Huang on the Attack

[jpw]

http://www.cyclingnews.com/features/photos/nahbs-2013-kent-eriksen-debuts-new-full-suspension-design/253806

[pdmtong]

Too funny...

[crownjewelwl]

he calls himself the angry asian for a reason!

[pbarry]

Unless they've done their homework like Serotta did, only time will tell if the gusset will provide a suitable solution to preventing a migrating stress crack.

[Elefantino]

Can't see how it matters, other than aesthetically. School me otherwise.

[ultraman6970]

Who in the world is the huang asian guy? I got lost, thought this was about the asian road rider.

As for the hole in the tube? well... not the same do it at the 9 o'clock than at 11 o'clock position

[pbarry]

Can't see how it matters, other than aesthetically. School me otherwise.

The downtube, seat tube, and right chainstay are the most highly stressed tubes on a traditional diamond frame. Both ends of the DT can develop cracks from overheating, purge problems with TI, and bad placement of penetrations. Erikson may have done their own stress tests like Serotta did, and that reinforced weld-on may be a winner. It looks like it's in the butted range. IMO, just because a feature is on a show bike doesn't mean it will hold up in the real world.

[crownjewelwl]

Who in the world is the huang asian guy? I got lost, thought this was about the asian road rider.

As for the hole in the tube? well... not the same do it at the 9 o'clock than at 11 o'clock position

he writes a column where he complains about stuff called "the angry asian"

[Designatedbiker]

The page is no longer available

[dd74]

The page is no longer available
I just clicked on it. It's there.

[pbarry]

here it is

[dd74]

The downtube, seat tube, and right chainstay are the most highly stressed tubes on a traditional diamond frame. Both ends of the DT can develop cracks from overheating, purge problems with TI, and bad placement of penetrations. Erikson may have done their own stress tests like Serotta did, and that reinforced weld-on may be a winner. It looks like it's in the butted range. IMO, just because a feature is on a show bike doesn't mean it will hold up in the real world.
Well I guess Firefly, Independent Fabrication, Kirk, Bedford, Strong, Tommasini and Cinelli (to name a few) are going to provide a lot of frame replacements in Ti and Steel.

[pbarry]

Well I guess Firefly, Independent Fabrication, Kirk, Bedford, Strong, Tommasini and Cinelli (to name a few) are going to provide a lot of frame replacements in Ti and Steel.

How did you get there from what I wrote?? I was not casting stones, or questioning the structural integrity of anybody's bikes. Infer what you like. :beer:

[dd74]

How did you get there from what I wrote?? I was not casting stones, or questioning the structural integrity of anybody's bikes. Infer what you like. :beer:
I infer from your post which included "can develop cracks." If any of the above manufacturers provide frames that have been drilled for electrics, wouldn't you think they'd know so and make adequate precautions?

Huang is correct. There are ways to prevent/reassure against cracks and bends. More than a few builders and welders have said three holes aren't a big deal to a Ti or Steel frame.

[Elefantino]

The downtube, seat tube, and right chainstay are the most highly stressed tubes on a traditional diamond frame. Both ends of the DT can develop cracks from overheating, purge problems with TI, and bad placement of penetrations. Erikson may have done their own stress tests like Serotta did, and that reinforced weld-on may be a winner. It looks like it's in the butted range. IMO, just because a feature is on a show bike doesn't mean it will hold up in the real world.
I was looking at it from the opposite tack, as in, why does it matter if the electronic cables are routed internally at all?

[rwsaunders]

It's really no different than when you penetrate a structural steel column or horizontal member in a building, where tension and compression are involved. You calculate the size of the opening that's needed as well as the appropriate reinforcement method. I also can't imagine that the builders would incorporate this design element without the blessing of the tubing manufacturer.

[CunegoFan]

It's really no different than when you penetrate a structural steel column or horizontal member in a building, where tension and compression are involved. You calculate the size of the opening that's needed as well as the appropriate reinforcement method. I also can't imagine that the builders would incorporate this design element without the blessing of the tubing manufacturer.

Is this type of contact typical for small builders or do they just use something that looks like it will work?

[pbarry]

I infer from your post which included "can develop cracks." If any of the above manufacturers provide frames that have been drilled for electrics, wouldn't you think they'd know so and make adequate precautions?

Huang is correct. There are ways to prevent/reassure against cracks and bends. More than a few builders and welders have said three holes aren't a big deal to a Ti or Steel frame.

