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  1. #26
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    Quote Originally Posted by Fredrico View Post
    Well, Mavic has gotten some disrespect in the cycling community as having problems with quality control. Open Pros were a great example.
    At this point, I would avoid anything with the name Mavic on it with the exception of the A719 touring rims. Those are quite good at what they are designed for.

    Quote Originally Posted by Fredrico View Post
    Yep, those paired spoked rims concentrated too much force on the rims at the spoke holes. Spoking alternating from left and right, spreads the stress out more along the entire rim, so would take much longer to develop cracks. Have to wonder why they went with paired spokes in the first place. They thought it made a stiffer wheel.........
    No. I think Trek's only motive for this design is that they thought it looked "sexy" and would lure more buyers. As we all know, sex sells. It definitely does not make for a stiffer wheel. The best way to get a stiffer wheel is MORE SPOKES.

    Quote Originally Posted by Fredrico View Post
    I'll stick with brass eyelets, regardless that some rims wouldn't need them. How ya gonna tell which ones are strong enough and which aren't?
    I think when riders are trashing the brake tracks before spoke holes crack or spokes break, that is a good sign that eyelets or washers added to those wheels would not have helped in the longevity of the wheel. I have yet to hear of a HED Belgium or H+ Son Archetype cracking. Of course that doesn't mean it isn't impossible if the rider weighs 300lbs. and tries hard enough. But if the rider is 300lbs. and riding a road bike with road wheels, I think he will have more problems with his bike besides cracked spoke holes.

    And some riders say eyelets make an annoying rattle. Personally, I have not noticed the noise. I had a set of Weinmann Zac19 rims on a hybrid awhile back. The alloy must be really soft because at 6,000 miles, the brake tracks were scored to the point I got some annoying pulsating while braking. Though I never noticed the eyelet rattle people complain about.

    You know the old saying about the chain only being as good as the weakest link. It doesn't do any good to overbuild one aspect of a product at the expense of others.
    Last edited by Lombard; 02-14-2019 at 06:57 AM.
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  2. #27
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    Quote Originally Posted by Fredrico View Post

    Yep, those paired spoked rims concentrated too much force on the rims at the spoke holes. Spoking alternating from left and right, spreads the stress out more along the entire rim, so would take much longer to develop cracks. Have to wonder why they went with paired spokes in the first place. They thought it made a stiffer wheel, I guess, which would be BS. Nothing stiffer than a well tensioned 32 spoke wheel.
    I have a friend that uses Rolf wheels, which have paired spokes. He rode RAM so he rides many many miles. He says that the Rolf wheels he had were the most durable wheels he's ever used. I don't think paired spokes are responsible for cracking rims any more than regular spoking patterns. Bontrager wheels are just not durable. I've seen and had them crack, paired spokes or not.

  3. #28
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    Quote Originally Posted by mfdemicco View Post
    I have a friend that uses Rolf wheels, which have paired spokes. He rode RAM so he rides many many miles. He says that the Rolf wheels he had were the most durable wheels he's ever used. I don't think paired spokes are responsible for cracking rims any more than regular spoking patterns. Bontrager wheels are just not durable. I've seen and had them crack, paired spokes or not.
    I belive Campy makes some paired spoke wheels as well and they don't have problems either.

    That being said, just because a design doesn't have a problem doesn't mean there is a reason for this design other than aesthetics. Logic and common sense would point to spreading spokes evenly around the wheel as the best design. If you design a wheel otherwise, you will need to compensate for it somewhere else such as making the rim bed thicker and stronger. The same applies to low spoke count wheels.
    "With bicycles in particular, you need to separate between what's merely true and what's important."-- DCGriz, RBR.

    “Statistics are like bikinis. What they reveal is suggestive, but what they conceal is vital.” -- Aaron Levenstein



  4. #29
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    Velocity A23 rim crack

    Quote Originally Posted by Lombard View Post
    I belive Campy makes some paired spoke wheels as well and they don't have problems either.

    That being said, just because a design doesn't have a problem doesn't mean there is a reason for this design other than aesthetics. Logic and common sense would point to spreading spokes evenly around the wheel as the best design. If you design a wheel otherwise, you will need to compensate for it somewhere else such as making the rim bed thicker and stronger. The same applies to low spoke count wheels.
    Yes, there seems to be no advantage and rims have to be stiffer (heavier) to keep the rim from becoming lobed shaped because of the large distance between spokes.
    Last edited by mfdemicco; 02-14-2019 at 03:19 PM.

