derailleur hanger, damaged frame, restitution likely?

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Failed derailleur hanger, damaged frame, restitution likely?

Old 07-16-19, 06:22 AM
  #26  
Wilfred Laurier
Señor Member
 
Wilfred Laurier's Avatar
 
Join Date: Feb 2013
Posts: 5,064
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 648 Post(s)
Liked 290 Times in 214 Posts
Originally Posted by Marcus_Ti
So? They don't have everything. And the further back you go, the more hit-miss it is. Same as OEMs. Their cut off line seems to generally be about 2010-2011.

For example my 2002 BMW blue Kestrel Talon I have hanging up--I'm never finding an RD hanger for it again, in all honesty, should I ever have the urge to build that frameset up again.
I promise they have hangers for 7 year old Madones. All catalogued by frame make model and year. And, while I wouldn't be money on it, I would thing Trek does indeed still provide hangers for that bike.

Either way, 'Straightening' a hanger on a carbon bike is an unnecessary risk that the shop could have avoided by saying 'we dont' have a hanger, but we can get one."

I've been in this situation, where you try to do something out of the ordinary or cut corners because you don't want to have to tell a customer that their bike won't be ready today, or will be more expensive. You can generally get away with a kludge on a cheap bike, where a broken-hanger-caused scratch isn't the end of a frame.

I'm not saying it's entirely the shop's fault - maybe they told that OP's friend that he would have to wait, or that a new hanger was $50, and he complained. But hangers are definitely available, and the shop should know that, and that would have been the correct solution and would have avoided the problem.
Wilfred Laurier is offline  
Likes For Wilfred Laurier:
Old 07-16-19, 06:50 AM
  #27  
sdmc530
Heft On Wheels
 
sdmc530's Avatar
 
Join Date: Nov 2014
Location: South Dakota
Posts: 3,124

Bikes: Specialized,Cannondale,Argon 18

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 887 Post(s)
Liked 560 Times in 346 Posts
Originally Posted by Wilfred Laurier
I promise they have hangers for 7 year old Madones. All catalogued by frame make model and year. And, while I wouldn't be money on it, I would thing Trek does indeed still provide hangers for that bike.

Either way, 'Straightening' a hanger on a carbon bike is an unnecessary risk that the shop could have avoided by saying 'we dont' have a hanger, but we can get one."

I've been in this situation, where you try to do something out of the ordinary or cut corners because you don't want to have to tell a customer that their bike won't be ready today, or will be more expensive. You can generally get away with a kludge on a cheap bike, where a broken-hanger-caused scratch isn't the end of a frame.

I'm not saying it's entirely the shop's fault - maybe they told that OP's friend that he would have to wait, or that a new hanger was $50, and he complained. But hangers are definitely available, and the shop should know that, and that would have been the correct solution and would have avoided the problem.
You are so correct...you can get a hanger for just about any modern bike. May not be in shop but they can get them. I purchased one of each extra for my bikes so I would not have to wait for one if needed.
sdmc530 is offline  
Old 07-16-19, 08:52 AM
  #28  
zjrog
Senior Member
 
Join Date: Jul 2009
Posts: 1,753

Bikes: 1986 KHS Fiero, 1989 Trek 950, 1990 Trek 7000, 1991 Gary Fisher Hoo Koo E Koo, 1992 Trek 1400, 1997 Cannondale CAD2 R300, 1998 Cannondale CAD2 R200, 2002 Marin San Rafael, 2006 Cannondale CAAD8 R1000, 2010 Performance Access XCL9R

Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 284 Post(s)
Liked 385 Times in 207 Posts
Originally Posted by Wilfred Laurier
And a couple others, Wheels Manufacturing comes to mind. I ordered replacement RD hangers for my 1008 C'Dale R200, 2006 CAAD8 and 2010 Performance Access XCL9r. Just to have on hand. So, older than 7 years are generally avaialble, just not always from the OEM...