Yup, and Serotta has chosen to not go down that path after extensive R&D. We'll see problems or not developing from creative routing.

[BumbleBeeDave]

he calls himself the angry asian for a reason!

. . to the Caustic Asian. :eek: :rolleyes:

BBD

[Designatedbiker]

Go Huang Go! :D

[dd74]

Yup, and Serotta has chosen to not go down that path after extensive R&D. We'll see problems or not developing from creative routing.
That's true, while others at whatever extensive R&D have shown, profess the opposite of Serotta.

I look at it this way: Columbus owns Cinelli. Cinelli willingly drills their XCR frames for Di2/EPS. This could not happen if both near century old manufacturers' reputation wasn't on the line.

[dd74]

I was looking at it from the opposite tack, as in, why does it matter if the electronic cables are routed internally at all?
Tape that needs to be changed every month or so or when dirty and peeling away, ugly zip ties everywhere, wires hanging out like intestines, well, at least with EPS. Aesthetically displeasing and not to mention a potential hazard to the wiring, IMO. But it can be done.

[MadRocketSci]

when a tube bends, one side of it is in tension, the other side in compression. he looks to be putting it on the compression (top) side of the DT, which should be much less prone to crack propagation.

[dd74]

when a tube bends, one side of it is in tension, the other side in compression. he looks to be putting it on the compression (top) side of the DT, which should be much less prone to crack propagation.
I assume the opposite side of the tube (tension) is the bottom. What about a hole on the left or right side of the tube? Would those propagate cracking more so than a hole on the top?

[pbarry]

Of course it could. A buddy of mine made some good coin 20 years ago, repairing the Bianchi ti frames that had a propensity for down tube cracks near the BB. The results Serotta found after putting their frames through tens of thousands of cycles was not up to their standards. I seriously doubt anyone else has gone to those lengths. And, any retail tech who's drilling holes is voiding the OEM warranty.

Only time will tell on this subject. Let's bet a beer on the first steel or ti frame failure at one of the internal routing points. I think it will happen within 2013. :beer:

That's true, while others at whatever extensive R&D have shown, profess the opposite of Serotta.

I look at it this way: Columbus owns Cinelli. Cinelli willingly drills their XCR frames for Di2/EPS. This could not happen if both near century old manufacturers' reputation wasn't on the line.

[rwsaunders]

Is this type of contact typical for small builders or do they just use something that looks like it will work?

If you think about it, most manufactures and their distributors have technical reps...ENVE, Reynolds, Columbus, KVA, etc. who offer advice regarding the application and limitations of their tubing. The practice of placing reinforced holes in a steel bike frame (think internal cabling) is not new, and the carbon frame manufactures have addressed the cabling harness and wiring issues by essentially doing the same thing for the past few years.

I'm not a frame builder so perhaps some of the folks who post and advertise here can comment on how they make these type of design and fabrication decisions.

[MadRocketSci]

I assume the opposite side of the tube (tension) is the bottom. What about a hole on the left or right side of the tube? Would those propagate cracking more so than a hole on the top?

yeah, the bottom is in tension. but that is only considering the action when the front tire hits a bump and the whole front end moves upward. however, under hard pedaling action, the rear dropouts would push the bottom bracket forward which then stresses the DT the other way, but not as much. hard to say for sure based just on a thought experiment!

the middle of the tube on either side is where the tube should see no compression or tension due to in-plane motion, but then you have the lateral bending forces to deal with. I'm sure KE devoted some brain cells to this problem...

[firerescuefin]

yeah, the bottom is in tension. but that is only considering the action when the front tire hits a bump and the whole front end moves upward. however, under hard pedaling action, the rear dropouts would push the bottom bracket forward which then stresses the DT the other way, but not as much. hard to say for sure based just on a thought experiment!

the middle of the tube on either side is where the tube should see no compression or tension due to in-plane motion, but then you have the lateral bending forces to deal with. I'm sure KE devoted some brain cells to this problem...

Thanks for breaking that down. Perhaps you could take a swing at a couple of these questions. ;)

http://www.youtube.com/watch?v=eB5VXJXxnNU

[pbarry]

Hypothetically, if a crack were to develop, would it be noticed with Di2 and EPS like it would with a mechanical set up? With the latter, you'd notice some [usually], upshifting under hard pedaling. Without a cable in tension,[Di2 and EPS], the crack might progress until the handling was noticeably compromised. Just wondering.

