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almost died .... (Easton, we have a problem)

saruti

Turbo Monkey
Oct 29, 2006
1,167
73
Israel
a week a go, I was riding my bike (alone...)
got to one of my favorite trails and started going down.
on a big jump, I landed, and found my self on the ground. smashing my left shoulder hard.
all my body hurt, and I didn't understand what happen...
I was on the ground, looking on my bike, and wow.....
IMG_20141218_140938.jpg


my carbon bar brook !!
I took off my j\helmet and searched for impact. but surprisingly, it was all good.
my shoulder got all the impact from the ground, and my right hand got all the weight of the body so it hurt like HELL.
after sitting on the ground for 10 minutes, I started walking back to my car.
got to the hospital, some x-rays , and found out I dislocated my left shoulder, and brook a finger on my right hand.
I think I went really cheap out of this crash.
IMG-20141218-WA0006.jpg

the bar brook exactly at the brake lever contact point.
and I'm not a rider who attach his levers strong to the bar.
a week now, It got me thinking about the tests that company's are doing to carbon bars....
all the tests are without any grips or\and brake levers.
I made a picture of what I think happen during the use of carbon bar with brake levers\grips on it
carbon tests.png


as you can see, during the load from the rider on the bar, it gest up and down. and the brake lever\grip, make little cuts on it.
what leads to a failure of the bar.
I think company's should start making their tests better.
as for me, I cant trust a carbon bar any more.... :(
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,915
1,200
That's not cool... which model / width bar was it?
Heal up soon!
 
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Steve M

Turbo Monkey
Mar 3, 2007
1,991
45
Whistler
Have seen this happen on my housemate's Havoc 31.8 carbons too. Same place, at the brake lever clamp (on both sides), which he runs loose enough that you can push the lever around the bar with a little bit of force (to avoid broken levers in crashes). Fortunately however, he found the crack before it let go catastrophically like that. From memory, the only reason he found it was because the same thing had happened to someone else, so he went and checked!
 

mykel

closer to Periwinkle
Apr 19, 2013
5,071
3,780
sw ontario canada
I have a Havoc that is 3(?) years old now.
I run my levers so they will move...
Guess I have a detailed inspection to make.
Cheers for the heads up.
Hope you heal up quick.
Merry Christmas
 

Dirk77

Monkey
Feb 15, 2014
233
48
Damn, that's really a bitch.. Shit happens i guess, but I'd be pissed..

I just can't get myself to buy carbon bars or carbon rims. Rims are too expensive anyways..

I do ride a carbon dh frame,, from kona.. So i guess i am a little crazy though!
 

Kanye West

220# bag of hacktastic
Aug 31, 2006
3,740
470
Clamps on flexures like that should always be radiused at the edges of their clamping areas for this exact reason. They're also extremely torque sensitive, and equal gap (for a 2pc clamp) so as to not distort the profile is critical.

Basically, lots of shit to go wrong. Hope those couple hairs of weight savings are worth it for people. Looks like you did get lucky.
 

Kanye West

220# bag of hacktastic
Aug 31, 2006
3,740
470
Just out of curiosity, what part of the bar is left inside the brake clamp? Is it only partially clamped or is there excess material sticking out? The break looked angled, migrating inwards from the rear of the bar.
 

jstuhlman

bagpipe wanker
Dec 3, 2009
16,628
12,922
Cackalacka du Nord
*goes out and looks at sixc bars

good advice to check clamps for rounded edges. wonder would a layer if electrical tape under the clamp might give a bit of additional protection?
 

dump

Turbo Monkey
Oct 12, 2001
8,196
4,419
Carbon bars are (still) a retarded idea.
2001 is calling... carbon bars... how soon we forget... still don't do it :)

Of all the places to take the risk of catastrophic failure, the handlebar is not the place.

Glad you're ok. My buddy switches out his (aluminum) handlebars every season for exactly this reason .
 

StiHacka

Compensating for something
Jan 4, 2013
21,560
12,504
In hell. Welcome!
Ugh. Time for Kore Torsion!