Once bent, I do not trust aluminum. Much less bent back. One of my biggest "hates" on aluminum. Being a bigger guy, I avoided aluminum bikes. But, my R200 having survived my crash 8 years ago better than I did, I am settling into being "OK" with it. Carbon fiber, on the other hand, I am unsure of. And that is more from the standpoint of in a crash, I do not want fiber in my body. I guess a hold over from my Navy time around fiber and composites after aircraft crashes... So the CAAD8 with a crabon fork, and seatpost is a HUGE stretch for me...
zjrog is offline  
Old 07-16-19, 09:24 AM
  #29  
Bike Gremlin
Mostly harmless ™
 
Bike Gremlin's Avatar
 
Join Date: Nov 2010
Location: Novi Sad
Posts: 4,422

Bikes: Heavy, with friction shifters

Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 1105 Post(s)
Liked 213 Times in 127 Posts
Originally Posted by Lucillle
There are owners of lbs and so on, on here who naturally want to disclaim liability and do so loudly and vigorously, so read all replies and think them through.
To paraphrase this a bit:
"There are owners of bicycles on here who naturally want to stick LBS with liability and do so loudly and vigorously, so read all replies and think them through."

How does that sound?
@DOS: Do think it all through and use your own best judgement.

I own a small LBS and when there's any chance of me having made a mistake, I consciously err at my expense - because I don't want to have the slightest doubt that I might have screwed someone over.

Which is what OP's LBS might have done in this case. Or it could have been their fault, of course. Either way, frame replacement is a very fair offer IMO.

We are discussing a bicycle neither of us has seen, or worked on. I don't think I'm being subjective, or have an agenda when saying that yes, it is possible for that to happen without having been the LBS's fault.

As for the hanger replacement:
Replacing the hanger would have been the safest bet, but those who have worked with customers in peak season know how things can work out and that not all the people are reasonable (not claiming that to be the case with OP's friend, but also have no idea how the whole arrangement went on).

I for one have had people insist on straightening the hanger, in spite of being informed of the risks combined with that. I've also straightened numerous hangers without any problems, including my own, high milage bicycle's hanger after a crash. For that one at least I was certain it's been straightened only once.
Bike Gremlin is offline  
Old 07-16-19, 10:20 PM
  #30  
Last ride 76 
1/2 as far in 2x the time
 
Last ride 76's Avatar
 
Join Date: Nov 2013
Location: Northern Bergen County, NJ
Posts: 1,935

Bikes: Yes, Please.

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 499 Post(s)
Liked 285 Times in 222 Posts
ironic some of the stuff in this thread. Even after the update. Sound like a decent LBS, that did something not exactly uncommon, which seems to have had a bad outcome. and is willing, (probably for a variety of reasons,) to make good on the frame. Hooray... People with different immediate interests, looking at things from different points of view, manage to find solution....
Last ride 76 is offline  
Likes For Last ride 76:
Old 07-16-19, 10:51 PM
  #31  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 27,600
Mentioned: 217 Post(s)
Tagged: 0 Thread(s)
Quoted: 18302 Post(s)
Liked 4,470 Times in 3,326 Posts
Originally Posted by Marcus_Ti
Originally Posted by Wilfred Laurier
So? They don't have everything. And the further back you go, the more hit-miss it is. Same as OEMs. Their cut off line seems to generally be about 2010-2011.

For example my 2002 BMW blue Kestrel Talon I have hanging up--I'm never finding an RD hanger for it again, in all honesty, should I ever have the urge to build that frameset up again.
They do have a lot.

But, one of the other issues is that the 3rd party derailleur hangers are generally not made by Trek, Giant, Specialized, etc. It isn't necessarily a bad thing, but for a critical part that could wipe out half the bike, I'd almost prefer keeping the OEM hanger than buying a 3rd party hanger.

Also, not all brands are the same.

Many of the Chinese E-Bay hangers are cast.

I believe Wheels Manufacturing uses CNC processing to make theirs, for a more precise cut.

Still, not necessarily OEM.
CliffordK is offline  
Old 07-16-19, 11:02 PM
  #32  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 27,600
Mentioned: 217 Post(s)
Tagged: 0 Thread(s)
Quoted: 18302 Post(s)
Liked 4,470 Times in 3,326 Posts
In this case, I think the "Squeaky Wheel" will get the grease.

But, I think we're missing bits of the story.
  • "balky rear shifting"
  • bent rear derailleur hanger.
  • New replacement rear derailleur.
  • etc.
What caused the previous damage?

Front shifting problems?

Chain Suck?

My guess is that there was some underlying pathology here, and the fault wasn't the derailleur hanger repair, but rather a failure to diagnose the underlying shifting problems.

