No longer inspecting frames for crash damage
#101
Senior Member
I suppose I did sidetrack the discussion a bit with cars.
But, a lot still applies to bikes.
One of the comments on the Corvette article claims to be by a structural engineer (but not familiar with the Vette), and he is suggesting that this part of the frame would be highly structural.
Even if a good frame could be acquired, it could be a massive undertaking to swap frames.
The circles appear to me to be some kind of a spot weld. And, I've seen other photos/videos of Corvette frames that appear to have traditional MIG/TIG welds, so the alloy is "weldable". However, I'd say that Chevrolet likely does a post heat treating of the entire frame after assembly.
Welding 6061 Aluminum is supposed to reduce strength by about 40%.
Then the question comes whether there is 40% redundancy in the frame design???
Take the car to Joe's body shop, and he'll likely jump in with MIG/TIG, have it welded up, and back on the road within an hour (assuming not too much has to be disassembled to prevent heat damage).
Take the car to a Chevy Dealer, and they won't sign off on anything short of 100% complete frame replacement with all new parts.
Now, the people buying $70,000 brand new Corvettes won't necessarily be the ones making their own backyard repairs.
And, give them a choice between a repair on someone else's dime that is "probably OK", vs "100% back to new"... and they just won't accept the "probably ok" repair.
Take away the middle-man, and make them pay up-front, and the Corvette owner may choose the cheap repair, or to attempt to hide the damage and sell it to some unsuspecting buyer.
That selling to an unsuspecting buyer may be a good reason to "brand titles" even if a vehicle is repaired.
So, as a car owner, are you satisfied with the $100 "Joe's body Shop" repair... or the massive undertaking to swap frames? Or, is nothing short of a new car acceptable?
But, a lot still applies to bikes.
One of the comments on the Corvette article claims to be by a structural engineer (but not familiar with the Vette), and he is suggesting that this part of the frame would be highly structural.
Even if a good frame could be acquired, it could be a massive undertaking to swap frames.
The circles appear to me to be some kind of a spot weld. And, I've seen other photos/videos of Corvette frames that appear to have traditional MIG/TIG welds, so the alloy is "weldable". However, I'd say that Chevrolet likely does a post heat treating of the entire frame after assembly.
Welding 6061 Aluminum is supposed to reduce strength by about 40%.
Then the question comes whether there is 40% redundancy in the frame design???
Take the car to Joe's body shop, and he'll likely jump in with MIG/TIG, have it welded up, and back on the road within an hour (assuming not too much has to be disassembled to prevent heat damage).
Take the car to a Chevy Dealer, and they won't sign off on anything short of 100% complete frame replacement with all new parts.
Now, the people buying $70,000 brand new Corvettes won't necessarily be the ones making their own backyard repairs.
And, give them a choice between a repair on someone else's dime that is "probably OK", vs "100% back to new"... and they just won't accept the "probably ok" repair.
Take away the middle-man, and make them pay up-front, and the Corvette owner may choose the cheap repair, or to attempt to hide the damage and sell it to some unsuspecting buyer.
That selling to an unsuspecting buyer may be a good reason to "brand titles" even if a vehicle is repaired.
So, as a car owner, are you satisfied with the $100 "Joe's body Shop" repair... or the massive undertaking to swap frames? Or, is nothing short of a new car acceptable?
#102
Senior Member
And, lots of model simulations to determine or correlate with formulas ("towing tanks" for ship models, "wind tunnels" for aircraft models), and static load tests. Way back then, even the aircraft companies were lacking in all the knowledge and equipment to do dynamic fatigue and vibration studies and tests, and there were mishaps due to that, catastrophic failures, or vehicles getting out of control due to divergent oscillation. And things going supersonic was/is an entirely different realm, dealing with shock waves, compressible flow, etc. Lots of crashes until things got figured out. Chuck Yeager was lucky not to crash, the plane he used to go over Mach 1 was designed all wrong for it, it was later learned.
Last edited by Duragrouch; 06-07-19 at 12:16 PM.
#103
Senior Member
If they contact the manufacturer, I assume they will in turn tell the customer to deal with the shop where it was purchased.