I like my RF Atlas. I looked at the SixC bars as well but could not justify the price difference. I think I am staying with Al for a while.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,915
1,200
Has anyone actually broken or seen a broken SIXC bar?

I don't run one but all these breakages seem to be Easton, and from my quick googlez there are plenty of SIXC bars out there. They would suffer from the same effects of levers twisting and potentially creating stress risers on the outer layer (or cutting right through it), so I wonder if Raceface uses a stronger coating?

wonder would a layer if electrical tape under the clamp might give a bit of additional protection?
Not a bad idea I reckon, the rubber would reduce the torque needed for a given level of friction and would provide protection against surface damage when they rotate in a crash.
 
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jstuhlman

bagpipe wanker
Dec 3, 2009
16,628
12,922
Cackalacka du Nord
i've had a few friends with upper level delam/wear in the sixc around various clamp points, but no catastrophic fails.

i'm just scared of what's gonna happen if my crabon stem spacers give out...
 

Kanye West

220# bag of hacktastic
Aug 31, 2006
3,740
470
rounded edges? 2-piece clamps? which brake or shifters have either of those?
I think Avid Juicy's actually? I recall those being 2pc clamps and I think they were cast and not machined after on the ID. The 2pc clamp thing isn't much of a benefit in this case because it's one more thing that can mess with the bar. Single bolt keeps (more) consistent clamping around the whole bar.
 
Aug 4, 2008
328
4
I have seen shit like this too many times to trust carbon for anything important on front of the bike.

Don't get me wrong, I love carbon, I love how it feels. But I would never use it for bar, stem or fork for that matter.

I can deal with shit breaking on the backside of the bike, but I don't want to deal with shit breaking in the front.
 

Electric_City

Torture wrench
Apr 14, 2007
1,993
716
Two years ago @ the Reading race I went over the guard rail and right down the fall line. The dirt was dry and like sand. I couldn't turn when I needed to and went head on into a tree. The brake lever twisted as intended. I straightened it out and finished the run. Knowing I had to re-do that run so I got the bugs out of my head, I went back up and did it. 2 more practice runs and the timed run on race day and the bar never failed. I took the brakes off for some reason that week and saw the paint gone and a gouge the thickness of a business card into the aluminum. I obviously replaced it right then. It was a FUNN fatboy, 31.8 and aluminum. I never understood the idea of lightweight over strength in a sport, like mountain biking in general - nevermind DH- where failure will lead to such catastrophic injury.

I know, it's technology and we need to move forward. But at what cost is weight more important than strength?
 

jackalope

Mental acuity - 1%
Jan 9, 2004
7,596
5,894
in a single wide, cooking meth...
Ran SixCs for a good while with no issues, and now have a Bromag BZA which so far has, well, not catastrophically failed. But stuff like this certainly makes you think twice^10. And while no one wants a bar to fail, I think that would be (slightly) more preferable than a carbon seat post, as there was a monkey that damn near bled to death because of a failed carbon post.

#Iguessthesyndicatewillbeswitchingbacktoalum
 

w00dy

In heaven there is no beer
Jun 18, 2004
3,417
51
that's why we drink it here
2001 is calling... carbon bars... how soon we forget... still don't do it :)

Of all the places to take the risk of catastrophic failure, the handlebar is not the place.

Glad you're ok. My buddy switches out his (aluminum) handlebars every season for exactly this reason .
This is a good PSA for the younger crowd.
Carbon bars are seeing a resurgence and being advertised for aggressive use. Carbon layups and design have improved greatly in the past decade, but the material is the same. It fails catastrophically after fatigue.

Cut the older bars down and put them on your fixie. They're not safe after a solid season of aggressive use. A good crash should warrant an inspection.
 

marshalolson

Turbo Monkey
May 25, 2006
1,770
519
Since the bar broke exactly right at the clamp, and just to bear repeating, if you don't know what torque:

1. The bar is rated for
2. The brake lever was torqued to

It's impossible to call this Easton's fault

Over torquing aluminum is much more difficult than carbon. 5nm is not all that much. Always use a torque wrench on carbon, or don't use carbon.

