Cutter Carbon Bars..... failed
11-13-11 | 11:26 PM
#52
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From: RTP, NC
Bikes: LOOK 595 & Cannondale CAAD9
i think the reason many of us doubt the ability of the helping friend is because he continued to keep wrenching after hearing cracking sounds.
would stopping after cracking fix any issue with the bars? no.
would continuing to wrench after hearing cracking in carbon bars fix anything? no.
it is irrational and counterproductive to continue the process once failure has occurred.
also, i found it weird that the friends mentions thinking that the cracking might have been the sound of the bolts threading in.
if the integrity of the bars was compromised, but was not visible from the surface, then the safety of the rider would be at risk.
if i worked on someone's bike and heard cracking or any other breaking noise, i would inform the person that the bike may not be suitable to ride.
so while we do not have proof that the failure was due to the mechanic or the handlebars, there are many of us who would refuse the service of the man who keeps cranking after hearing cracking.
ps- in addition, that the mechanic will not admit that it was foolish or an "dumb moment" to continue wrenching after hearing cracking, adds to the doubt of his claims.
would stopping after cracking fix any issue with the bars? no.
would continuing to wrench after hearing cracking in carbon bars fix anything? no.
it is irrational and counterproductive to continue the process once failure has occurred.
also, i found it weird that the friends mentions thinking that the cracking might have been the sound of the bolts threading in.
if the integrity of the bars was compromised, but was not visible from the surface, then the safety of the rider would be at risk.
if i worked on someone's bike and heard cracking or any other breaking noise, i would inform the person that the bike may not be suitable to ride.
so while we do not have proof that the failure was due to the mechanic or the handlebars, there are many of us who would refuse the service of the man who keeps cranking after hearing cracking.
ps- in addition, that the mechanic will not admit that it was foolish or an "dumb moment" to continue wrenching after hearing cracking, adds to the doubt of his claims.
11-13-11 | 11:30 PM
#54
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From: RTP, NC
Bikes: LOOK 595 & Cannondale CAAD9
I wish it was just the clear coat, but unfortunately it isn't. The bars are definitely screwed. It's hard to tell from the pics, but the top of the bar essentially collapsed and created a ridge that protruded upwards.
11-13-11 | 11:33 PM
#55
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From: Orange County, CA
Was it these?
https://www.realcyclist.com/cutter-carbon-road-handlebar
RealCyclist might take them back...they have excellent CS
https://www.realcyclist.com/cutter-carbon-road-handlebar
RealCyclist might take them back...they have excellent CS
11-13-11 | 11:37 PM
#59
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From: Vienna, VA
Bikes: 2010 Fuji Roubaix 2.0. 2006 Iron Horse Azure Expert
11-13-11 | 11:38 PM
#60
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From: Vienna, VA
Bikes: 2010 Fuji Roubaix 2.0. 2006 Iron Horse Azure Expert
Was it these?
https://www.realcyclist.com/cutter-carbon-road-handlebar
RealCyclist might take them back...they have excellent CS
https://www.realcyclist.com/cutter-carbon-road-handlebar
RealCyclist might take them back...they have excellent CS
11-13-11 | 11:40 PM
#61
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do you read like this
?and remember, keep on smiling
ps- this guy gives lessons on basic maintenance
11-13-11 | 11:41 PM
#62
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Was it these?
https://www.realcyclist.com/cutter-carbon-road-handlebar
RealCyclist might take them back...they have excellent CS
https://www.realcyclist.com/cutter-carbon-road-handlebar
RealCyclist might take them back...they have excellent CS
hmmm...but i already love my aluminum fsa compact bars...bike project coming soon?
11-13-11 | 11:45 PM
#63
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From: RTP, NC
Bikes: LOOK 595 & Cannondale CAAD9
) that has a fair amount of experience with SRAM products and they will tell you it's going to be a crap shoot when you leave out the door with a SRAM FD. That's just how it is, even if you have had great experiences with SRAM front shifting. But let's keep this one on topic, k?
11-14-11 | 12:13 AM
#64
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From: Mesa, AZ
Bikes: Bianchi Infinito CV 2014, TREK HIFI 2011, Argon18 E-116 2013
If you are ever on the east coast, you are welcome to give my Look 595 w/ 6700 FD a spin. I think you would be pleasantly surprised at how well tuned the entire bike is, front shifting and all. Some bike setups don't like Red FDs and some do. Check with any reputable bike shop (roadwarrior's doesn't count ) that has a fair amount of experience with SRAM products and they will tell you it's going to be a crap shoot when you leave out the door with a SRAM FD. That's just how it is, even if you have had great experiences with SRAM front shifting. But let's keep this one on topic, k?
) that has a fair amount of experience with SRAM products and they will tell you it's going to be a crap shoot when you leave out the door with a SRAM FD. That's just how it is, even if you have had great experiences with SRAM front shifting. But let's keep this one on topic, k?