I assume at that point the customers only recourse is to have that shop disassemble the bike and return to the manufacturer for inspection. If it passes, it gets sent back to be reassembled. $200 all told ?. Or gets sent back for the customers choice to use/discard/fix. Or maybe a biggie like Trek pulls a “if you send to us for inspection and it fails, we destroy the frame” policy. A CYA policy.
In truth and short of ultrasound or CAT scan, X-Ray, etc.... it’s a bit of a crapshoot for a shop to inspect a carbon frame and declare it to be sound, when in reality you can’t tell what’s really going on under the paint.
I assume at that point the customers only recourse is to have that shop disassemble the bike and return to the manufacturer for inspection. If it passes, it gets sent back to be reassembled. $200 all told ?. Or gets sent back for the customers choice to use/discard/fix. Or maybe a biggie like Trek pulls a “if you send to us for inspection and it fails, we destroy the frame” policy. A CYA policy.
In truth and short of ultrasound or CAT scan, X-Ray, etc.... it’s a bit of a crapshoot for a shop to inspect a carbon frame and declare it to be sound, when in reality you can’t tell what’s really going on under the paint.
I'd do the same thing if it were my shop. Maybe that's the most honest approach than looking for a crack and pronouncing the frame good when it could be near failure.
J.
#104
Senior Member
I guess its almost impossible to determine if a frame is "as good as new" without sophisticated equipment, but its not that hard to deem it cracked with almost no equipment.
And thats pretty much what the lbs'es are trying to determine. is it a scratch or a crack? thats it. they are not trying to quantify the level of crackedness. and they dont need to. No reason to.
I feel many people are creating a storm it a drinking glass just because it made out of carbon fiber.
And its kinda funny since this is the best material in the entire universe, proven by science too. so its should not be able to break at all. right.
And thats pretty much what the lbs'es are trying to determine. is it a scratch or a crack? thats it. they are not trying to quantify the level of crackedness. and they dont need to. No reason to.
I feel many people are creating a storm it a drinking glass just because it made out of carbon fiber.
And its kinda funny since this is the best material in the entire universe, proven by science too. so its should not be able to break at all. right.
#105
Senior Member
I guess its almost impossible to determine if a frame is "as good as new" without sophisticated equipment, but its not that hard to deem it cracked with almost no equipment.
And thats pretty much what the lbs'es are trying to determine. is it a scratch or a crack? thats it. they are not trying to quantify the level of crackedness. and they dont need to. No reason to.
I feel many people are creating a storm it a drinking glass just because it made out of carbon fiber.
And its kinda funny since this is the best material in the entire universe, proven by science too. so its should not be able to break at all. right.
And thats pretty much what the lbs'es are trying to determine. is it a scratch or a crack? thats it. they are not trying to quantify the level of crackedness. and they dont need to. No reason to.
I feel many people are creating a storm it a drinking glass just because it made out of carbon fiber.
And its kinda funny since this is the best material in the entire universe, proven by science too. so its should not be able to break at all. right.
But you know how this plays out at the shop - someone brings it in, no one finds a crack but there was damage below the paint. Shop pronounces it fine and then it fails soon after and someone gets hurt. So it really is not a good thing to be doing because all the shop can say is “we didn’t find any cracks,” which isn’t really telling you anything at all. And if they tell you it’s fine, then they’re woefully ignorant; point being, they simply don’t know.
I’d respect a shop that referred you on to some one that could make the correct determination. The safety - and legal - issues are substantial.
#106
Senior Member
Yeah but if the frame is actually cracked it will most likely show up at the surface. since the surface will have to flex slightly more than the more center of the tube, since its in the periphery, bending/flexing is done more at the periphery no matter what tube shape. so its more likely its cracked at the surface and not in the "center" than the other way around. by a factor of like 3,25 million or so.
Only time i have seen stuff cracked under the surface not really showing surface damage is when there was "blunt force truma" and then sometimes the paint is so flexible so it follows the cracked carbon (not very likely though) without indicating any damage. but if you simply squeeze this part it will definitely show up as delamiated. since its soft and weak there. and there will always be some sign of it. otherwise the damage wouldn't have happened in the first place. you just have to be looking carefully. I dont usually work with carbon but i do look for cracks and similar all day long at my job.