  5. #30
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    Quote Originally Posted by Fredrico View Post
    Nothing stiffer than a well tensioned 32 spoke wheel.

    how about a well tensioned 36 spoke wheel? Back in the day it was the standard, and the rims were lighter. Just saying.

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    If we're talking about 32 or 36h wheel with box section rims, it's easy to surpass their stiffness with almost any modern build. A modern deeper section rim with 32h lacing is going to build into an exceptionally stiff wheel, with almost no lateral rim movement under torque.

    In my experience, cracking spoke holes are the rim's fault, not the spoke tension's fault. I'd not suggest trying this at home, but lay a wheel, hub end cap down, on the ground and jump on the spokes. Some rims take this all day long and laugh (or the spokes snap). Some rims will crack at the spoke hole every time you do this. Some rims exhibit both behaviors randomly in different experiments. I've done this to a bunch of wheels.

  7. #32
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    Quote Originally Posted by Kerry Irons View Post
    how about a well tensioned 36 spoke wheel? Back in the day it was the standard, and the rims were lighter. Just saying.
    Well yes, of course. I believe Fred was referring to today's world of insanely low spoke count road wheels.

    But you do bring up a point. We know that more spokes make for a stiffer wheel. At what point is it a case of diminishing returns?
    "With bicycles in particular, you need to separate between what's merely true and what's important."-- DCGriz, RBR.

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  8. #33
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    Quote Originally Posted by Lombard View Post
    Well yes, of course. I believe Fred was referring to today's world of insanely low spoke count road wheels.

    But you do bring up a point. We know that more spokes make for a stiffer wheel. At what point is it a case of diminishing returns?
    Around 40 spokes? . Back in the box section rim days, touring bikes had 40 spoked rear wheels.

    According to long time convention, Bernard Hinault mentioned it in his book, 32 spokes are all a racer needs for a bulletproof set of very stiff wheels. They're still ubiquitous in the TDF. I went with 36 spokes on both bikes and never regretted it.

    The brass eyelet box rims I've used, Wolber Super Champion, Ambrosio Elite Durex, and Campy Lambda, have lasted 20K, 30K miles. I've been holding a replacement rim for the Wolber rear wheel, the oldest of the lot, for about 5 years, as the brake surfaces are becoming concave and will split sooner or later. So far, so good. I bought that wheel back in '83. It has 80K miles on it, easily, serving on two bikes.

    32 and 36 spoked rims will always be available, so it's a simple matter to replace the rims on the same hubs. We could do it at the shop in 40 minutes. Hubs will last forever if cleaned and greased every 10K miles. I've even used the same DT stainless steel 14 ga. spokes if they don't look scored at the bends, and never had a spoke break. Even tension around the wheel is the key.

    Kerry is right on, 36 spoked wheels are the stiffest wheels around. I'll test these wheels against any lower spoke count wheels, although appreciate that thick aero rims are no doubt "stiffer" than aluminum box section rims. So what? 32 or 36 spokes take care of holding the wheel true just fine, instead of a massive rim supported by considerably fewer spokes. Box section on 36 spokes also have more material spread out to dissipate shocks and are nice and comfortable, IME.

    Never had a problem with brake pads rubbing on rims when climbing after I figured out how to properly tension the spokes.

  9. #34
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    Quote Originally Posted by November Dave View Post
    I'd not suggest trying this at home, but lay a wheel, hub end cap down, on the ground and jump on the spokes. Some rims take this all day long and laugh (or the spokes snap). Some rims will crack at the spoke hole every time you do this.
    Yep.

    Well, maybe not jumping on the wheel, but pressing vigorously around the rim with it sitting firmly on the floor, the twisted spokes from the wrenching may crack once as they seat, but that should be it. If it keeps cracking, a spoke is probably too loose or the rim is really weak, possibly split at a spoke hole, as you suggest. I've seen it a few times. Even cheap box section rims stop cracking after touch up truing and tensioning following the first "pressing." The second go around should not pull the wheel out of true. Amazing how that works.

  10. #35
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    Quote Originally Posted by Fredrico View Post
    Around 40 spokes? . Back in the box section rim days, touring bikes had 40 spoked rear wheels.

    According to long time convention, Bernard Hinault mentioned it in his book, 32 spokes are all a racer needs for a bulletproof set of very stiff wheels. They're still ubiquitous in the TDF. I went with 36 spokes on both bikes and never regretted it.

