Wheel Set for Heavy Guy
#52
Thread Killer
Join Date: Aug 2008
Location: Ann Arbor, MI
Posts: 12,373
Bikes: 15 Kinesis Racelight 4S, 76 Motebecane Gran Jubilée, 17 Dedacciai Gladiatore2, 12 Breezer Venturi, 09 Dahon Mariner, 12 Mercier Nano, 95 DeKerf Team SL, 19 Tern Rally, 21 Breezer Doppler Cafe+, 19 T-Lab X3, 91 Serotta CII
Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 3078 Post(s)
Liked 1,631 Times
in
1,005 Posts
Man, am I glad I entered the online world at the tail end of Brandt's activity period, because I think that guy was just not credible on so much, and I know we'd have butted heads a lot.
#53
Speechless
Join Date: Jun 2011
Location: Central NY
Posts: 8,842
Bikes: Felt Brougham, Lotus Prestige, Cinelli Xperience,
Mentioned: 22 Post(s)
Tagged: 1 Thread(s)
Quoted: 163 Post(s)
Likes: 0
Liked 39 Times
in
16 Posts
No engineering principal support this myth. In fact, quite the opposite, a thinner spoke flexes the wheel system more and will cause the wheel to go out of true more easily. It can be proven through simple superposition or by computer simulation and has been.
If you want/need a strong/stiffer wheel, go with 2.0 straight gauge over butted 2.0/1.8. It's the law!
If you want/need a strong/stiffer wheel, go with 2.0 straight gauge over butted 2.0/1.8. It's the law!
1. A wheel goes out of true for a spoke related issue for only two reasons: the spoke sees plastic deformation or nipple unscrews. Either spoke can make a wheel free from these conditions if built properly.
2. A 2.0mm 14 gauge straight spoke has 23% more area than a 2.0/1.8mm spoke, but 15-20% less ultimate strength. Straight gauge spokes do not have the work hardening benefits of the butted spoke. Real load carrying capacity is very similar between the two.
3. By your superposition argument, a 3.0mm spoke would be stronger than a 2.0mm, a 6.0mm stronger still, and a solid steel wheel strongest yet. But every first year statics class teaches you to solve the problem at hand, to the specified factor of safety. My statics teacher sought the answer that meant using the least amount of material that meets or exceeds the design parameters. So the true question for spokes is are they strong enough? In my experience and exposure, 2.0/1.8mm spokes, in the right quantity, can build wheels that will remain true to the expected duty cycle.
Also note, I have no experience with Sapim Lasers (2.0/1.5mm), but those things seem pretty damn flimsy to me.
Again, no discourtesy intended, only civil discussion.
#54
afraid of whales
Join Date: Apr 2009
Location: Front Range, CO
Posts: 4,306
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 347 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
rpenmanparker, Where are your results to make such a claim? No empirical or theoretical explanation supports such a claim.
This statement doesn't have any foundation in engineering. More flex causes fatigue, fatigue leads to failure. A stiffer wheel flexes less and is more resistant to permanent deflections. Telling a Clyde to use double butted spokes so the wheel will "better" is wrong and not rooted in any engineering principals. The simplest engineering explanation is the engineering principal of superposition. A wheel is a linear system, superposition applies. Others have run computer simulation to get the same result.
Superposition: google is your friend:
Superposition principle - Wikipedia, the free encyclopedia
Superposition: google is your friend:
Superposition principle - Wikipedia, the free encyclopedia
Last edited by Mr IGH; 05-01-15 at 01:51 PM.
#56
afraid of whales
Join Date: Apr 2009
Location: Front Range, CO
Posts: 4,306
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 347 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
The subject is about a clyde wheel, that's why I chimed in. I'm 220lbs and I use DB spokes on my roadie wheels because they ride nicer. But on my touring bike and dual suspension 29'er it's straight gauge all the way.
Last edited by Mr IGH; 05-01-15 at 01:48 PM.