I understand they shops want their backs free. but what about the customer??
if you were to send in a scratched frame to the lbs and they send it away. its like 50% chance you wont ever get it back and you will never know why. And i kinda doubt the manufacturers local offices are set up for any kind of hitech non destructive testing. I'm guessing they are just as good as the lbs for determining this.
I however am very proficient in destructive and non destructive testing of anything.
I have have been trained/educated in a fighter plane factory by some of the best carbon guys on this planet, from the lab, so i feel 100% confident inspecting stuff myself. Not all people may be like that though.
Only time i have seen stuff cracked under the surface not really showing surface damage is when there was "blunt force truma" and then sometimes the paint is so flexible so it follows the cracked carbon (not very likely though) without indicating any damage. but if you simply squeeze this part it will definitely show up as delamiated. since its soft and weak there. and there will always be some sign of it. otherwise the damage wouldn't have happened in the first place. you just have to be looking carefully. I dont usually work with carbon but i do look for cracks and similar all day long at my job.
I understand they shops want their backs free. but what about the customer??
if you were to send in a scratched frame to the lbs and they send it away. its like 50% chance you wont ever get it back and you will never know why. And i kinda doubt the manufacturers local offices are set up for any kind of hitech non destructive testing. I'm guessing they are just as good as the lbs for determining this.
I however am very proficient in destructive and non destructive testing of anything.
I have have been trained/educated in a fighter plane factory by some of the best carbon guys on this planet, from the lab, so i feel 100% confident inspecting stuff myself. Not all people may be like that though.
#107
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Is a brand new frame inspected by an LBS for damage and certified problem-free? After all, it went thru probably multiple shipments (from frame building plant to assembly plant, then all the way oversees in a container to a distributor, then maybe to the LBS. Who knows what goes on in transit and handling
#108
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Yeah but if the frame is actually cracked it will most likely show up at the surface. since the surface will have to flex slightly more than the more center of the tube, since its in the periphery, bending/flexing is done more at the periphery no matter what tube shape. so its more likely its cracked at the surface and not in the "center" than the other way around. by a factor of like 3,25 million or so.
Only time i have seen stuff cracked under the surface not really showing surface damage is when there was "blunt force truma" and then sometimes the paint is so flexible so it follows the cracked carbon (not very likely though) without indicating any damage. but if you simply squeeze this part it will definitely show up as delamiated. since its soft and weak there. and there will always be some sign of it. otherwise the damage wouldn't have happened in the first place. you just have to be looking carefully. I dont usually work with carbon but i do look for cracks and similar all day long at my job.
I understand they shops want their backs free. but what about the customer??
if you were to send in a scratched frame to the lbs and they send it away. its like 50% chance you wont ever get it back and you will never know why. And i kinda doubt the manufacturers local offices are set up for any kind of hitech non destructive testing. I'm guessing they are just as good as the lbs for determining this.
I however am very proficient in destructive and non destructive testing of anything.
I have have been trained/educated in a fighter plane factory by some of the best carbon guys on this planet, from the lab, so i feel 100% confident inspecting stuff myself. Not all people may be like that though.
Only time i have seen stuff cracked under the surface not really showing surface damage is when there was "blunt force truma" and then sometimes the paint is so flexible so it follows the cracked carbon (not very likely though) without indicating any damage. but if you simply squeeze this part it will definitely show up as delamiated. since its soft and weak there. and there will always be some sign of it. otherwise the damage wouldn't have happened in the first place. you just have to be looking carefully. I dont usually work with carbon but i do look for cracks and similar all day long at my job.
I understand they shops want their backs free. but what about the customer??
if you were to send in a scratched frame to the lbs and they send it away. its like 50% chance you wont ever get it back and you will never know why. And i kinda doubt the manufacturers local offices are set up for any kind of hitech non destructive testing. I'm guessing they are just as good as the lbs for determining this.
I however am very proficient in destructive and non destructive testing of anything.
I have have been trained/educated in a fighter plane factory by some of the best carbon guys on this planet, from the lab, so i feel 100% confident inspecting stuff myself. Not all people may be like that though.