And, a cyclist who chose to power through when the chain caught, rather than stop and diagnose the problem.
CliffordK is offline  
Old 07-17-19, 08:12 AM
  #33  
Koyote
Senior Member
 
Join Date: Sep 2017
Posts: 7,741
Mentioned: 37 Post(s)
Tagged: 0 Thread(s)
Quoted: 6866 Post(s)
Liked 10,829 Times in 4,621 Posts
Originally Posted by DOS
Update, the LBS is offering a replacement frame. Unkown yet what specific frame they deem as comparable to a 7 yr old Madone. They are Specialized, C’dale and Giant dealers but not Trek.
I think your friend is getting a pretty sweet deal. If it were me, I would at least offer to pay them for switching over the components from the damaged frame. And then I would keep coming back to this shop. They really don't have to replace the frame.
Koyote is offline  
Old 07-17-19, 10:06 AM
  #34  
Wilfred Laurier
Señor Member
 
Wilfred Laurier's Avatar
 
Join Date: Feb 2013
Posts: 5,064
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 648 Post(s)
Liked 290 Times in 214 Posts
Originally Posted by CliffordK
They do have a lot.

But, one of the other issues is that the 3rd party derailleur hangers are generally not made by Trek, Giant, Specialized, etc. It isn't necessarily a bad thing, but for a critical part that could wipe out half the bike, I'd almost prefer keeping the OEM hanger than buying a 3rd party hanger.

Also, not all brands are the same.

Many of the Chinese E-Bay hangers are cast.

I believe Wheels Manufacturing uses CNC processing to make theirs, for a more precise cut.

Still, not necessarily OEM.
You seem to be missing the point of replaceable derailleur hangers - they are supposed to be the weak link in the chain so they fail before anything else does in the case of an impact. If an OEM one was readily available, sure, but if not, there should be no hesitation to go to an aftermarket hanger, especially if your other option is to use a 'repaired' hanger, like the one that caused the problem that resulted in this thread.
Wilfred Laurier is offline  
Likes For Wilfred Laurier:
Old 07-17-19, 10:32 AM
  #35  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 27,600
Mentioned: 217 Post(s)
Tagged: 0 Thread(s)
Quoted: 18302 Post(s)
Liked 4,470 Times in 3,326 Posts
Originally Posted by Wilfred Laurier
You seem to be missing the point of replaceable derailleur hangers - they are supposed to be the weak link in the chain so they fail before anything else does in the case of an impact. If an OEM one was readily available, sure, but if not, there should be no hesitation to go to an aftermarket hanger, especially if your other option is to use a 'repaired' hanger, like the one that caused the problem that resulted in this thread.
The point is that it is supposed to be the "weak link".

And, as you suggest, it should fail before taking out the whole rear end of the bike (although that leaves the derailleur hanging loose).

If you were to replace say a carbon fiber hanger with a machined aluminum hanger, it could have very different properties than the OEM hanger.

I'm surprised that even the aluminum OEM hangers aren't designed with fracture lines.

A lack of long-term OEM supply chains for parts designed to fail is a problem.
CliffordK is offline  
Likes For CliffordK:
Old 07-17-19, 10:44 AM
  #36  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 27,600
Mentioned: 217 Post(s)
Tagged: 0 Thread(s)
Quoted: 18302 Post(s)
Liked 4,470 Times in 3,326 Posts

Hills... New Derailleur... Broken derailleur + hanger + rear-end & damaged SEAT stay.


I think we're focusing too much on the re-straightened hanger.

@DOS, what is the condition of the wheel? Was the derailleur tangled up in the spokes?

I still don't think the derailleur hanger spontaneously fell apart. Rather, something else happened that tore it up.

I mentioned chain suck earlier, but thinking about it more, I bet, for some reason the bike shifted into the spokes. Was there a spoke protector?

This still could well be a bike shop problem, not for touching up the derailleur hanger, but quite possibly not getting the rear derailleur adjusted properly (unless your buddy tinkered with the adjustment or dropped the bike on the derailleur).