#57
Speechless
Join Date: Jun 2011
Location: Central NY
Posts: 8,842
Bikes: Felt Brougham, Lotus Prestige, Cinelli Xperience,
Mentioned: 22 Post(s)
Tagged: 1 Thread(s)
Quoted: 163 Post(s)
Likes: 0
Liked 39 Times
in
16 Posts
As a Clyde with many wheelsets, I can't remember ever cursing at the overbuilt ones...
#58
afraid of whales
Join Date: Apr 2009
Location: Front Range, CO
Posts: 4,306
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 347 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
I presented my questions about his claims to him in person, at the Palo Alto Bike Shop in the fall of 1986. I had read his book and asked/challenged him about "standing on a spoke" claim and the "DB is gooder" claim. He was kinda speechless, I guess he wasn't used to defending his claims. To this day, he's never given any engineering explanation beyond what's in the book. I've since met a fellow rider/engineer and he had the same result using finite analysis, Josbt got all pissed at him too. Never defended his claims, just attacked him (just as he did to me in '86).
#60
L-I-V-I-N
Join Date: May 2005
Location: Stafford, OR
Posts: 4,801
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
rp, unless you also can post a Wikipedia link...I might have to side with Mr IGH.
__________________
"The older you do get, the more rules they're gonna try to get you to follow. You just gotta keep livin', man, L-I-V-I-N." - Wooderson
'14 carbon Synapse - '12 CAAD 10 5 - '99 Gary Fisher Big Sur
"The older you do get, the more rules they're gonna try to get you to follow. You just gotta keep livin', man, L-I-V-I-N." - Wooderson
'14 carbon Synapse - '12 CAAD 10 5 - '99 Gary Fisher Big Sur
#61
Senior Member
Join Date: Dec 2009
Location: Houston, TX
Posts: 28,682
Bikes: 1990 Romic Reynolds 531 custom build, Merlin Works CR Ti custom build, super light Workswell 066 custom build
Mentioned: 109 Post(s)
Tagged: 1 Thread(s)
Quoted: 6556 Post(s)
Likes: 0
Liked 58 Times
in
36 Posts
Ya gotta do whatcha gotta do. But I'm sticking with Brandt. He has been too reliable for me to abandon him based on internet chatter.
#62
Senior Member
Shimano RS11
#63
afraid of whales
Join Date: Apr 2009
Location: Front Range, CO
Posts: 4,306
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 347 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
"Internet chatter", LOL. One thing you can be proud of is that neither you or Josbt knows what superposition is or how to apply it to real world engineering tasks, ironic!
#64
Thread Killer
Join Date: Aug 2008
Location: Ann Arbor, MI
Posts: 12,373
Bikes: 15 Kinesis Racelight 4S, 76 Motebecane Gran Jubilée, 17 Dedacciai Gladiatore2, 12 Breezer Venturi, 09 Dahon Mariner, 12 Mercier Nano, 95 DeKerf Team SL, 19 Tern Rally, 21 Breezer Doppler Cafe+, 19 T-Lab X3, 91 Serotta CII
Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 3078 Post(s)
Liked 1,631 Times
in
1,005 Posts
I presented my questions about his claims to him in person, at the Palo Alto Bike Shop in the fall of 1986. I had read his book and asked/challenged him about "standing on a spoke" claim and the "DB is gooder" claim. He was kinda speechless, I guess he wasn't used to defending his claims. To this day, he's never given any engineering explanation beyond what's in the book. I've since met a fellow rider/engineer and he had the same result using finite analysis, Josbt got all pissed at him too. Never defended his claims, just attacked him (just as he did to me in '86).
Anyway, I wrote him off as a pseudo-scientific retrogrouch blowhard long ago...probably after reading my second issue of Bicycle Quarterly!
#65
afraid of whales
Join Date: Apr 2009
Location: Front Range, CO
Posts: 4,306
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 347 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
No, I only spoke with him that one time. I'm a professional, degreed engineer, I recognize a BS' er as part of my job. Thankfully I didn't have to waste any time on him, there's no need to, not being paid to fix that kinda stupid.