#109
Senior Member
Is a brand new frame inspected by an LBS for damage and certified problem-free? After all, it went thru probably multiple shipments (from frame building plant to assembly plant, then all the way oversees in a container to a distributor, then maybe to the LBS. Who knows what goes on in transit and handling
If you look on youtube, there is a an australian guy, that does carbon repairs. I'm guessing he is one of the best ones on this planet. and sometimes he cuts open frames that have been deemed beyond repair, he has to destroy them so he simply slice them open. in 2 halves.
https://www.youtube.com/channel/UCY9..._zbIedQ/videos
Luescher Teknik
He also slice open rims and forks and handlebars iirc.
much gold in there imo.
you be the judge.
#110
Senior Member
The crack will not always show on the surface because a carbon tube in a frame is not usually of homogeneous composition. Internal fibres can be running in different directions to external ones, thus experiencing different loads and points of failure. They may also be a different carbon with a different modulus of rigidity, again causing different loading throughout the tube wall.
so if its gonna crack. its not gonna do so from the inside. not a tube that you flex. not gonna happen but you might try to convince me, and its not gonna end up well for you. and not for anyone else with a brain. I'm friends that have been designing and building with carbon since 1985 or so. they design the molds and do QC of the parts.
I really have no horse in the race though since i own 0 carbon bikes. i do own 3 steel and 2 Ti bikes though. and those are dependable materials. if they crack you will know. you can spot it from 1meter away.
god luck with your crabon frame man!
#111
Senior Member
I dont exactly expect the guys in italy that brazed my frames to outlive me. but they knew the risks and made their choices. thats how it works. but not in china it doesn't. I dont however feel sorry for them. i dont buy stuff from china so i dont contribute to their early demise. my conscience is clean.
no one died for my frames to be built.
no one died for my frames to be built.
Last edited by carlos danger; 06-08-19 at 06:28 PM.
#112
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I dont exactly expect the guys in italy that brazed my frames to outlive me. but they knew the risks and made their choices. thats how it works. but not in china it doesn't. I dont however feel sorry for them. i dont buy stuff from china so i dont contribute to their early demise. my conscience is clean.
no one died for my frames to be built.
no one died for my frames to be built.
#113
Pizzaiolo Americano
the exact same way as you or i would obvioulsly.
you see a line, then try to make the line wider.. does it get wider with force? yeah, then its cracked.
maybe push your finger into the "line" and see if there is some kind of movement there.
I sometimes wonder if the whole of humanity suddenly went completely nuts.
If you were to present this "problem" to people living in the 50ies, in the US. I'm fairly certain they would have solved it in like 1 minute. just like me. carbon is no different to other frame materials when searching for suspected cracks imo.
But people are afraid of carbon. they don't want to touch the holy carbon, made by the taiwan mass production buddhas.
I'd say if anyone human can make it then anyone human can inspect and determine if its shot. easy as that. and it actually is easy as that.
you see a line, then try to make the line wider.. does it get wider with force? yeah, then its cracked.
maybe push your finger into the "line" and see if there is some kind of movement there.
I sometimes wonder if the whole of humanity suddenly went completely nuts.
If you were to present this "problem" to people living in the 50ies, in the US. I'm fairly certain they would have solved it in like 1 minute. just like me. carbon is no different to other frame materials when searching for suspected cracks imo.
But people are afraid of carbon. they don't want to touch the holy carbon, made by the taiwan mass production buddhas.
I'd say if anyone human can make it then anyone human can inspect and determine if its shot. easy as that. and it actually is easy as that.
Last edited by Pizzaiolo Americano; 06-09-19 at 01:42 AM.
#114
Pizzaiolo Americano
yes fibers running in all directions is the norm, otherwise carbon fiber does not work at all. even though all cabron fibers are all different modulus (stiffness) and strength they are for all practical purposes rock hard. and unrigid.
so if its gonna crack. its not gonna do so from the inside. not a tube that you flex. not gonna happen but you might try to convince me, and its not gonna end up well for you. and not for anyone else with a brain. I'm friends that have been designing and building with carbon since 1985 or so. they design the molds and do QC of the parts.