    The brass eyelet box rims I've used, Wolber Super Champion, Ambrosio Elite Durex, and Campy Lambda, have lasted 20K, 30K miles. I've been holding a replacement rim for the Wolber rear wheel, the oldest of the lot, for about 5 years, as the brake surfaces are becoming concave and will split sooner or later. So far, so good. I bought that wheel back in '83. It has 80K miles on it, easily, serving on two bikes.

    32 and 36 spoked rims will always be available, so it's a simple matter to replace the rims on the same hubs. We could do it at the shop in 40 minutes. Hubs will last forever if cleaned and greased every 10K miles. I've even used the same DT stainless steel 14 ga. spokes if they don't look scored at the bends, and never had a spoke break. Even tension around the wheel is the key.

    Kerry is right on, 36 spoked wheels are the stiffest wheels around. I'll test these wheels against any lower spoke count wheels, although appreciate that thick aero rims are no doubt "stiffer" than aluminum box section rims. So what? 32 or 36 spokes take care of holding the wheel true just fine, instead of a massive rim supported by considerably fewer spokes. Box section on 36 spokes also have more material spread out to dissipate shocks and are nice and comfortable, IME.

    Never had a problem with brake pads rubbing on rims when climbing after I figured out how to properly tension the spokes.
    Everything you said here is pretty much true except the part about thick aero rims being stiffer and less comfortable. Here is a good article every wheel builder should read:

    https://www.slowtwitch.com/Tech/Debu...ness_3449.html
    "With bicycles in particular, you need to separate between what's merely true and what's important."-- DCGriz, RBR.

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  11. #36
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    Quote Originally Posted by Lombard View Post
    We know that more spokes make for a stiffer wheel. At what point is it a case of diminishing returns?
    No we don't. Stiffer wheels make stiffer wheels and number of spoke is just one of very many things that contribute, or detract, from that.

  12. #37
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    Quote Originally Posted by Jay Strongbow View Post
    No we don't. Stiffer wheels make stiffer wheels and number of spoke is just one of very many things that contribute, or detract, from that.
    You may want to read the Slowtwitch article I linked in post 35 before you dismiss my statement.
    "With bicycles in particular, you need to separate between what's merely true and what's important."-- DCGriz, RBR.

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  13. #38
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    Quote Originally Posted by Lombard View Post
    You may want to read the Slowtwitch article I linked in post 35 before you dismiss my statement.
    ha, that's a good one.

    Actually you might want to read it. The whole point is that there are a lot of things that contribute to a wheel's stiffness.

  14. #39
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    Quote Originally Posted by Jay Strongbow View Post
    ha, that's a good one.

    Actually you might want to read it. The whole point is that there are a lot of things that contribute to a wheel's stiffness.
    And how does this dismiss what I originally said? More than one thing, yes. "A lot" is a stretch, dontcha think?

    My point in my reply to Fred is that deep section rims are not less comfortable than box rims. Contrary to what many riders may think, wheels have a negligible effect on comfort. "Stiffness" as in the ability to resist lateral movement is a different story. Here again, rim design has little to no effect on this.
    "With bicycles in particular, you need to separate between what's merely true and what's important."-- DCGriz, RBR.

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    Quote Originally Posted by Jay Strongbow View Post
    ha, that's a good one.

    Actually you might want to read it. The whole point is that there are a lot of things that contribute to a wheel's stiffness.
    And Jobst Brandt said in the book "The Bicycle Wheel" that wheels are stiff enough, so why do we care if 36 spokes make stiffer wheels than 32?

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    Quote Originally Posted by Lombard View Post
    And how does this dismiss what I originally said? More than one thing, yes. "A lot" is a stretch, dontcha think?

    My point in my reply to Fred is that deep section rims are not less comfortable than box rims. Contrary to what many riders may think, wheels have a negligible effect on comfort. "Stiffness" as in the ability to resist lateral movement is a different story. Here again, rim design has little to no effect on this.
    Did you even read the article you linked to?

    You can decide for yourself why it's very easy to meet or exceed the lateral stiffness of old school 32-36 spoke wheels with modern components and many less spokes. Or choose not be believe it if you'd like.