#66
Senior Member
Join Date: Dec 2009
Location: Houston, TX
Posts: 28,682
Bikes: 1990 Romic Reynolds 531 custom build, Merlin Works CR Ti custom build, super light Workswell 066 custom build
Mentioned: 109 Post(s)
Tagged: 1 Thread(s)
Quoted: 6556 Post(s)
Likes: 0
Liked 58 Times
in
36 Posts
But getting back to the nitty gritty of this discussion you cannot discredit Brandt's position by a "he said, he said" argument. If you want to challenge his teaching on the basis of its lack of factual support, you have to bring forward your own details. You can't reasonably call him out for showing no evidence on the basis of your doing exactly the same thing. I am open to considering your argument, but you have to show it to me. And saying that some other unnamed engineer agrees with you just doesn't cut it. Either you make the argument or you don't. In the absence of a better representation of your position, a well-regarded authority like Brandt has to win. And the fact that he can frequently be a pompous ass really doesn't nullify his technical achievements. In the scientific publishing community, BS like you are talking just lands in the circular file.
Last edited by rpenmanparker; 05-02-15 at 08:38 AM.
#67
afraid of whales
Join Date: Apr 2009
Location: Front Range, CO
Posts: 4,306
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 347 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
I already made the argument, any trained engineer understands it (though in my experience it seems only mechanical and electrical engineers understand engineering superposition and how to use it). Not every engineering concept is able to be understood by a layperson...and for josbt being highly regarded, that is an opinion that many trained engineers would dispute....
#68
Senior Member
Join Date: Aug 2010
Location: Southern California
Posts: 588
Bikes: Gary Fisher Hi-Fi Deluxe, Giant Stance, Cannondale Synapse, Diamondback 8sp IGH, 1989 Merckx
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 51 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
230# + bike = 260# ready to ride. My wheel set is a Shimano RS10 with 16/20 spokes.
4K or so miles with no problems. None. However, I've never hit a pothole, jumped a curb or anything like that. The roads around here are smooth. If I were to consider another set of wheels it would be the Shimano Ultegra 6800s because they are lighter. I have enormous respect for Shimano's engineering and construction quality; their wheels are superb.
I plan on building a loaded tourer starting with a Surly Disc Trucker frame. I'll use Shimano MTB wheels for that.
I have a lot of experience in the motorcycle world including their wheels. Before motorcycles, I studied, built & tuned bicycle wheels. My experience indicates that broken spokes are almost always a result of flexing at the elbow of the 'J' bend. This flexing, in turn, is due to loose spokes. By loose I mean that the spoke elbow can and does move in the hub's spoke hole causing large peak loads that can quickly fatigue an already stressed and perhaps weakened part of the spoke.
A sufficiently tensioned wheel does not allow relative movement between the spoke head (elbow/J-bend) and the spoke hole and its spokes do not break.
Harley-Davidson uses J-bend spokes and has had more than a little trouble with their aluminum-hubed wheels breaking them. First, they were not tensioning the spokes enough to prevent load cycling movement and, secondly, the soft alloy hubs were deforming around the spoke holes such that the spokes were losing tension. They never had this problem with their old steel hubs.
On the other hand, I have never, ever seen a BMW with loose spokes, never had to true one and I have been working on them for more than fifty years. All BMW wheels use straight spokes with no bends (we used to call them 'nail-head' spokes). All BMW wheels use aluminum hubs and rims. All of them have (or had) a small steel reinforcing plate between the spoke head and hub. They are the most reliable motorcycle wheels I know of.