[dd74]

Of course it could. A buddy of mine made some good coin 20 years ago, repairing the Bianchi ti frames that had a propensity for down tube cracks near the BB. The results Serotta found after putting their frames through tens of thousands of cycles was not up to their standards. I seriously doubt anyone else has gone to those lengths. And, any retail tech who's drilling holes is voiding the OEM warranty.

Only time will tell on this subject. Let's bet a beer on the first steel or ti frame failure at one of the internal routing points. I think it will happen within 2013. :beer:
This I completely agree with. I wouldn't even consider a drill job frame if it weren't backed with a factory warranty, which virtually all the manufacturers I mentioned above do (warranty their drilled frames).

That warranty is also the reason I believe many of these guys do some sort of R&D on their drilled frames. But beside the whole Di2/EPS drilling, what about holes for water bottle cages? I mean, if one were so concerned about compression from holes, we'd use the old style cages with an aluminum band that goes around the seat or down tube.

As well, when you look at the holes, they're drilled fairly far away from where the tubes are welded, which I would think is the most vulnerable spot on a bicycle frame.

[cfox]

How did you get there from what I wrote?? I was not casting stones, or questioning the structural integrity of anybody's bikes. Infer what you like. :beer:

This isn't edge-of-the-moment technology here. All of those builders have had bikes on the road for years now drilled for internal. My friend's (drilled for Di2) Hampsten gets the living ***** beat out of it and it's fine. My IF Ti Crown Jewel (Drilled for Di2) is fine after many bumpy miles. The builders have done their homework.

[oldpotatoe]

Unless they've done their homework like Serotta did, only time will tell if the gusset will provide a suitable solution to preventing a migrating stress crack.

I 'guess' but I've done easily 8-10 Moots Di2/EPS internal bikes..I really doubt these holes will cause failures of any kind. To imply that all the others are just drillin' holes that will lead to failures and serotta 'did their homework', I think is not quite accurate.

I think it has something to do with where serotta sources these tubes, the characteristic of said tubes and in whast form they get to the US.

[oldpotatoe]

Yup, and Serotta has chosen to not go down that path after extensive R&D. We'll see problems or not developing from creative routing.

"Extensive R&D"..what have they found that nobody else has?

..What they have shown is that they are not competitve in the electronic internal wiring frame market. Will they lose sales because of it, no doubt. Do the mentioned frame makers have pretty smart people evaluating this to make sure they don't have to warranty frames in the future, well, i'll bet they do.

I'm betting it has something to do with serotta's asian sourced titanium tubesets..but I'm just a dern bike shop owner and somebody who has about 27 years of experience in this daffy market.

You also wrote, "The results Serotta found after putting their frames through tens of thousands of cycles was not up to their standards. I seriously doubt anyone else has gone to those lengths."

I think the likes of others, who have successfully sold many thousands of frames, many with Di2/EPS 'holes', while serotta was reorganizing, sourcing these tubes for these 2 frames(proto/fondo), to make a few frames, now available, those builders probably have corporate knowledge of their frames that ben only wished he had.

serlotta aren't making Di2/EPS frames for reasons other than fear of failure. I'm thinking it is an economic decision, for a company that is trying to make a comeback.

[dd74]

They aren't making Di2/EPS frames for reasons other than fear of failure. I'm thinking it is an economic decision, for a company that is trying tyo make a comeback.
Yup, economics. Which is why they no longer build steel frames.

[cfox]

Serotta makes solid bikes, but one of their weaknesses over the years has been a righteous attitude regarding esoteric "innovations" or benefits that consumers don't really buy into, such as owning the supply chain of their carbon. It's cool that they make their own carbon, but apparently not cool enough for folks to pay an extra 4 grand for a Meivici vs a Crumpton.

[pbarry]

when a tube bends, one side of it is in tension, the other side in compression. he looks to be putting it on the compression (top) side of the DT, which should be much less prone to crack propagation.

Yes, after reading your posts, this makes sense. I'm not an engineer, but intuitively see things as working or not. That's got to be the best place for a penetration, if you absolutely must do it on the DT. Running a scalloped bead looks nice, but a round weld-on, like a beefy H20 boss, with a thick shoulder that could serve as the filler rod, would be a better solution, imo.

[pbarry]

This I completely agree with. I wouldn't even consider a drill job frame if it weren't backed with a factory warranty, which virtually all the manufacturers I mentioned above do (warranty their drilled frames).

That warranty is also the reason I believe many of these guys do some sort of R&D on their drilled frames. But beside the whole Di2/EPS drilling, what about holes for water bottle cages? I mean, if one were so concerned about compression from holes, we'd use the old style cages with an aluminum band that goes around the seat or down tube.

As well, when you look at the holes, they're drilled fairly far away from where the tubes are welded, which I would think is the most vulnerable spot on a bicycle frame.

Exactly, the H20 bosses are drilled at the least stressed points. Did Merlin go to welded H20 bosses with the Extralight? Before that, with straight guage tubing, the bosses were just holes and Riv-Nuts.

[pbarry]

I 'guess' but I've done easily 8-10 Moots Di2/EPS internal bikes..I really doubt these holes will cause failures of any kind. To imply that all the others are just drillin' holes that will lead to failures and serotta 'did their homework', I think is not quite accurate.

I think it has something to do with where serotta sources these tubes, the characteristic of said tubes and in whast form they get to the US.

When Moots sponsors a pro team on a Grand Tour, then we'll know! :) Lots of weekend warriors with low wattage output on 'em, JMO.

Here's a little story. 1991, Tour of Texas. Merlin sponsored Subaru-Montgomery, including the young LA. They'd been in business 3 or 4 years at that point. LA's bike developed a crack at the chain stay bridge and his bike got all wobbly. Eddy B., driving the team car was right there, and he got a replacement ride quickly, but not before he threw the broken bike down an embankment... Upon an autopsy, light O2 contamination was found internally at the chainstay bridge welds. 1/8" purge holes were drilled in the CS, but were not big enough. Immediately, the bit size was changed to 1/4" or 5/16". No more failures.

[Grant McLean]

Serotta makes solid bikes, but one of their weaknesses over the years has been a righteous attitude regarding esoteric "innovations" or benefits that consumers don't really buy into.

I was ordering one of the anniversary CSI frames back in the late 90s,
and I wanted a braze on front derailleur tab on my frame. Ironically,
a partial reason for my request was that I had just dealt with a friends frame
that was damaged by an over tightened front derailleur clamp.

Serotta refused to put a braze on front tab on the steel frame, said it was
unsound, the tube wasn't designed for it, and wouldn't discuss it.
I cancelled my order.

g

[pbarry]

"Extensive R&D"..what have they found that nobody else has?

..What they have shown is that they are not competitve in the electronic internal wiring frame market. Will they lose sales because of it, no doubt. Do the mentioned frame makers have pretty smart people evaluating this to make sure they don't have to warranty frames in the future, well, i'll bet they do.

I'm betting it has something to do with serotta's asian sourced titanium tubesets..but I'm just a dern bike shop owner and somebody who has about 27 years of experience in this daffy market.

You also wrote, "The results Serotta found after putting their frames through tens of thousands of cycles was not up to their standards. I seriously doubt anyone else has gone to those lengths."

I think the likes of others, who have successfully sold many thousands of frames, many with Di2/EPS 'holes', while serotta was reorganizing, sourcing these tubes for these 2 frames(proto/fondo), to make a few frames, now available, those builders probably have corporate knowledge of their frames that ben only wished he had.

They aren't making Di2/EPS frames for reasons other than fear of failure. I'm thinking it is an economic decision, for a company that is trying tyo make a comeback.

Could be. Serotta may have run more cycles and/or as a small company, they decided the failure rate was less acceptable than others with larger wallets, and didn't like the results. Every construction, from a building to a widget will fail given enough stress.

Merlin pursued the idea of manufacturing a Ti MTB bar/stem combo units in the early 90's. Rob Hendricks, [MIT engineer and later of King Cage] built the "torture device" for the bar/stem combo. Several samples failed around the 20,000 cycles stage, IIRC, and the company decided not to produce them. The results did not lead anyone to conclude that Ti was bad, or that bar/stem combos are bad, just that they weren't willing to risk their business on one product with less than stellar stress-test results.

[Grant McLean]

Merlin pursued the idea of manufacturing a Ti MTB bar/stem combo units in the early 90's. Rob Hendricks, [MIT engineer and later of King Cage] built the "torture device" for the bar/stem combo. Several samples failed around the 20,000 cycles stage, IIRC, and the company decided not to produce them.

Cannondale had a very impressive testing lab in their Bedford PA factory.
They tortured everything they spec'd as OEM on their bikes.
The engineer who gave me our tour (can't for the life of me remember his
name right now) said that a significant number of industry tests were flawed.

He could take the same part and break it 100 cycles, or make it last 1 million,
depending on how the test was rigged. It's all about simulating the real world
loads and conditions of how the part is actually stressed. Most parts are
never clamped in a way that their tests load them. It's a real art to make
these tests actually produce realistic models, which is why most of the
testing is now done on computers.

-g

[pbarry]

Cannondale had a very impressive testing lab in their Bedford PA factory.
They tortured everything they spec'd as OEM on their bikes.
The engineer who gave me our tour (can't for the life of me remember his
name right now) said that a significant number of industry tests were flawed.

He could take the same part and break it 100 cycles, or make it last 1 million,
depending on how the test was rigged. It's all about simulating the real world
loads and conditions of how the part is actually stressed. Most parts are
never clamped in a way that their tests load them. It's a real art to make
these tests actually produce realistic models, which is why most of the
testing is now done on computers.

-g
When C'dales started out in the early 80's, their bikes were the crookedest POS's ever, until they came up with a better method to bake/heat treat them. They only changed things after a few retailers took them in hand and explained how axles were breaking because the rear drop outs were miss-aligned and they could be not fixed with frame alignment tools because of the stiffness of the heat-treated AL. Another new technology with unforeseen issues.

Proof is in assessing processes in pre-production R&D and, then, how long things last in real world conditions. E-shifting is new and so are the mods made to frames so that EPS/Di2 is aesthetically pleasing. Carbon can be reinforced appropriately during manufacturing layup and fiber direction to counter the inherent weakness of a penetration. With metal, one is forced to weld or braze reinforcement at penetration points. In doing that, the additional heat fatigues the very areas that the fabricator is attempting to buttress. There's a good reason down tubes were not compromised for the first 120 years of bicycle manufacturing.

Great discussion here. Makes us all think a bit. The one thing Mavic ZAP and Mektronic wireless had over the current ES offerings was the lack of cable routing. Maybe the boys there had these same conversations?

[cfox]

There's a good reason down tubes were not compromised for the first 120 years of bicycle manufacturing.



heh? there have been braze-on/weld-on downtube shifter bosses and cable guides on steel and Ti bikes for many,many years. How about paper-thin aluminum tubed bikes with drilled then riveted downtube cable guides? All of these holes and/or welded pieces are in the same spot as a Di2 hole.

[oldpotatoe]

When Moots sponsors a pro team on a Grand Tour, then we'll know! :) Lots of weekend warriors with low wattage output on 'em, JMO.

Here's a little story. 1991, Tour of Texas. Merlin sponsored Subaru-Montgomery, including the young LA. They'd been in business 3 or 4 years at that point. LA's bike developed a crack at the chain stay bridge and his bike got all wobbly. Eddy B., driving the team car was right there, and he got a replacement ride quickly, but not before he threw the broken bike down an embankment... Upon an autopsy, light O2 contamination was found internally at the chainstay bridge welds. 1/8" purge holes were drilled in the CS, but were not big enough. Immediately, the bit size was changed to 1/4" or 5/16". No more failures.

Yep, I'm sure that's it...ohh wait, that was 22 years ago..

Look, many frame makers supply frames plumbed for electronic. I would think a carbon frame, modified for electronic, is more prone to 'failure' than a titanium one but..gee, they don't fail. It's great that you support serotta's decision to not plumb ti frames for electronic but I doubt that-

-it's a fear of failure(maybe, considering the tubes they use, but I suspect it's an economic decision, like doing away with steel. In spite of the huge resurgence of this material in the US)
-that the dozen or so other ti makers haven't done their homework.

[jpw]

I'm betting it has something to do with serotta's asian sourced titanium tubesets..


.. sourcing these tubes for these 2 frames(proto/fondo), to make a few frames, now available,


Asian tubes?

[oldpotatoe]

Asian tubes?

somebody on this forum mentioned that..if I'm wrong, well it won't be the first time.

[pbarry]

Yep, I'm sure that's it...ohh wait, that was 22 years ago..

Look, many frame makers supply frames plumbed for electronic. I would think a carbon frame, modified for electronic, is more prone to 'failure' than a titanium one but..gee, they don't fail. It's great that you support serotta's decision to not plumb ti frames for electronic but I doubt that-

-it's a fear of failure(maybe, considering the tubes they use, but I suspect it's an economic decision, like doing away with steel. In spite of the huge resurgence of this material in the US)
-that the dozen or so other ti makers haven't done their homework.

My point was that there can be a latent problem, but it may not surface for a long time. The purge problem I described was illustrating only that. It took LA's wattage to turn the purge problem into a crack. Had not happened before that.

Are any of the contemporary American steel or Ti bikes being raced by top road pros? There's great feedback available in sponsorship because of the amount of miles ridden, and stresses the equipment undergoes. Stuff either works or it doesn't, and, if not, you can find out why and change the design.

The routing methods will evolve. There were new ideas at the show, and they aren't all alike. Carbon is the easiest to reinforce, as I said earlier.


This is from an earlier thread on the same topic:


Originally Posted by jpw View Post
I don't think it will be EPS/ Di2 compatible.
The Serotta website pushes hard against the idea of drilling wiring port holes in metal frames.
Once more, a frame doesn't need to have a bunch of holes drilled it to be 'Di2/EPS 'compatible'. ANY frame is Di2/EPS compatible.

Once upon a time, a long time ago, when Di2 first came out, all were installed external and gee, you couldn't even see the wires.

[rwsaunders]

somebody on this forum mentioned that..if I'm wrong, well it won't be the first time.

I'm reading US sourced Ti from Serotta's website...

http://serotta.com/bicycles/fondo-sg

[cfox]

Carbon is the easiest to reinforce



Funny, because IF refuses to do internal wiring on their all carbon Corvid, but will do it on their metal bikes. If it were easy, I wonder why they won't do it? I'm not trying to be argumentative, but it is interesting to see viewpoints of other builders.

[pbarry]

Funny, because IF refuses to do internal wiring on their all carbon Corvid, but will do it on their metal bikes. If it were easy, I wonder why they won't do it? I'm not trying to be argumentative, but it is interesting to see viewpoints of other builders.
Good point! I was thinking of companies like CYFAC doing a complete layup moncoque design, where it would not be difficult to design and excecute IR. IF is using carbon tubes bonded to carbon lugs. Without a new lug design, any penetration would be a problem, jmo.

[jpw]

I'm reading US sourced Ti from Serotta's website...

http://serotta.com/bicycles/fondo-sg

That seems clear.

People ought to source their info.

[dd74]

Funny, because IF refuses to do internal wiring on their all carbon Corvid, but will do it on their metal bikes. If it were easy, I wonder why they won't do it? I'm not trying to be argumentative, but it is interesting to see viewpoints of other builders.
IF also refuses to drill their Factory Lightweight steel frame. I think they may have the same fears as Serotta with the thinness of the tubeset.

[cfox]

IF also refuses to drill their Factory Lightweight steel frame. I think they may have the same fears as Serotta with the thinness of the tubeset.

Not surprised; that bike has super thin tubes. They do drill the Ti Factory Lightweight; I've seen a couple Di2 internal jobs on those. Ti, esp in the non-butted tube ends, is usually pretty thick bike tube-wise.

[jpw]

http://serotta.com/2012-legend-se-electronic-routing-with-f3-fork/

:confused:

[rustylion]

You are wrong on this statement. I can't think of a reason why I would not be offering Di2/EPS frames if it was simply an economic decision. There are no constraints there for me and I could offer an option that lots of folks want. I think that would help us make customers happy(er) and sell more bikes. If it was simply economic, it would be a no-brainer.



serotta aren't making Di2/EPS frames for reasons other than fear of failure. I'm thinking it is an economic decision, for a company that is trying to make a comeback.

[rustylion]

I want to be clear that we do not design internal tests but rather we use industry standard tests established to test bicycles.

You can Google "Racing bicycles – Safety requirements and test methods, English version of DIN EN14781:2006-03" to read how we test at Poway. If we send product to an outside lab, they use the same standard although perhaps different machinery.

How many miles does the test standard equate to and is it real world? The answer to both these questions we are often asked is that we (at Serotta) probably don't know. We just depend on those that do.

Thanks.

Could be. Serotta may have run more cycles and/or as a small company, they decided the failure rate was less acceptable than others with larger wallets, and didn't like the results. Every construction, from a building to a widget will fail given enough stress.

Merlin pursued the idea of manufacturing a Ti MTB bar/stem combo units in the early 90's. Rob Hendricks, [MIT engineer and later of King Cage] built the "torture device" for the bar/stem combo. Several samples failed around the 20,000 cycles stage, IIRC, and the company decided not to produce them. The results did not lead anyone to conclude that Ti was bad, or that bar/stem combos are bad, just that they weren't willing to risk their business on one product with less than stellar stress-test results.