I really have no horse in the race though since i own 0 carbon bikes. i do own 3 steel and 2 Ti bikes though. and those are dependable materials. if they crack you will know. you can spot it from 1meter away.
god luck with your crabon frame man!
so if its gonna crack. its not gonna do so from the inside. not a tube that you flex. not gonna happen but you might try to convince me, and its not gonna end up well for you. and not for anyone else with a brain. I'm friends that have been designing and building with carbon since 1985 or so. they design the molds and do QC of the parts.
I really have no horse in the race though since i own 0 carbon bikes. i do own 3 steel and 2 Ti bikes though. and those are dependable materials. if they crack you will know. you can spot it from 1meter away.
god luck with your crabon frame man!
#115
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I understand there are a number of high tech and quite expensive methods of investigating the structural integrity of composites, which provide more information for an engineer to make a theoretical assessment.
But someone without the inclination or means to afford such techniques can perform a practical assessment to a pretty reasonable degree of confidence, albeit insufficient for legal purposes.
In addition to the usual visual and tap and squeeze inspection, do the following:
Put the front wheel against a wall and give it a shove. Lean the bike over with the brakes on and stand on each pedal, give it a bounce. Put both wheels against the base of a wall, a hand each on seat and stem, and twist the frame. Put both hands on the seat, bend over so your belly is resting on your hands, and shove down. Any bike worth half a damn, except perhaps a tiny handful of bespoke ultimate weight weenie machines, can easily withstand such tests from all but the brawniest dudes.
Demonstrate the tests on the lightest bike in the shop first, tell the customer how any bike should be strong enough to survive such tests, and if their bike doesn't, you've saved them from it failing underneath them. If the bike passes without making any creaks, it should be good to go, but you can't give the customer a guarantee; all they have is witnessing the frame withstand forces extreme enough to simulate pretty much anything it'll cop during a ride, and the decision to trust it is up to them. If it does creak, try to eliminate the usual suspects before testing again, because that's probably more likely than frame damage.
Even if the frame has visible damage, depending on how overbuilt it is, it could still be serviceable. I have an '08 Tarmac I scored for free because it has a bit of impact damage above the FD. There's a crack maybe half an inch long across the right side of the tube, but because it's a relatively heavy frame at 1.2kg, there's plenty of redundancy, and I can't get a sound out of it. Theoretically, stiffness is compromised, and asymmetrically at that, but it's undetectable via seat of the pants. Been riding it for years without any visible change in the crack.
Carbon is bloody strong stuff. If in doubt, try to break it. If you can't break it by hand using leverage and all your strength, do you think it's suddenly going to fail when you're riding it?
But someone without the inclination or means to afford such techniques can perform a practical assessment to a pretty reasonable degree of confidence, albeit insufficient for legal purposes.
Put the front wheel against a wall and give it a shove. Lean the bike over with the brakes on and stand on each pedal, give it a bounce. Put both wheels against the base of a wall, a hand each on seat and stem, and twist the frame. Put both hands on the seat, bend over so your belly is resting on your hands, and shove down. Any bike worth half a damn, except perhaps a tiny handful of bespoke ultimate weight weenie machines, can easily withstand such tests from all but the brawniest dudes.
Demonstrate the tests on the lightest bike in the shop first, tell the customer how any bike should be strong enough to survive such tests, and if their bike doesn't, you've saved them from it failing underneath them. If the bike passes without making any creaks, it should be good to go, but you can't give the customer a guarantee; all they have is witnessing the frame withstand forces extreme enough to simulate pretty much anything it'll cop during a ride, and the decision to trust it is up to them. If it does creak, try to eliminate the usual suspects before testing again, because that's probably more likely than frame damage.
Even if the frame has visible damage, depending on how overbuilt it is, it could still be serviceable. I have an '08 Tarmac I scored for free because it has a bit of impact damage above the FD. There's a crack maybe half an inch long across the right side of the tube, but because it's a relatively heavy frame at 1.2kg, there's plenty of redundancy, and I can't get a sound out of it. Theoretically, stiffness is compromised, and asymmetrically at that, but it's undetectable via seat of the pants. Been riding it for years without any visible change in the crack.