I do not believe that my 16/20-spoked wheels would carry my fat (230#) ass around if they were made with J-bend spokes. In any case, I have no intention of personally discovering the truth of the matter. If I wish to add flex to my wheels, I'll do it with spoke diameter selection and cross pattern, not wiggling the J-bend in a hub's spoke hole. Straight spokes are superior to those with bent ends in a couple of ways, but, are not versatile. Straight spokes cannot be mixed and matched between hubs & rims; the hubs, rims and spokes must be machined to fit together.
Joe
Oh Yeah, regarding Jobst: He got most things right but not all. I can't understand how he thinks gyroscopic forces have little more than a minor roll in bicycle stability. He was occasionally bone-headed.
4K or so miles with no problems. None. However, I've never hit a pothole, jumped a curb or anything like that. The roads around here are smooth. If I were to consider another set of wheels it would be the Shimano Ultegra 6800s because they are lighter. I have enormous respect for Shimano's engineering and construction quality; their wheels are superb.
I plan on building a loaded tourer starting with a Surly Disc Trucker frame. I'll use Shimano MTB wheels for that.
I have a lot of experience in the motorcycle world including their wheels. Before motorcycles, I studied, built & tuned bicycle wheels. My experience indicates that broken spokes are almost always a result of flexing at the elbow of the 'J' bend. This flexing, in turn, is due to loose spokes. By loose I mean that the spoke elbow can and does move in the hub's spoke hole causing large peak loads that can quickly fatigue an already stressed and perhaps weakened part of the spoke.
A sufficiently tensioned wheel does not allow relative movement between the spoke head (elbow/J-bend) and the spoke hole and its spokes do not break.
Harley-Davidson uses J-bend spokes and has had more than a little trouble with their aluminum-hubed wheels breaking them. First, they were not tensioning the spokes enough to prevent load cycling movement and, secondly, the soft alloy hubs were deforming around the spoke holes such that the spokes were losing tension. They never had this problem with their old steel hubs.
On the other hand, I have never, ever seen a BMW with loose spokes, never had to true one and I have been working on them for more than fifty years. All BMW wheels use straight spokes with no bends (we used to call them 'nail-head' spokes). All BMW wheels use aluminum hubs and rims. All of them have (or had) a small steel reinforcing plate between the spoke head and hub. They are the most reliable motorcycle wheels I know of.
I do not believe that my 16/20-spoked wheels would carry my fat (230#) ass around if they were made with J-bend spokes. In any case, I have no intention of personally discovering the truth of the matter. If I wish to add flex to my wheels, I'll do it with spoke diameter selection and cross pattern, not wiggling the J-bend in a hub's spoke hole. Straight spokes are superior to those with bent ends in a couple of ways, but, are not versatile. Straight spokes cannot be mixed and matched between hubs & rims; the hubs, rims and spokes must be machined to fit together.
Joe
Oh Yeah, regarding Jobst: He got most things right but not all. I can't understand how he thinks gyroscopic forces have little more than a minor roll in bicycle stability. He was occasionally bone-headed.
Last edited by Joe Minton; 05-02-15 at 10:20 PM.
#69
Junior Member
Thread Starter
Join Date: Apr 2013
Location: McKinney, TX
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thanks for the comments on the Laser spokes. To be honest I didnt even pay attention to the spoke sizing when I ordered. Saw CX Ray made from Laser and I grabbed the Laser.
I stepped up to the Sapim Force spokes. 2.18-1.8-2.0 butting. They will an advantage over the lasers in deformation for a given load (~30% less deformation), and according to Sapim (?) data fatigue life second to the CX-Ray. Image below is sourced from the FLO site.
If the data im finding randomly is correct, the fatigue test is ~400 lb load at 10 hz for a single spoke. My Garmin says my wheel circumference is 2124mm, or ~6.9 ft. 30 mph = 44 feet/sec, so 6.4 Hz for comparison.
I want these wheels to be pretty stout, the Laser would probably be fine, but I stepped up a bit.