11-14-11 | 12:16 AM
#65
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Just to play devil's advocate, as long as he was well below the torque spec, I think he was right to keep torqueing. At least he ended up with an answer and he's safe.
What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
11-14-11 | 12:20 AM
#66
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From: RTP, NC
Bikes: LOOK 595 & Cannondale CAAD9
Just to play devil's advocate, as long as he was well below the torque spec, I think he was right to keep torqueing. At least he ended up with an answer and he's safe.
What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
11-14-11 | 01:14 AM
#67
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Well I don't know you from adam, so I might be a lunatic and you might actually be an awful bike mechanic. But you sound like you know what you are doing and for me the bottom line is this was an ultra lightweight bar at a dirt cheap price. To me that means a thin bar/thin carbon which should at least suggest the possibilty that it might be a bit fragile or with cheap price, that quality control might be an issue. On the other hand the best manufacturer's still have to warranty out frames that crack under normal use. It may be that the Cutter bars are good quality in general but that doesn't mean you didn't get a defective one that cracked well under torque spec.
I thought about this bar but the weight/price seemed too good to be true. I think I'm gonna stick with my heavy FSA bar.
I thought about this bar but the weight/price seemed too good to be true. I think I'm gonna stick with my heavy FSA bar.
11-14-11 | 01:21 AM
#68
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From: Mesa, AZ
Bikes: Bianchi Infinito CV 2014, TREK HIFI 2011, Argon18 E-116 2013
What on earth are we thinking? shaving a few grams of the handle bar weight??? This seams insane... yes off the wheel weight... we can justify that (Not rationally of course), and perhaps on the componentry going to cnc over cast parts... or perhaps CF, but on the place closest to your face?? I would be more than happy to go with heavier handle bars that are reliable over light ones that might 'esplode' while riding.. not because they are CF but because they are as thin and light as tinfoil!... Go Heavy Bars!
11-14-11 | 02:21 AM
#69
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[...] the bottom line is this was an ultra lightweight bar at a dirt cheap price. To me that means a thin bar/thin carbon which should at least suggest the possibilty that it might be a bit fragile or with cheap price, that quality control might be an issue.
I thought about this bar but the weight/price seemed too good to be true. I think I'm gonna stick with my heavy FSA bar.
I thought about this bar but the weight/price seemed too good to be true. I think I'm gonna stick with my heavy FSA bar.
11-14-11 | 02:25 AM
#70
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What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
-visually inspect
-contact lbs or manufacturer for a better idea of what to do
also, sometimes torque wrenches need to be recalibrated.
if i was not confident in my handlebars, i would use a different pair.
11-14-11 | 09:54 AM
#71
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The torque spec on a 3mm bolt means next to nothing. Torque specs are pretty much worthless for bolts less than 1/4" due to high variance in thread friction. To illustrate, insert the bolts dry and 5Nm will might have the bars slipping. Put grease on the threads and at 5Nm you might have enough bolt tension to crush the bars. The important is bolt tension; in big bolts, tightening torque correlates well with bolt tension. In a little bolt, thread friction is a huge factor and the correlation between bolt tension and tightening torque is not good.
11-14-11 | 10:21 AM
#72
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This is another way of saying there is a learning curve, and there is no way to shortcut that. If you are new to tightening bolts over fragile joints, take it extremely slow else you end up like the OP. Also, own your mistakes and learn from them. If you can't afford to make mistakes, let a shop do the work or work with more robust parts.
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11-14-11 | 10:26 AM
#73
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Just to play devil's advocate, as long as he was well below the torque spec, I think he was right to keep torqueing. At least he ended up with an answer and he's safe.
What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
What happens if he's still far from his intended torque spec and he and his friends hear a distinct "crack?" What do you do? Ride it knowing that it might not be tight enough (unsafe) or that it might be cracked (unsafe)? Bar looks ok visually...does that mean it didn't crack? Maybe not. It's not as though he kept torquing beyond manufacturer's spec.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --the tiniest sprinter
Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --the tiniest sprinter
11-14-11 | 10:33 AM
#74
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From: Los Alamos, NM
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If you hear a crack, you take the joint apart and inspect the bars. If the bars are still okay (the crack might have simply been coming from a misaligned screw), you put it back together, paying really close attention to how you tighten the bolts. You tighten until you can jump on the bars and not have them move. Like I was saying previously, the torque spec is a max, and it pertains to stripping the threads on the stem and has nothing to do with the bars.
11-14-11 | 10:42 AM
#75
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If I hear a 'crack' from a composite material, why would I put it back together? Not arguing here, but I really would like to understand the rationale that would have me continue to use a part made of CF from which I had heard cracking? I am hard-headed, but some what educatable (even if I can't spel), and would appreciate the info.
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