Carbon is bloody strong stuff. If in doubt, try to break it. If you can't break it by hand using leverage and all your strength, do you think it's suddenly going to fail when you're riding it?
#116
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I understand there are a number of high tech and quite expensive methods of investigating the structural integrity of composites, which provide more information for an engineer to make a theoretical assessment.
But someone without the inclination or means to afford such techniques can perform a practical assessment to a pretty reasonable degree of confidence, albeit insufficient for legal purposes.
But someone without the inclination or means to afford such techniques can perform a practical assessment to a pretty reasonable degree of confidence, albeit insufficient for legal purposes.
#117
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I understand there are a number of high tech and quite expensive methods of investigating the structural integrity of composites, which provide more information for an engineer to make a theoretical assessment.
But someone without the inclination or means to afford such techniques can perform a practical assessment to a pretty reasonable degree of confidence, albeit insufficient for legal purposes.
In addition to the usual visual and tap and squeeze inspection, do the following:
Put the front wheel against a wall and give it a shove. Lean the bike over with the brakes on and stand on each pedal, give it a bounce. Put both wheels against the base of a wall, a hand each on seat and stem, and twist the frame. Put both hands on the seat, bend over so your belly is resting on your hands, and shove down. Any bike worth half a damn, except perhaps a tiny handful of bespoke ultimate weight weenie machines, can easily withstand such tests from all but the brawniest dudes.
Demonstrate the tests on the lightest bike in the shop first, tell the customer how any bike should be strong enough to survive such tests, and if their bike doesn't, you've saved them from it failing underneath them. If the bike passes without making any creaks, it should be good to go, but you can't give the customer a guarantee; all they have is witnessing the frame withstand forces extreme enough to simulate pretty much anything it'll cop during a ride, and the decision to trust it is up to them. If it does creak, try to eliminate the usual suspects before testing again, because that's probably more likely than frame damage.
Even if the frame has visible damage, depending on how overbuilt it is, it could still be serviceable. I have an '08 Tarmac I scored for free because it has a bit of impact damage above the FD. There's a crack maybe half an inch long across the right side of the tube, but because it's a relatively heavy frame at 1.2kg, there's plenty of redundancy, and I can't get a sound out of it. Theoretically, stiffness is compromised, and asymmetrically at that, but it's undetectable via seat of the pants. Been riding it for years without any visible change in the crack.
Carbon is bloody strong stuff. If in doubt, try to break it. If you can't break it by hand using leverage and all your strength, do you think it's suddenly going to fail when you're riding it?
But someone without the inclination or means to afford such techniques can perform a practical assessment to a pretty reasonable degree of confidence, albeit insufficient for legal purposes.
In addition to the usual visual and tap and squeeze inspection, do the following:
Put the front wheel against a wall and give it a shove. Lean the bike over with the brakes on and stand on each pedal, give it a bounce. Put both wheels against the base of a wall, a hand each on seat and stem, and twist the frame. Put both hands on the seat, bend over so your belly is resting on your hands, and shove down. Any bike worth half a damn, except perhaps a tiny handful of bespoke ultimate weight weenie machines, can easily withstand such tests from all but the brawniest dudes.
Demonstrate the tests on the lightest bike in the shop first, tell the customer how any bike should be strong enough to survive such tests, and if their bike doesn't, you've saved them from it failing underneath them. If the bike passes without making any creaks, it should be good to go, but you can't give the customer a guarantee; all they have is witnessing the frame withstand forces extreme enough to simulate pretty much anything it'll cop during a ride, and the decision to trust it is up to them. If it does creak, try to eliminate the usual suspects before testing again, because that's probably more likely than frame damage.
Even if the frame has visible damage, depending on how overbuilt it is, it could still be serviceable. I have an '08 Tarmac I scored for free because it has a bit of impact damage above the FD. There's a crack maybe half an inch long across the right side of the tube, but because it's a relatively heavy frame at 1.2kg, there's plenty of redundancy, and I can't get a sound out of it. Theoretically, stiffness is compromised, and asymmetrically at that, but it's undetectable via seat of the pants. Been riding it for years without any visible change in the crack.