[TABLE="width: 100%"]
[TR]
[TD]Type[/TD]
[TD="width: 154"]Weight (x64@260mm)[/TD]
[TD="width: 154"]Strength[/TD]
[TD="width: 154"]Fatique life (revolutions)[/TD]
[/TR]
[TR]
[TD="width: 154"]Zinc[/TD]
[TD="width: 154"]424g[/TD]
[TD="width: 154"]950-1050n/mm2[/TD]
[TD="width: 154"]700,000[/TD]
[/TR]
[TR]
[TD="width: 154"]Leader[/TD]
[TD="width: 154"]421g[/TD]
[TD="width: 154"]1080-1180n/mm2[/TD]
[TD="width: 154"]870,000[/TD]
[/TR]
[TR]
[TD="width: 154"]Strong[/TD]
[TD="width: 154"]430g[/TD]
[TD="width: 154"]1400n/mm2[/TD]
[TD="width: 154"]1.6 million[/TD]
[/TR]
[TR]
[TD="width: 154"]Force[/TD]
[TD="width: 154"]368g[/TD]
[TD="width: 154"]1350n/mm2[/TD]
[TD="width: 154"]2 million[/TD]
[/TR]
[TR]
[TD="width: 154"]Race[/TD]
[TD="width: 154"]360g[/TD]
[TD="width: 154"]1350n/mm2[/TD]
[TD="width: 154"]980,000[/TD]
[/TR]
[TR]
[TD="width: 154"]D-Light[/TD]
[TD="width: 154"]309g[/TD]
[TD="width: 154"]1300n/mm2[/TD]
[TD="width: 154"][/TD]
[/TR]
[TR]
[TD="width: 154"]Laser[/TD]
[TD="width: 154"]279g[/TD]
[TD="width: 154"]1500n/mm2[/TD]
[TD="width: 154"]1.25 million[/TD]
[/TR]
[TR]
[TD="width: 154"]CX[/TD]
[TD="width: 154"]423g[/TD]
[TD="width: 154"]1200n/mm2[/TD]
[TD="width: 154"]To be announced[/TD]
[/TR]
[TR]
[TD="width: 154"]CX-Ray[/TD]
[TD="width: 154"]272g[/TD]
[TD="width: 154"]1600n/mm2[/TD]
[TD="width: 154"]3.5 million[/TD]
[/TR]
[TR]
[TD="width: 154"]Super spoke[/TD]
[TD="width: 154"]231g[/TD]
[TD="width: 154"]To be announced[/TD]
[TD="width: 154"]To be announced[/TD]
[/TR]
[TR]
[TD="width: 154"]CX Super[/TD]
[TD="width: 154"]To be announced[/TD]
[TD="width: 154"]To be announced[/TD]
[TD="width: 154"]To be announced[/TD]
[/TR]
[/TABLE]
I stepped up to the Sapim Force spokes. 2.18-1.8-2.0 butting. They will an advantage over the lasers in deformation for a given load (~30% less deformation), and according to Sapim (?) data fatigue life second to the CX-Ray. Image below is sourced from the FLO site.
If the data im finding randomly is correct, the fatigue test is ~400 lb load at 10 hz for a single spoke. My Garmin says my wheel circumference is 2124mm, or ~6.9 ft. 30 mph = 44 feet/sec, so 6.4 Hz for comparison.
I want these wheels to be pretty stout, the Laser would probably be fine, but I stepped up a bit.