The chain was sized for the bike to shift into the Big/Big ring combo, right?
CliffordK is offline  
Likes For CliffordK:
Old 07-17-19, 10:48 AM
  #37  
DOS
Senior Member
Thread Starter
 
DOS's Avatar
 
Join Date: Feb 2008
Location: Arlington, VA USA
Posts: 2,108
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 253 Post(s)
Liked 69 Times in 56 Posts
Originally Posted by Koyote
I think your friend is getting a pretty sweet deal. If it were me, I would at least offer to pay them for switching over the components from the damaged frame. And then I would keep coming back to this shop. They really don't have to replace the frame.
I suppose the sweetness of the deal depends on the frame that he is offered. I imagine some combination of LBS assessment of what level frame is a comparable replacement and what is available will come into play. That said, I am kind of surprised the shop has gone as far as frame replacement. I can only guess that they determined that the damage to the hanger was if fact the shop's fault (or at least absent evidence to the contrary, assuming so) or they decided that a happy customer and good word of mouth in a crowded market place outweighs the cost of a new frame. Generally, I like the shop in question, but it is right down the street from another very good shop and up the street from a "Trek Dealership" (the latter used to be an LBS that has been converted to a Trek-owned retail outlet) so lots of local competition.
DOS is offline  
Old 07-17-19, 11:07 AM
  #38  
Wilfred Laurier
Señor Member
 
Wilfred Laurier's Avatar
 
Join Date: Feb 2013
Posts: 5,064
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 648 Post(s)
Liked 290 Times in 214 Posts
Originally Posted by CliffordK
The point is that it is supposed to be the "weak link".

And, as you suggest, it should fail before taking out the whole rear end of the bike (although that leaves the derailleur hanging loose).

If you were to replace say a carbon fiber hanger with a machined aluminum hanger, it could have very different properties than the OEM hanger.

I'm surprised that even the aluminum OEM hangers aren't designed with fracture lines.

A lack of long-term OEM supply chains for parts designed to fail is a problem.
The general geometry of a replaceable hanger seems to be designed to bend or break, even without notched or other features obviously intended to create a break. Most of them have one part about half the thickness of the average aluminum dropout, then a sudden increase up to the entire thickness of a droupout. This should (and does, as my experience has shown) create a weak point right next to where the thickness increases.

Generally speaking, they need to be strong enough, but not too strong... a blow to the derailleur should bend the hanger but not damage the frame, and not allow the derailleur to too easily snap off. If it is too weak, as I suspect the OP's friend's repaired hanger was, it can break or begin to fail under normal shifting loads. Either the derailleur falls off and the drivetrain self destructs or damages the frame, or the hanger is bent enough to cause the derailleur to throw the chain off the cassette, which, if it happens on the inside/larger cogs, will then catch your derailleur in the spokes and possibly destroy the derailleur, wheel, frame, cassette, cogs, etc.
Wilfred Laurier is offline  
Old 07-17-19, 11:13 AM
  #39  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 27,600
Mentioned: 217 Post(s)
Tagged: 0 Thread(s)
Quoted: 18302 Post(s)
Liked 4,470 Times in 3,326 Posts
Originally Posted by Wilfred Laurier
The general geometry of a replaceable hanger seems to be designed to bend or break, even without notched or other features obviously intended to create a break. Most of them have one part about half the thickness of the average aluminum dropout, then a sudden increase up to the entire thickness of a droupout. This should (and does, as my experience has shown) create a weak point right next to where the thickness increases.

Generally speaking, they need to be strong enough, but not too strong... a blow to the derailleur should bend the hanger but not damage the frame, and not allow the derailleur to too easily snap off. If it is too weak, as I suspect the OP's friend's repaired hanger was, it can break or begin to fail under normal shifting loads. Either the derailleur falls off and the drivetrain self destructs or damages the frame, or the hanger is bent enough to cause the derailleur to throw the chain off the cassette, which, if it happens on the inside/larger cogs, will then catch your derailleur in the spokes and possibly destroy the derailleur, wheel, frame, cassette, cogs, etc.
I don't get to see the "average" broken hanger.

It is not uncommon to see photos posted on BikeForums where a broken derailleur hanger has also broken parts of the dropouts, especially with 100% carbon fiber dropouts.

Your point of making the hanger flexible enough to bend easily under normal load (not necessarily fracture) is a valid point.
CliffordK is offline  
Likes For CliffordK:
Old 07-17-19, 11:24 AM
  #40  
DOS
Senior Member
Thread Starter
 
DOS's Avatar
 
Join Date: Feb 2008
Location: Arlington, VA USA
Posts: 2,108
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 253 Post(s)
Liked 69 Times in 56 Posts
Originally Posted by CliffordK

Hills... New Derailleur... Broken derailleur + hanger + rear-end & damaged SEAT stay.


I think we're focusing too much on the re-straightened hanger.

@DOS, what is the condition of the wheel? Was the derailleur tangled up in the spokes?

I still don't think the derailleur hanger spontaneously fell apart. Rather, something else happened that tore it up.