If you can't be bothered to buy a $25 tool to properly install $175 bars,then don't use carbon. If you crash all over the place, or can't afford to buy new bars once they see a few big nicks, then don't buy carbon.
 
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4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,884
448
[QUOTE="jackalope, post: 4025562, member: 5627] ...a monkey that damn near bled to death because of a failed carbon post.

#Iguessthesyndicatewillbeswitchingbacktoalum[/QUOTE]

I'm blanking on the member name, but are you thinking of the time where the carbon steerer on a revelation fork snapped and stabbed him inside of his thigh? It was the incident where Bighittr left him for dead.
(Searched quite a bit for the thread, methinks it's gone)

On another note, I'd be interested to know how often the syndicate guys swap out their bars.
 

jackalope

Mental acuity - 1%
Jan 9, 2004
7,596
5,894
in a single wide, cooking meth...
^^
That may be it, memory is fuzzy these days. Although I swore it was a seat post which sheared off and stabbed him in the leg. Regardless, teh suck for sure.

As for the Syndicate and I'd guess most factory supported teams, I'd wager they swap out components pretty regularly, but that's based on little or no facts. :thumb:

At the very least, I'd assume everything is properly torqued by a legit mechanic, as marshal was suggesting.
 

dump

Turbo Monkey
Oct 12, 2001
8,196
4,419
On another note, I'd be interested to know how often the syndicate guys swap out their bars.
How often Synicate swaps out their carbon bits is pretty much irrelevant to me and you. Different usage and their parts only have to last one run since mechanics with full stock are waiting at the bottom. I would guess a couple of bars a season.
 

wiscodh

Monkey
Jun 21, 2007
833
121
303
It fails catastrophically after fatigue.n.
Um no it doesn't
Carbon fiber has a "infinite" fatigue life for un damaged properly manufactured material

That's not a fatigue failure. Its a crack propagation based on previous damage
 

Jm_

sled dog's bollocks
Jan 14, 2002
18,855
9,560
AK
Because the handlebar is a pretty critical interface and I intended to do quite a few DH days at the ski resort on my "all mountain" type bike, I went with the Answer Pro Taper DH Carbon 780 bar. It's seriously thick and compared to my crack brothers bar of the same width, it makes the CB look like it's made out of paper. Sure, it's not light, somewhere around 250g, but it's crazy strong and if I'm going to be flying through the air and occasionally casing a jump or two, I need the "strength" for the next-level of riding (DH), rather than going with the XC/AM type bar and occasionally push it OUT of it's intended usage.

This isn't the place to save weight IMO, but you can end up with a far higher strength to weight ratio going with a carbon bar, you can also end up with a way lighter bar if you're willing to "risk it", but on this bike, I am not.

A crack is basically a local-overstress event, although a pre-existing flaw causing a crack would be an under-stress event.
 

jackalope

Mental acuity - 1%
Jan 9, 2004
7,596
5,894
in a single wide, cooking meth...
Would be interesting to rank various carbon parts on the "fuck no to hell yes" spectrum.

Bars, stems, seat posts, cranks, fork lowers, fork steerers, tallboy cages, pedal bodies, dildos, derailleur cages, frames (complete and halvsies), saddle rails, rims, etc...
 

HAB

Chelsea from Seattle
Apr 28, 2007
11,580
2,006
Seattle
Would be interesting to rank various carbon parts on the "fuck no to hell yes" spectrum.

Bars, stems, seat posts, cranks, fork lowers, fork steerers, tallboy cages, pedal bodies, dildos, derailleur cages, frames (complete and halvsies), saddle rails, rims, etc...
Rims
Dildos
Frames
Cranks
Cages (derailleur)
Cages (bottle)
Bars
Fork steerers
Seatposts
Stems
Getting hit by a car
Seat rails