[TABLE="width: 100%"]
[TR]
[TD]Type[/TD]
[TD="width: 154"]Weight (x64@260mm)[/TD]
[TD="width: 154"]Strength[/TD]
[TD="width: 154"]Fatique life (revolutions)[/TD]
[/TR]
[TR]
[TD="width: 154"]Zinc[/TD]
[TD="width: 154"]424g[/TD]
[TD="width: 154"]950-1050n/mm2[/TD]
[TD="width: 154"]700,000[/TD]
[/TR]
[TR]
[TD="width: 154"]Leader[/TD]
[TD="width: 154"]421g[/TD]
[TD="width: 154"]1080-1180n/mm2[/TD]
[TD="width: 154"]870,000[/TD]
[/TR]
[TR]
[TD="width: 154"]Strong[/TD]
[TD="width: 154"]430g[/TD]
[TD="width: 154"]1400n/mm2[/TD]
[TD="width: 154"]1.6 million[/TD]
[/TR]
[TR]
[TD="width: 154"]Force[/TD]
[TD="width: 154"]368g[/TD]
[TD="width: 154"]1350n/mm2[/TD]
[TD="width: 154"]2 million[/TD]
[/TR]
[TR]
[TD="width: 154"]Race[/TD]
[TD="width: 154"]360g[/TD]
[TD="width: 154"]1350n/mm2[/TD]
[TD="width: 154"]980,000[/TD]
[/TR]
[TR]
[TD="width: 154"]D-Light[/TD]
[TD="width: 154"]309g[/TD]
[TD="width: 154"]1300n/mm2[/TD]
[TD="width: 154"][/TD]
[/TR]
[TR]
[TD="width: 154"]Laser[/TD]
[TD="width: 154"]279g[/TD]
[TD="width: 154"]1500n/mm2[/TD]
[TD="width: 154"]1.25 million[/TD]
[/TR]
[TR]
[TD="width: 154"]CX[/TD]
[TD="width: 154"]423g[/TD]
[TD="width: 154"]1200n/mm2[/TD]
[TD="width: 154"]To be announced[/TD]
[/TR]
[TR]
[TD="width: 154"]CX-Ray[/TD]
[TD="width: 154"]272g[/TD]
[TD="width: 154"]1600n/mm2[/TD]
[TD="width: 154"]3.5 million[/TD]
[/TR]
[TR]
[TD="width: 154"]Super spoke[/TD]
[TD="width: 154"]231g[/TD]
[TD="width: 154"]To be announced[/TD]
[TD="width: 154"]To be announced[/TD]
[/TR]
[TR]
[TD="width: 154"]CX Super[/TD]
[TD="width: 154"]To be announced[/TD]
[TD="width: 154"]To be announced[/TD]
[TD="width: 154"]To be announced[/TD]
[/TR]
[/TABLE]
Last edited by kafreeman; 05-05-15 at 04:00 PM.
#70
Senior Member
Interesting data.
I know I was recently reading the November Wheels website and noticed they don't seem to give much credence to CX-Ray vs Laser (at least not in performance) and so choose to push Lasers almost exclusively.
(shrug)
I know I was recently reading the November Wheels website and noticed they don't seem to give much credence to CX-Ray vs Laser (at least not in performance) and so choose to push Lasers almost exclusively.
(shrug)
#71
Redefining Lazy
Join Date: Apr 2008
Location: North Metro, MN
Posts: 1,923
Bikes: 2013 Cannondale Synapse 5 105, 2013 Giant Escape 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
230# + bike = 260# ready to ride. My wheel set is a Shimano RS10 with 16/20 spokes.
4K or so miles with no problems. None. However, I've never hit a pothole, jumped a curb or anything like that. The roads around here are smooth. If I were to consider another set of wheels it would be the Shimano Ultegra 6800s because they are lighter. I have enormous respect for Shimano's engineering and construction quality; their wheels are superb.
4K or so miles with no problems. None. However, I've never hit a pothole, jumped a curb or anything like that. The roads around here are smooth. If I were to consider another set of wheels it would be the Shimano Ultegra 6800s because they are lighter. I have enormous respect for Shimano's engineering and construction quality; their wheels are superb.
I'm (unfortunately) 230# and have almost 5000 miles on mine and they are straight as a pin.
Great wheels, for stock.
S
#72
Senior Member
The uncooked pasta is obviously stiffer than the paper. However, it's not more resistant to permanent deflections. If you flex the pasta past a certain point it's not going to return. It breaks. However the paper will not break like the pasta.