I mentioned chain suck earlier, but thinking about it more, I bet, for some reason the bike shifted into the spokes. Was there a spoke protector?

This still could well be a bike shop problem, not for touching up the derailleur hanger, but quite possibly not getting the rear derailleur adjusted properly (unless your buddy tinkered with the adjustment or dropped the bike on the derailleur).

The chain was sized for the bike to shift into the Big/Big ring combo, right?
No wheel damage. It doesn't appear that the derailleur came in contact with the wheel at all.
DOS is offline  
Old 07-20-19, 12:18 AM
  #41  
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Posts: 28,353

Bikes: 1987 Bianchi Campione

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 25 Times in 18 Posts
If this was our shop.

We would repair all. Regardless of who was at fault, there was a repair and a failure afterwards. We always do a 30 day repair warranty on EVERYTHING. Now this isn't a black and white line.

If it was OBVIOUS it was YOUR fault, we would not fix it and let you know why.

If it was a grey area like this, typically we'd err on the side of we ****ed up and maintain the relationship with the customer.
operator is offline  
Old 07-20-19, 12:20 AM
  #42  
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Posts: 28,353

Bikes: 1987 Bianchi Campione

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 25 Times in 18 Posts
Originally Posted by Wilfred Laurier
The general geometry of a replaceable hanger seems to be designed to bend or break, even without notched or other features obviously intended to create a break. Most of them have one part about half the thickness of the average aluminum dropout, then a sudden increase up to the entire thickness of a droupout. This should (and does, as my experience has shown) create a weak point right next to where the thickness increases.

Generally speaking, they need to be strong enough, but not too strong... a blow to the derailleur should bend the hanger but not damage the frame, and not allow the derailleur to too easily snap off. If it is too weak, as I suspect the OP's friend's repaired hanger was, it can break or begin to fail under normal shifting loads. Either the derailleur falls off and the drivetrain self destructs or damages the frame, or the hanger is bent enough to cause the derailleur to throw the chain off the cassette, which, if it happens on the inside/larger cogs, will then catch your derailleur in the spokes and possibly destroy the derailleur, wheel, frame, cassette, cogs, etc.
Highly unlikey it'll damage cogs.

Usually at most RD, hanger obviously and chain.
operator is offline  
Old 07-20-19, 06:11 AM
  #43  
DOS
Senior Member
Thread Starter
 
DOS's Avatar
 
Join Date: Feb 2008
Location: Arlington, VA USA
Posts: 2,108
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 253 Post(s)
Liked 69 Times in 56 Posts
Originally Posted by operator
If this was our shop.

We would repair all. Regardless of who was at fault, there was a repair and a failure afterwards. We always do a 30 day repair warranty on EVERYTHING. Now this isn't a black and white line.

If it was OBVIOUS it was YOUR fault, we would not fix it and let you know why.

If it was a grey area like this, typically we'd err on the side of we ****ed up and maintain the relationship with the customer.
Seems a reasonable philosophy. I don’t evny the shop guys in this type of situation. There are a lot of mistreated bikes out there. I have been standing in shops more than once, waiting my turn with the mechanics, while some customer with some absurdly mistreated bike argued that the mechanic should be able to do this or that to get the bike working at 1/2 the price or in 1/4 of the time the shop had quoted.
DOS is offline  
Old 07-20-19, 10:10 PM
  #44  
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Posts: 28,353

Bikes: 1987 Bianchi Campione

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 25 Times in 18 Posts
Originally Posted by DOS
Seems a reasonable philosophy. I don’t evny the shop guys in this type of situation. There are a lot of mistreated bikes out there. I have been standing in shops more than once, waiting my turn with the mechanics, while some customer with some absurdly mistreated bike argued that the mechanic should be able to do this or that to get the bike working at 1/2 the price or in 1/4 of the time the shop had quoted.
I've made my fair share of mistakes on customer bikes, a good shop always has your back, even when you ****ed up.

It doesn't cost that much money in the long run to fix whatever is broken and to keep a customer. Unless you were a customer they didn't want, lol.
operator is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
cyclist2000
Bicycle Mechanics
8
12-01-13 03:46 PM
bean4158
Road Cycling
24
06-26-12 10:38 AM
tigerdog
Bicycle Mechanics
25
11-29-11 02:59 PM
TromboneAl
Bicycle Mechanics
8
06-25-11 06:12 PM
stristra
Road Cycling
6
04-25-10 11:24 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.