Catastrofic brake cable failure
#1
Catastrofic brake cable failure
So I wasn't really sure where to post this since I was commuting from work riding my single speed when this happened..... so it spans a few different forums.
Was riding along at maybe 18mph on a busy downtown street when a car coming the opposite way tried to make a right hand turn (UK roads) across traffic into a side street. I pulled hard on both brakes and hear a "pop-ping" and my rear brake goes dead. Pulled on the front brake... "pop-ping", now no brakes at all. Lucky the car saw me at the last minute and I was able to swerve around it. Pulled a Fred Flintstone stop at the next traffice light and looked over the brakes. At first I figured I had stripped out both of the crimp connections at the brake calliper, but both of them were fine. Looked at the brake levers and found that both of the brake wires had catastrofically failed inside the levers.
Got home and took a closer look. The stopper at the end of the brake line didn't strip, but each wire had actually completely failed. Only thing I can figure is that I hadn't adjusted the brakes in a long time, so to get full stopping power you had to pull them down pretty far. This may have cause the wire to rub against an edge inside the lever and eventually fatigue the wires.
Still kinda crazy that both wires should fail at the same time. Maybe someone at my work had it out for me and cut the brake lines
Guess I will be checking my brake wires on a more regular basis in the future....


Was riding along at maybe 18mph on a busy downtown street when a car coming the opposite way tried to make a right hand turn (UK roads) across traffic into a side street. I pulled hard on both brakes and hear a "pop-ping" and my rear brake goes dead. Pulled on the front brake... "pop-ping", now no brakes at all. Lucky the car saw me at the last minute and I was able to swerve around it. Pulled a Fred Flintstone stop at the next traffice light and looked over the brakes. At first I figured I had stripped out both of the crimp connections at the brake calliper, but both of them were fine. Looked at the brake levers and found that both of the brake wires had catastrofically failed inside the levers.
Got home and took a closer look. The stopper at the end of the brake line didn't strip, but each wire had actually completely failed. Only thing I can figure is that I hadn't adjusted the brakes in a long time, so to get full stopping power you had to pull them down pretty far. This may have cause the wire to rub against an edge inside the lever and eventually fatigue the wires.
Still kinda crazy that both wires should fail at the same time. Maybe someone at my work had it out for me and cut the brake lines

Guess I will be checking my brake wires on a more regular basis in the future....


