Aero training wheels for Clydesdale?

[artemidorus]

I've just broken my fourth rear wheel on the same bike. 3 were shallow V rims (2 x Velocity Aerohead, 1 x CXP-22), laced 3x with 32 conventional spokes to a 105 hub, and one was an R550. Each wheel bar the R550 broke multiple spokes sequentially, usually trailing drive side. I abandoned the R550 after one spoke breakage.
I want to get a bombproof deep section (>=30mm) rear wheel or wheelset, ideally 20-24 spoke (I know I could make a 36spoke wheel, but this would be my last ditch option).
Recommendations?

 

[alfeng]

I've just broken my fourth rear wheel on the same bike. 3 were shallow V rims (2 x Velocity Aerohead, 1 x CXP-22), laced 3x with 32 conventional spokes to a 105 hub, and one was an R550. Each wheel bar the R550 broke multiple spokes sequentially, usually trailing drive side. I abandoned the R550 after one spoke breakage.
I want to get a bombproof deep section (>=30mm) rear wheel or wheelset, ideally 20-24 spoke (I know I could make a 36spoke wheel, but this would be my last ditch option).
Recommendations?

Try to find a pair of older, MAVIC CXP14 rims ... they have a deeper dish (ERD == 586).

Lace them 32x4 ... with straight, 14 gauge spokes.

 

[Eden]

What about Velocity Deep V's - messengers love them around here and you know how they treat their bikes.....

 

[ScienceIsCool]

Try to find a pair of older, MAVIC CXP14 rims ... they have a deeper dish (ERD == 586).

Lace them 32x4 ... with straight, 14 gauge spokes.

CXP 14 rims should be nice and laterally stiff. But what does cross 4 lacing have to do with premature spoke failure?

Premature spoke failure that is not due to material defects is often due to either too high of a cyclical load (i.e., the spoke should have a greater cross-sectional area - bigger, fatter spokes, and/or there should be more of them) or the tension is too low. Too low of tension will cause a higher rate of fatigue for the same cyclical load.

If you are having problems with a standard 32 spoke wheel, then I would suggest a 36 spoke wheel with a well known spoke manufacturer such as DT or Sapim in a 14 or 15 Ga size. Make sure that the tension is nice and high, close to the limit of the rim.

John Swanson
www.bikephysics.com

 

[artemidorus]

I'm thinking of building a 36 spoke reserve wheel anyway, ultegra or DA hub, DT or Sapim 14/15s, radial non-drive and 3x drive side, Deep V or CXP33 rim.
I'm keen to know whether any fit, heavier (>=85kg) people have had trouble with low-spoke-count but historically reliable deep-section wheelsets such as Mavic Cosmic Carbone SL or Easton Circuit (or even Vista/SL).

 

[Phill P]

How much milage are you doing and how do you treat your wheels to be breaking so many spokes?

I'm 98kg and had good service from my 2004 Zondas. 9000kms on the front wheels and 6500kms on the rear. Had the set trued the other week after hitting un unexpected raised man hole cover at 65kph, only a slight wobble, but with 16 spokes and 98kg I didn't want to risk it next time I'm doing 65kph!!

But if you are breaking wheels go to a GOOD wheel builder, and try to get spokes that are as thick as posible at the thread and elbow, but butted inbetween.

 

[artemidorus]

How much milage are you doing and how do you treat your wheels to be breaking so many spokes?

I'm 98kg and had good service from my 2004 Zondas. 9000kms on the front wheels and 6500kms on the rear. Had the set trued the other week after hitting un unexpected raised man hole cover at 65kph, only a slight wobble, but with 16 spokes and 98kg I didn't want to risk it next time I'm doing 65kph!!

But if you are breaking wheels go to a GOOD wheel builder, and try to get spokes that are as thick as posible at the thread and elbow, but butted inbetween.

I seem to get 1500-3000km before the wheels start breaking spokes. 2 of the wheels were built by reputable builders, one by a builder said to be one of the best in the country (he recommended and used straight-gauge spokes, a decision with which I wasn't entirely happy). Other 2 were factory built. None of the spokes ever broke at a point that wasn't 14G, or bigger.
My riding is all on Sydney's "sealed" roads. I no longer ride off gutters and ride around all potholes that I spot in time. They probably do get a bit of a hammering, nevertheless.
Additionally, and as you'd expect, I only ever (I think?) break'em in my 39/25 combination - maximal torque in that one.
Those Zondas seem pretty good - do you nurse them or batter them? Correct me if I'm wrong, but you can't get them with Shimano freehubs? Is there a Fulcrum match for the Zonda?

 

[Phill P]

I don't think I batter my wheels. As you seem to do I avoid pot holes etc, and never ide off curbs etc. While I don't claim to be a A grade sprinter I probably can put out a bit of torque just to get my 98kg up the hills at the rate the smaller guys do (or as close as I can).

Campy do produce thier wheels with shimano freehubs (shimano doesn't return the favor), but the Fulcrum racing 3s are a more harmonious match if you ride don't ride campy. My wheels re the full unmachined 30mm deep rims. The newer models have lower profile machined/lighted rims, however they don't have spoke holes in the inner rim which is claimed to add rigidity back into the profile.

I don't agree that non butted spokes are stronger than butted. The point is you put extra material where the failure happens, ie the thread and the elbow which have major stress concentrations. Nearly every fatigue failure happens at these two ends. The thinner section is then less stiff and allows the rim to deflect without building as much tension in the spoke, allowing some of the neighbours to help take load. Yes the wheel is less stiff but spoked structures are meant to share load.
As far as folding a wheel goes that happens when the spokes at the bottom of a wheel loose all thier tension and hence give no lateral support. Then if there is any lateral deflection in the impact that caused the spokes to loose tension the high conpressive forces in the rim go out of balance and the rim folds itself up. If you want to avoid the spokes loosing tension you want them stretched as far as posible when building the wheel, but without too much fatigue influencing preload forces. The thin section in the spoke allows a lot of streetch without building the failure loads, and allows a large deflection in the rim before loosing all its tension.

Two reasons why butted spokes build stronger wheels than straight gauge spokes of the same max gauge.

 

[thomas_cho]

Hi Arte

Firstly my sympathies on your most recent wheel problems.

Why do you want to go low spoke count? With all the problems you are facing perhaps 36H is the only way to go. Are your breakages only on the rear wheel? What about getting a off-center rim to balance the drive and non-drive side spoke tensions?

FWIW I have built two wheelsets 32H X3 using 14G DTswiss spokes and have no issues at all.

 

[ScienceIsCool]

I'm thinking of building a 36 spoke reserve wheel anyway, ultegra or DA hub, DT or Sapim 14/15s, radial non-drive and 3x drive side, Deep V or CXP33 rim.
I'm keen to know whether any fit, heavier (>=85kg) people have had trouble with low-spoke-count but historically reliable deep-section wheelsets such as Mavic Cosmic Carbone SL or Easton Circuit (or even Vista/SL).

You know... it's possible that you've just had really bad luck. A bad batch of spokes. A "good" wheelbuilder that had a bad day and didn't stress relieve your spokes during the build process. That kind of thing.

And I agree that you should have no problems with butted spokes. The failure point for fatigue is almost always at the spoke elbow where it enters the hub. That area is usually pre-stressed from the spoke making process and is a bit of a weak link. That's why stress relieving the spoke (i.e., bending it slightly at the elbow) during the build process is so important.

John Swanson
www.bikephysics.com

 

[alfeng]

CXP 14 rims should be nice and laterally stiff. But what does cross 4 lacing have to do with premature spoke failure?

Premature spoke failure that is not due to material defects is often due to either too high of a cyclical load (i.e., the spoke should have a greater cross-sectional area - bigger, fatter spokes, and/or there should be more of them) or the tension is too low. Too low of tension will cause a higher rate of fatigue for the same cyclical load.

If you are having problems with a standard 32 spoke wheel, then I would suggest a 36 spoke wheel with a well known spoke manufacturer such as DT or Sapim in a 14 or 15 Ga size. Make sure that the tension is nice and high, close to the limit of the rim.

x4 lacing results in the force being (more) tangential ... almost 90º to the radius ... the force on the pulling spoke is therefore more "complete" rather than vectored (for want of a better description). The fact that the spokes MAY make contact with a the head of the adjacent spokes is no more a concern than the interlacing contact of the final crossing UNLESS the spokes are poorly tensioned ... that's my story, and I'm sticking to it!

 

[alfeng]

I don't think I batter my wheels. As you seem to do I avoid pot holes etc, and never ide off curbs etc. While I don't claim to be a A grade sprinter I probably can put out a bit of torque just to get my 98kg up the hills at the rate the smaller guys do (or as close as I can).

Campy do produce thier wheels with shimano freehubs (shimano doesn't return the favor), but the Fulcrum racing 3s are a more harmonious match if you ride don't ride campy. My wheels re the full unmachined 30mm deep rims. The newer models have lower profile machined/lighted rims, however they don't have spoke holes in the inner rim which is claimed to add rigidity back into the profile.

I don't agree that non butted spokes are stronger than butted. The point is you put extra material where the failure happens, ie the thread and the elbow which have major stress concentrations. Nearly every fatigue failure happens at these two ends. The thinner section is then less stiff and allows the rim to deflect without building as much tension in the spoke, allowing some of the neighbours to help take load. Yes the wheel is less stiff but spoked structures are meant to share load.
As far as folding a wheel goes that happens when the spokes at the bottom of a wheel loose all thier tension and hence give no lateral support. Then if there is any lateral deflection in the impact that caused the spokes to loose tension the high conpressive forces in the rim go out of balance and the rim folds itself up. If you want to avoid the spokes loosing tension you want them stretched as far as posible when building the wheel, but without too much fatigue influencing preload forces. The thin section in the spoke allows a lot of streetch without building the failure loads, and allows a large deflection in the rim before loosing all its tension.

Two reasons why butted spokes build stronger wheels than straight gauge spokes of the same max gauge.

I don't want to discuss the lack of benefits to a wheel built with double-butted spoke ... let me just say that a wheel built with straight gauge spokes will be laterally stiffer than a similar wheel built with double-butted spokes -- a laterally stiffer wheel is, IMO, a better wheel.

 

[ScienceIsCool]

x4 lacing results in the force being (more) tangential ... almost 90º to the radius ... the force on the pulling spoke is therefore more "complete" rather than vectored (for want of a better description). The fact that the spokes MAY make contact with a the head of the adjacent spokes is no more a concern than the interlacing contact of the final crossing UNLESS the spokes are poorly tensioned ... that's my story, and I'm sticking to it!

I'm sorry. I just don't understand your argument at all. Maybe you could try explaining it again? Regardless, none of this should have anything to do with premature spoke fatigue failures like the original post describes.

John Swanson
www.bikephysics.com

 

[alfeng]

I'm sorry. I just don't understand your argument at all. Maybe you could try explaining it again? Regardless, none of this should have anything to do with premature spoke fatigue failures like the original post describes.

John Swanson
www.bikephysics.com

That's okay -- if you get it, you get it ... if you don't, then you don't OR won't ... and, you/others have chosen to be recalictrant in the past, so why bother with an explanation, now?

ONCE MORE, INTO THE BREECH:

Just like double-butted vs. straight gauge spokes -- "I hear the words" ... but, the logic, en toto, just isn't there ... nonetheless, there are those amongst you who have chosen to religiously follow the beliefs that a double-butted spoke is stronger ... hey, it was printed in a book!

Well, for the record, I will concede that a 14/15 double-butted spoke is stronger than a straight 15g spoke, but I cannot concede that a 14/15 double-butted spoke is stronger than a straight 14g spoke ... and, I (for one), would rarely choose a straight 15g spoke (and, have NEVER chosen a 15g spoke though I think some of my older (aka "vintage") bikes came with wheels laced with spokes that are CLOSE TO that gauge, so in a pseudo-restoration I might substitute a 15g stainless steel spoke for a ~15g galvanized spoke) ... and, the double-butted 14/15 gauge spokes that I have-and/or-used were bought before-I-knew-better.

 

[alienator]

That's okay -- if you get it, you get it ... if you don't, then you don't OR won't ... and, you/others have chosen to be recalictrant in the past, so why bother with an explanation, now?

ONCE MORE, INTO THE BREECH:

Just like double-butted vs. straight gauge spokes -- "I hear the words" ... but, the logic, en toto, just isn't there ... nonetheless, there are those amongst you who have chosen to religiously follow the beliefs that a double-butted spoke is stronger ... hey, it was printed in a book!

Well, for the record, I will concede that a 14/15 double-butted spoke is stronger than a straight 15g spoke, but I cannot concede that a 14/15 double-butted spoke is stronger than a straight 14g spoke ... and, I (for one), would rarely choose a straight 15g spoke (and, have NEVER chosen a 15g spoke though I think some of my older (aka "vintage") bikes came with wheels laced with spokes that are CLOSE TO that gauge, so in a pseudo-restoration I might substitute a 15g stainless steel spoke for a ~15g galvanized spoke) ... and, the double-butted 14/15 gauge spokes that I have-and/or-used were bought before-I-knew-better.

I believe you've completely missed John's point. First, this latest response is completely off point in that it doesn't address the part of your argument that John referred to. Second, I believe John is saying that your argument is difficult to read and is difficult to make sense of because of the way it's worded, put together, or whatever. It's certainly not clear, concise, or easily understandable. It doesn't communicate well. For instance, you make the statement that the "...the force on the pulling spoke is therefore more "complete" rather than vectored (for want of a better description)." That statement is completely nonsensical. What is it supposed to mean? You are aware, aren't you, that a vector quantity is just a directed quantity, right? Force is a vector quantity. Full stop. What does completeness have to do with it? What is completeness with respect to forces? Are you attempting to use set theory to prove your point? "Complete" is completely out of place here.

The problem with arguments that have no scientific or engineering foundation, background, or whatever is that they fail when put into a scientific or engineering context. In the case of your argument, you appear to go further and insinuate that John and others are somewhow lacking something special, something telling about physical processes, something that can't be found in a science text or engineering book. Your words:

..."I hear the words" ... but, the logic, en toto, just isn't there ... nonetheless, there are those amongst you who have chosen to religiously follow the beliefs that a double-butted spoke is stronger ... hey, it was printed in a book!​

Nice. Before that you try to wield "recalcitrant" as if it gives credence to your "logic."

It seems the biggest evidence you have to support your "logic" is all of the hand waving you're doing.

 

[alfeng]

I believe you've completely missed John's point. First, this latest response is completely off point in that it doesn't address the part of your argument that John referred to. Second, I believe John is saying that your argument is difficult to read and is difficult to make sense of because of the way it's worded, put together, or whatever. It's certainly not clear, concise, or easily understandable. It doesn't communicate well. For instance, you make the statement that the "...the force on the pulling spoke is therefore more "complete" rather than vectored (for want of a better description)." That statement is completely nonsensical. What is it supposed to mean? You are aware, aren't you, that a vector quantity is just a directed quantity, right? Force is a vector quantity. Full stop. What does completeness have to do with it? What is completeness with respect to forces? Are you attempting to use set theory to prove your point? "Complete" is completely out of place here.











The problem with arguments that have no scientific or engineering foundation, background, or whatever is that they fail when put into a scientific or engineering context. In the case of your argument, you appear to go further and insinuate that John and others are somewhow lacking something special, something telling about physical processes, something that can't be found in a science text or engineering book. Your words:

..."I hear the words" ... but, the logic, en toto, just isn't there ... nonetheless, there are those amongst you who have chosen to religiously follow the beliefs that a double-butted spoke is stronger ... hey, it was printed in a book!​

Nice. Before that you try to wield "recalcitrant" as if it gives credence to your "logic."






It seems the biggest evidence you have to support your "logic" is all of the hand waving you're doing.

Okay ...

The second half of my reply was PURELY ILLUSTRATIVE -- on a point that was discussed elsewhere in the thread -- that you AR types are caught in your own little world ... it did NOT intend to address x4 lacing. I was NOT trying to expand upon x4 lacing beyond what I stated.

All of you "engineers" have the statement made which you should try to disprove ... YOU figure out the advantages/disadvantages to x4 lacing. If you don't see any advantages, then don't have any wheels laced that way.

Further, all of you who insist on double-butted spokes being better are recalcitrant regardless of whether it is being stated by me, or anyone else on the matter ... BECAUSE, you state it without foundation other than parroting what someone else has written.

BTW. Even you, Alienator, recently posted in a thread about lateral stiffness of two wheelsets you have -- do you even have a clue as to why you were actually doing the tests OR were you simply doing them because you had access to some test equipment?

Data wthout meaninginful interpretation may as well be in an undecipherable code.

BTW2. Take "more complete" to mean closer-to-100%, than otherwise ... as I indicated, I didn't want to waste the time to come up with a better explanation for you AR-types who have a problem with notions that aren't what you adhere to AT THE IMMEDIATE, GIVEN MOMENT.

Oh, and Alienator, Hutchinson makes their own tubulars despite your uninformed insistence to the contrary in an earlier thread. Sheesh. What a Maroon.

 

[ScienceIsCool]

Okay ...

The second half of my reply was PURELY ILLUSTRATIVE -- on a point that was discussed elsewhere in the thread -- that you AR types are caught in your own little world ... it did NOT intend to address x4 lacing. I was NOT trying to expand upon x4 lacing beyond what I stated.

All of you "engineers" have the statement made which you should try to disprove ... YOU figure out the advantages/disadvantages to x4 lacing. If you don't see any advantages, then don't have any wheels laced that way.

Further, all of you who insist on double-butted spokes being better are recalcitrant regardless of whether it is being stated by me, or anyone else on the matter ... BECAUSE, you state it without foundation other than parroting what someone else has written.

BTW. Even you, Alienator, recently posted in a thread about lateral stiffness of two wheelsets you have -- do you even have a clue as to why you were actually doing the tests OR were you simply doing them because you had access to some test equipment?

Data wthout meaninginful interpretation may as well be in an undecipherable code.

BTW2. Take "more complete" to mean closer-to-100%, than otherwise ... as I indicated, I didn't want to waste the time to come up with a better explanation for you AR-types who have a problem with notions that aren't what you adhere to AT THE IMMEDIATE, GIVEN MOMENT.

Oh, and Alienator, Hutchinson makes their own tubulars despite your uninformed insistence to the contrary in an earlier thread. Sheesh. What a Maroon.

Your responses have not been well reasoned. They have not been well articulated. And they have not been in agreement with well accepted principles of science and engineering.

I have politely asked you to clarify, so that I might better understand your point of view and choose to either agree or disagree based on the merits of your arguments. Instead you have been condescending, rude, and insulting. Based on all of the above, I'd recommend others not to follow your advice.

John Swanson
www.bikephysics.com

 

[alfeng]

Your responses have not been well reasoned. They have not been well articulated. And they have not been in agreement with well accepted principles of science and engineering.

I have politely asked you to clarify, so that I might better understand your point of view and choose to either agree or disagree based on the merits of your arguments. Instead you have been condescending, rude, and insulting. Based on all of the above, I'd recommend others not to follow your advice.

John Swanson
www.bikephysics.com

WOW. Well stated. I have taken the bulk of your statements to be equally arrogant, as is your nom de plume.

But, I have already digressed ...

No one has to follow what I suggest ... but, I know that your test (it was YOUR test, wasn't it?) where you used 25 lbs of weight to test wheel deflection was ludicrous ... unless the person is on a beach cruiser riding on the boardwalk, somewhere.

Go run some numbers that actually simulate something approaching real world encounters on a bicycle if YOU want some credibility.

Condescending. Damn straight. And, some of you have deserved it -- now, and in the past.

Truly, why would I waste the keyboard time trying to rationalize ANYTHING with you when you have already demonstrated repeatedly that you have no qualms about misinterpreting data?

Run some tests ... prove me wrong. OR, learn something rather than reenfocing incorrect, parroted MISinformation that you have read somewhere.

I'm not the one breaking the spokes.

 

[alienator]

The second half of my reply was PURELY ILLUSTRATIVE -- on a point that was discussed elsewhere in the thread -- that you AR types are caught in your own little world ... it did NOT intend to address x4 lacing. I was NOT trying to expand upon x4 lacing beyond what I stated.

All of you "engineers" have the statement made which you should try to disprove ... YOU figure out the advantages/disadvantages to x4 lacing. If you don't see any advantages, then don't have any wheels laced that way.

Further, all of you who insist on double-butted spokes being better are recalcitrant regardless of whether it is being stated by me, or anyone else on the matter ... BECAUSE, you state it without foundation other than parroting what someone else has written.

Why the aggression? If you can't come up with well reasoned, well communicated justifications then admit it and be done with it.

BTW. Even you, Alienator, recently posted in a thread about lateral stiffness of two wheelsets you have -- do you even have a clue as to why you were actually doing the tests OR were you simply doing them because you had access to some test equipment?

Data wthout meaninginful interpretation may as well be in an undecipherable code.

Well, only the reading challenged would think that it was me that did the tests. I said I had data. The tests were done by a well known wheel builder/wheel maker in the Western US.

Comparing lateral stiffness numbers that were measured on the same apparatus needs no interpretation: it pretty much speaks for itself. I'll givce you a hint: lateral stiffness numbers are indicative of a given wheel's lateral stiffness. Wow. Now that wasn't so undecipherable was it?

BTW2. Take "more complete" to mean closer-to-100%, than otherwise ... as I indicated, I didn't want to waste the time to come up with a better explanation for you AR-types who have a problem with notions that aren't what you adhere to AT THE IMMEDIATE, GIVEN MOMENT.

By not wanting to waste time, you mean your understanding of the topic was such that you couldn't formulate an adequate response. I understand. Using correct terms or crafting cogent arguments or reasoning has nothing to do with anal-retentiveness. It is, however, how science works. It is how things are explained. Further, it's evident, at least to everyone else here, that "time not wasted coming up with better explanations" leads directly to unintelligible, meandering thoughts, which are incapable of explaining anything to anyone.

Oh, and Alienator, Hutchinson makes their own tubulars despite your uninformed insistence to the contrary in an earlier thread. Sheesh. What a Maroon.

Veloflex makes Hutchinson, but don't feel bad that you didn't know that. Oh, and Vittoria makes Zipps tires, as well as Vredestein tires. I didn't know if you were emotionally invested as heavily with other tire makers as you are with Hutchinson. I feel honored though that you've hung on to your little Get Alienator Hutchinson Tire Nugget for so long. With the intellectual aplomb you've demonstrated, I don't think anyone holds any high expectations for you at all.

Science Guy John, your comments are spot on and sum everything up very nicely.

 

[alfeng]

Comparing lateral stiffness numbers that were measured on the same apparatus needs no interpretation: it pretty much speaks for itself. I'll givce you a hint: lateral stiffness numbers are indicative of a given wheel's lateral stiffness. Wow. Now that wasn't so undecipherable was it?

Just briefly, in THAT particular/recent thread, the WAY you wrote it made it seem as though you were amazed that the wheel with more spokes was laterally stiffer ...

Or, were you simply stupified before?