Carbon is bloody strong stuff. If in doubt, try to break it. If you can't break it by hand using leverage and all your strength, do you think it's suddenly going to fail when you're riding it?
I don't think you could or would want to by the sort of tests you described, but yet this is exactly the sort of situation that you would expect your bike to withstand and not collapse beneath you.
#118
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And you are proud of this?
of course you should inspect frames. and charge the customer accordingly.
Sure you can only do a visual inpection, but you should still do it. Because if the "customer" comes to you he is even more clueless than you are.
And he is the person you make your money from!! so do you want to alienate your money stream?
of course you should inspect frames. and charge the customer accordingly.
Sure you can only do a visual inpection, but you should still do it. Because if the "customer" comes to you he is even more clueless than you are.
And he is the person you make your money from!! so do you want to alienate your money stream?
Sounds reasonable not to inspect.
#119
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Seems like a smart move to stay in business. Too much liability involved even if you don't have anything in writing, all I guy has to do is show a receipt that he paid for an inspection and state the bike shop stated it was okay to ride in court. That guy will own your business after the suit. More I read this thread about steel rusting through and carbon bikes failing, the more I gravitate towards Titanium as the best material for cycling. Brush Ti also looks better than carbon, painted steel/aluminum, etc. as well.
#120
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Seems like a smart move to stay in business. Too much liability involved even if you don't have anything in writing, all I guy has to do is show a receipt that he paid for an inspection and state the bike shop stated it was okay to ride in court. That guy will own your business after the suit. More I read this thread about steel rusting through and carbon bikes failing, the more I gravitate towards Titanium as the best material for cycling. Brush Ti also looks better than carbon, painted steel/aluminum, etc. as well.
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I am not sure that would be the case, necessarily. If one were to come in to have the front end checked for damage and then a week later the front end failed, it wouldn’t be a hard stretch to say the shop missed it. Civil cases have a lower bar of proof. More than likely, if the shop tried to say that the damage occurred after the inspection, they would have to somehow prove that through photos or something. Most insurance companies would rather not go to court, so they would more than likely go for an out of court settlement.
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Do you think you can simulate the sort of forces a frame/fork would experience from hitting a substantial pot hole?
I don't think you could or would want to by the sort of tests you described, but yet this is exactly the sort of situation that you would expect your bike to withstand and not collapse beneath you.
I don't think you could or would want to by the sort of tests you described, but yet this is exactly the sort of situation that you would expect your bike to withstand and not collapse beneath you.
Reasonable from one angle, but many folks will ask if there's an angle you can take that gives them at least part of what they came for. You can take some money for your time, but make it clear the decision to use the bike is up to the customer. You'd only be giving them something more to base their decision on, not pronouncing the bike sound.
#123
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I am not sure that would be the case, necessarily. If one were to come in to have the front end checked for damage and then a week later the front end failed, it wouldn’t be a hard stretch to say the shop missed it. Civil cases have a lower bar of proof. More than likely, if the shop tried to say that the damage occurred after the inspection, they would have to somehow prove that through photos or something. Most insurance companies would rather not go to court, so they would more than likely go for an out of court settlement.
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Reasonable from one angle, but many folks will ask if there's an angle you can take that gives them at least part of what they came for. You can take some money for your time, but make it clear the decision to use the bike is up to the customer. You'd only be giving them something more to base their decision on, not pronouncing the bike sound.
Reasonable from one angle, but many folks will ask if there's an angle you can take that gives them at least part of what they came for. You can take some money for your time, but make it clear the decision to use the bike is up to the customer. You'd only be giving them something more to base their decision on, not pronouncing the bike sound.
Same for an adult - unless adult was willing to sign something saying they would not hold the shop liable for their opinion, which would still be risky I think, I'd avoid the issue.
I am not an attorney, not an attorney spokes person, but I have watched a bunch of Boston Legal before it got really weird.
#125
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Timely and detailed response on carbon frame damage from Lennard Zinn. His point: you can’t visually inspect a carbon frame and know if it’s good.
https://www.velonews.com/2019/06/tec...storage_494508
https://www.velonews.com/2019/06/tec...storage_494508