#2
Senior Member
Joined: Aug 2005
Posts: 33,657
Likes: 1,119
From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Brake cable failure is relatively rare if they are replaced with any reasonable frequency and having BOTH fail has got to be VERY unusual. I'm happy you came through it ok.
What make were the cables? Shimano and Campy cables are particularly good and worth the extra cost.
What make were the cables? Shimano and Campy cables are particularly good and worth the extra cost.
#3
Not sure about the make of cables, they came stock on my IRO Jamie Roy. The bike is only about two years old, but I use the bike every day for city commuting so am on the brakes a lot.
#4
Senior Member
Joined: Nov 2006
Posts: 53
Likes: 0
From: mostly flat florida though I do live near the ridge I have 200' foot elevation ride wich is rare!!
Bikes: El cheapo specials for road and Mtb and a GT bmx
This a good example of not inspecting and adjusting your equipment. Sure it is only a bike but you are sharing
the roads with cars and little things like this can cause you a crash. You could have used the old school foot
on the back tire trick to stop. The best time is after you rest after a ride and using the sun or a bright light
(I like those led hat lights) clean the frame with a rag and inspect your welds, wear points, chain for kinks
or loose plates, and grab your brake levers and really squeeze the piss out of them like you were in a panic
stop situation and that will hopefully point out any frayed spot or even a too loose cable pinch bolt which will
cause a no brake situation.
the roads with cars and little things like this can cause you a crash. You could have used the old school foot
on the back tire trick to stop. The best time is after you rest after a ride and using the sun or a bright light
(I like those led hat lights) clean the frame with a rag and inspect your welds, wear points, chain for kinks
or loose plates, and grab your brake levers and really squeeze the piss out of them like you were in a panic
stop situation and that will hopefully point out any frayed spot or even a too loose cable pinch bolt which will
cause a no brake situation.
#5
Senior Member
Joined: Apr 2006
Posts: 2,343
Likes: 0
From: Gainesville/Tampa, FL
Bikes: Trek 1000, two mtbs and working on a fixie for commuting.
If I remember correctly, Shimano brake cables a few years back had a recall for the exact same problem. I could be wrong though.
Here, found it:
https://www.nashbar.com/recall.cfm
Here, found it:
https://www.nashbar.com/recall.cfm
#6
?I've been riding and working on my bike for 20+ years. I never work on both brakes at the same time. I'll do one, get a couple of rides in then do the other - trying to minimize the chance of both failing due to workmanship issues.
#7
Senior Member
Joined: Mar 2008
Posts: 5,559
Likes: 53
From: The 'Wack, BC, Canada
Bikes: Norco (2), Miyata, Canondale, Soma, Redline
Did they fail right at the edges of the swaged on end?
This is why MTB brakes use the barrel end in a sort of fork recess. When greased or equipped with a plastic slip cover the barrel end can turn in the lever's recess and help avoid a lot of the flexing that would otherwise occur right where it passes from the swaged on end.
But these style of bar end brakes don't do it that way. Instead they use the road bike ball end which sits solidly in the opening. And it doesn't take much to realize that without the ability to pivot that the cable is going to flex right at that end on a regular basis. Obviously this works for a while but it would be worth doing new cables on a regular basis. Like once a year.
Any idea how long you had used the same cables?
This is why MTB brakes use the barrel end in a sort of fork recess. When greased or equipped with a plastic slip cover the barrel end can turn in the lever's recess and help avoid a lot of the flexing that would otherwise occur right where it passes from the swaged on end.
But these style of bar end brakes don't do it that way. Instead they use the road bike ball end which sits solidly in the opening. And it doesn't take much to realize that without the ability to pivot that the cable is going to flex right at that end on a regular basis. Obviously this works for a while but it would be worth doing new cables on a regular basis. Like once a year.
Any idea how long you had used the same cables?
#8
Senior Member
Joined: Aug 2005
Posts: 33,657
Likes: 1,119
From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
If I remember correctly, Shimano brake cables a few years back had a recall for the exact same problem. I could be wrong though.
Here, found it:
https://www.nashbar.com/recall.cfm
Here, found it:
https://www.nashbar.com/recall.cfm
#9
Senior Member
Joined: Mar 2008
Posts: 5,559
Likes: 53
From: The 'Wack, BC, Canada
Bikes: Norco (2), Miyata, Canondale, Soma, Redline
I'm not so sure this isn't a cable end issue as well. Remember that when the levers are fully back the end of the swaged part is pretty darn close to where the end is showing in the housing. And without the end to hold the cable the broken end will tend to spring back like this one is.
Did you manage to keep one or both of the ends? That'll tell you where the wear is located for sure.
I'm also basing this on the fact that so many of the strands are all the same length in the picture. If the failure was due to a progressive wearing of the cable dragging over the metal of the lever you'd see a major wear groove around the opening where the strands are peeking out in the first picture. Also the varioius strands would have brokent at different places and would show signs of wear in the third picture. Instead all I see is a lot of similar length cleanly broken strands that obviously all flexed and fatigued at the same point.
So I still say it's a flex at the swaged ball end deal..... And in the words of the immortal Doug McKenzie "That's my story and I'm sticking to it, eh..."
Did you manage to keep one or both of the ends? That'll tell you where the wear is located for sure.
I'm also basing this on the fact that so many of the strands are all the same length in the picture. If the failure was due to a progressive wearing of the cable dragging over the metal of the lever you'd see a major wear groove around the opening where the strands are peeking out in the first picture. Also the varioius strands would have brokent at different places and would show signs of wear in the third picture. Instead all I see is a lot of similar length cleanly broken strands that obviously all flexed and fatigued at the same point.
So I still say it's a flex at the swaged ball end deal..... And in the words of the immortal Doug McKenzie "That's my story and I'm sticking to it, eh..."
#10
Senior Member
Joined: May 2008
Posts: 679
Likes: 1
From: Calgary, Alberta
Over time the single strands of wire gradually break one at a time right next to the lug that the brake levers hold. This gradually makes them weaker and sooner or later that lug will pop right off, even without an unusually hard stop. I don't think most of my brake cables last 2 years without that happening. Since you were in a situation where you gave each an unusually hard pull, I think it is reasonable that it could be just normal wear and tear plus that unusual situation. I think that has a 99% better chance of explaining the situation than sabotage. There's probably no need to go out and buy a gun.
#11
Really Old Senior Member


Joined: Feb 2007
Posts: 14,687
Likes: 1,928
From: Mid Willamette Valley, Orygun
Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds. 2019 Giant Explore E+3
That's why, about once a month, I do a full panic stop on my side street. IF it's going to fail, I want it to fail then, not when a car is in the immediate vicinity.
#12
Year-round cyclist