----
Stiffness refers to the elastic deformation of something. If something is stiff, it resists elastic deformation. The pasta is stiff. It takes considerably more effort to flex the pasta at all versus the paper. Hell, I'd bet that a breeze could flex a piece of paper that has the same dimensions of a piece of angle hair.
Strength refers to resistance to permanent deformation. The paper will be stronger than the pasta. You can apply a lot more force to the paper than the pasta without the paper suddenly snapping in half.
----
Originally Posted by Mr IGH
This statement doesn't have any foundation in engineering
I assume you must be referring to your own post, correct?
Last edited by Deontologist; 05-05-15 at 11:02 PM.
#74
Senior Member
Join Date: Oct 2010
Posts: 182
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 26 Times
in
10 Posts
You have to consider that a spoke doesn't cycle load on every revolution. A properly spec'd and built wheel should have spokes that cycle load (go slack and then return to tension) only on very rare occasions. The cycles to failure shown in the chart represent about 60 hours of riding assuming a cycle on every wheel revolution. If the chart represented mean time to failure or anything like it, the wheels I'm currently using (which have Laser spokes) should have failed by now if I'd started using them sometime around St. Patrick's Day. Instead they are in brand new condition.
An illustration I've often done is to line up a Race, Laser, and CX Ray spoke, each standing up. I ask a person to push straight down on each until the spoke bends in the middle. What happens is they say "ouch" with the Race and it doesn't bend, they say "ouch" with the Laser but it does bend, and the CX Ray bends. Each spoke has the same properties at the ends, but the Laser and CX Ray's willingness to bend in the middle absorbs that cycle load and protects the end of the spoke, which is where spokes break from cycle fatigue. The other spokes that perform well in cycle fatigue on that chart have more metal at the spoke end, and also weigh significantly more, than a Laser or CX Ray. But if the wheel builder does his/her job correctly, and the wheel isn't ridden beyond what it's spec'd for, cycle fatigue is likely to come into play only after the rim is toast, the bike is replaced, 13 speed cassettes come out, or some other such thing.
We also maintain a belief that spokes are an efficient way to make a wheel strong. You can use heavier rims and spokes with more mass and make a low spoke wheel that's strong enough for heavy guys, totally. You can buy a wheel with 3 spokes that will hold up GREAT for heavy guys. We'd just prefer to build someone like the OP a 28/32 set (or perhaps 24/28) that weighs the better part of a pound less than the wheels that Joe M advocates, has some built in redundancy in terms of if a spoke should happen to break, has quite good aerodynamics, and uses parts that are and will be readily available into the foreseeable future. We've built a ton of them and we know they last a long long time and make for happy riders. Our approach isn't what everyone wants, though. We respect that and are totally fine with it.
Last edited by November Dave; 05-06-15 at 03:23 AM. Reason: man am i long winded, sorry
#75
Thread Killer
Join Date: Aug 2008
Location: Ann Arbor, MI
Posts: 12,373
Bikes: 15 Kinesis Racelight 4S, 76 Motebecane Gran Jubilée, 17 Dedacciai Gladiatore2, 12 Breezer Venturi, 09 Dahon Mariner, 12 Mercier Nano, 95 DeKerf Team SL, 19 Tern Rally, 21 Breezer Doppler Cafe+, 19 T-Lab X3, 91 Serotta CII
Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 3078 Post(s)
Liked 1,631 Times
in
1,005 Posts
@November Dave have you looked at the CX? It seems like a top choice for a clyde wheel, especially a 28h rear, given the extra width and thickness over the CX-Ray while retaining the forged aero shaping characteristics.
I don't think the CX is new-- I don't follow the spoke world closely-- but it sure is overlooked, playing in the shadow of the CX-Ray, but while offering advantages for bigger, stronger riders.
What are your thoughts on the CX?
I don't think the CX is new-- I don't follow the spoke world closely-- but it sure is overlooked, playing in the shadow of the CX-Ray, but while offering advantages for bigger, stronger riders.
What are your thoughts on the CX?