Joined: Apr 2002
Posts: 3,023
Likes: 3
From: Montréal (Québec)
I look at the photos of the cable break and really wonder if those cables have been cut deliberately. Only one strand isn't broken at the same level as the other ones, yet a normal failure would show much more ragged strands.
Looks intriguing to say the least.
Looks intriguing to say the least.
#13
...But these style of bar end brakes don't do it that way. Instead they use the road bike ball end which sits solidly in the opening. And it doesn't take much to realize that without the ability to pivot that the cable is going to flex right at that end on a regular basis......
Any idea how long you had used the same cables?
Any idea how long you had used the same cables?
#14
I wish my life was exciting enough that some one would actually want to kill me......
#15
Yes, me too. The recall was specifically for North America. They look cut to me. Who hates you that much?
#16
Senior Member
Joined: Aug 2007
Posts: 409
Likes: 1
From: Montréal, QC (Canada)
Bikes: 2008 Surly LHT complete & 1988-ish fuglyfixed Specialized RockHopper
#17
<snip>
I'm also basing this on the fact that so many of the strands are all the same length in the picture. If the failure was due to a progressive wearing of the cable dragging over the metal of the lever you'd see a major wear groove around the opening where the strands are peeking out in the first picture. Also the various strands would have broken at different places and would show signs of wear in the third picture. Instead all I see is a lot of similar length cleanly broken strands that obviously all flexed and fatigued at the same point.
I'm also basing this on the fact that so many of the strands are all the same length in the picture. If the failure was due to a progressive wearing of the cable dragging over the metal of the lever you'd see a major wear groove around the opening where the strands are peeking out in the first picture. Also the various strands would have broken at different places and would show signs of wear in the third picture. Instead all I see is a lot of similar length cleanly broken strands that obviously all flexed and fatigued at the same point.
It looks like all the cable strands broke at the bottom of the cable end. Cables are meant to be flexed that way- if you look inside a conventional road brake lever, you'll see that the end is held by a pivoting dingus that keeps the cable from flexing.
IMO, those brake levers are improperly designed. I'd get rid of them.
__________________
Jeff Wills
Comcast nuked my web page. It will return soon..
Jeff Wills
Comcast nuked my web page. It will return soon..
#18
Senior Member


Joined: Jul 2005
Posts: 11,754
Likes: 26
From: Mesa, AZ
Bikes: Moots RCS, tandem, beach-cruiser, MTB, Specialized-Allez road-bike, custom track-bike
Those levers need to have a roller for the cable so it doesn't take a sharp bend where it exits. As the lever gets squeezed more and more, the cable gets bent more and more at the hole. Brake-cables don't take kindly to being bent 90-degrees.
#19
Senior Member
Joined: Mar 2008
Posts: 5,559
Likes: 53
From: The 'Wack, BC, Canada
Bikes: Norco (2), Miyata, Canondale, Soma, Redline
+1
It looks like all the cable strands broke at the bottom of the cable end. Cables are meant to be flexed that way- if you look inside a conventional road brake lever, you'll see that the end is held by a pivoting dingus that keeps the cable from flexing.
IMO, those brake levers are improperly designed. I'd get rid of them.
It looks like all the cable strands broke at the bottom of the cable end. Cables are meant to be flexed that way- if you look inside a conventional road brake lever, you'll see that the end is held by a pivoting dingus that keeps the cable from flexing.
IMO, those brake levers are improperly designed. I'd get rid of them.
It looks to me like these are cyclocross top bar levers that have been adapted to use on the ends of the bullhorns. I know I've seen this suggested here and elsewhere before but now I'm not sure it's all that good an idea given what has happened here. As mentioned it's not a good way to support the cable and ball end.
Gotta go check the Cane Creek bullhorn levers that I just got recently......
#20
Actually, they are reverse brake levers, designed for this application. I don't think the angle can get that extreme either. I still think the cables were cut.
https://www.jensonusa.com/store/produ...ke+Levers.aspx
https://www.jensonusa.com/store/produ...ke+Levers.aspx
#22
Mad bike riding scientist




Joined: Nov 2004
Posts: 29,212
Likes: 6,287
From: Denver, CO
Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones
I'd suspect the brake lever. The movement of that lever is very different from the type of lever you find on just about any other brake. I'd suspect that you can develop more leverage on the cable with it than with a road or mountain bike lever.
__________________
Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
#23
Senior Member


Joined: May 2010
Posts: 5,634
Likes: 2,504
From: Bastrop Texas
Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites
Thanks for leaving this post up - I just switched over to bar end brakes on bullhorn handle bars and will keep a close eye out for this kind of problem - Has there been a recurrence over the past two years???
#24
Senior Member
Joined: Oct 2010
Posts: 197
Likes: 0
From: Toronto
Bikes: 1986 Miele Elite S, SunTour Sprint
based on the pics i would say these levers are the real problem, i just put together a bike with this lever set up and they had pviots for the cables in order to prevent the bend that caused this break. As for the one strand that's longer, i wouldn't be surprised if that strand is split somwhere else aswell and just slid up higher than the rest for the photo.
#25
Senior Member
Joined: Jun 2007
Posts: 12,257
Likes: 5
From: A Coffin Called Earth. or Toronto, ON
Bikes: Bianchi, Miyata, Dahon, Rossin
judging by the fact that we haven't heard of anything similar, I'd say you're perfectly safe in the "all those not here, raise your hands" sort of way.
__________________
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm