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    Quote Originally Posted by mfdemicco View Post
    And Jobst Brandt said in the book "The Bicycle Wheel" that wheels are stiff enough, so why do we care if 36 spokes make stiffer wheels than 32?
    Right.
    Not like I scientifically measured it but I've had a lot of wheels and the stiffest by far seemed to be 24/20 spokes. The guy who build them said they would be really stiff and that was due to the dimensions of Alchemy hubs. The most laterally flexy where 32/32 with Mavic Open pro rims. No mystery why those were the least stiff (except for Lombard) but they were plenty stiff enough for my 145 pounds.

    I'm a big fan of spoke overkill but that's only because I'm less screwed if I break one on the road. With regard to lateral stiffness there's not need for a ton of spokes in this day and age as long as you choose the right components.

  18. #43
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    Quote Originally Posted by Lombard View Post
    Everything you said here is pretty much true except the part about thick aero rims being stiffer and less comfortable. Here is a good article every wheel builder should read:

    https://www.slowtwitch.com/Tech/Debu...ness_3449.html
    This rang true, IME:

    How often do riders complain of their shallow-section aluminum wheels not being stiff enough? I don’t know about you, but I almost never hear that – short of a wheel with spokes that are far too loose. The reason you never hear that is because most aluminum wheels have relatively high spoke stiffness and relatively low rim stiffness. Think of wheel with 32 spokes of 2mm diameter, laced to a 20mm deep alloy rim – that’s a lot of spoke material and not much rim.

    An astoundingly stiff, deep-section carbon rim – strapped on to a handful of thin aero spokes. The stiff rim can literally overpower the spokes. If your rim rubs your rear brake pads, this is probably why.

    Case closed!

  19. #44
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    Quote Originally Posted by Fredrico View Post
    This rang true, IME:

    How often do riders complain of their shallow-section aluminum wheels not being stiff enough? I don’t know about you, but I almost never hear that – short of a wheel with spokes that are far too loose. The reason you never hear that is because most aluminum wheels have relatively high spoke stiffness and relatively low rim stiffness. Think of wheel with 32 spokes of 2mm diameter, laced to a 20mm deep alloy rim – that’s a lot of spoke material and not much rim.

    An astoundingly stiff, deep-section carbon rim – strapped on to a handful of thin aero spokes. The stiff rim can literally overpower the spokes. If your rim rubs your rear brake pads, this is probably why.

    Case closed!
    You and I read this part, Fred. Apparently Jay didn't read these paragraphs and decided to shoot from the hip.
    Last edited by Lombard; 02-16-2019 at 02:52 PM.
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  20. #45
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    Quote Originally Posted by Lombard View Post
    You and I read this part, Fred. Apparently Jay didn't read these paragraphs and decided to shoot from the hip.
    As for the equivalent of being told by Trump I have a bad haircut. That's funny.
    As for what you quoted from the article. Yes, we all know apples are different from oranges. There is more to the example than more spokes.

    "Nothing stiffer than a well tensioned 32 spoke wheel."
    "We know that more spokes make for a stiffer wheel."

    Those are the statements that are incomplete at best.

    Some other things that make for a stiff, or not:
    -Rim Material
    -Rim geometry
    -hub geometry
    -Spoke material
    -Spoke guage
    -Spoke pattern
    -Spoke tension (very minor)
    -Bracing angles (though that's just just the product of rim and hub geometry)
    -Dish (rear only of course).

    A 'wheel', all of it, is what makes a wheel stiff or not. Not even close to just spoke count.

    And there is absolutely no question a 24 spoke wheel (just to use a random example) with all those things being favorable can be made stiffer and stronger then a 32 spoke wheel with them not being favorable.

    Poser and weight-weenie-ism are not the only reasons we see lower spoke counts than decades past. It's because modern wheel components can achieve the same or more stiffness and strength with less spokes.

  21. #46
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    Quote Originally Posted by Jay Strongbow View Post
    As for the equivalent of being told by Trump I have a bad haircut. That's funny.
    As for what you quoted from the article. Yes, we all know apples are different from oranges. There is more to the example than more spokes.

    "Nothing stiffer than a well tensioned 32 spoke wheel."
    "We know that more spokes make for a stiffer wheel."

    Those are the statements that are incomplete at best.

    Some other things that make for a stiff, or not:
    -Rim Material
    -Rim geometry
    -hub geometry
    -Spoke material
    -Spoke guage
    -Spoke pattern
    -Spoke tension (very minor)
    -Bracing angles (though that's just just the product of rim and hub geometry)
    -Dish (rear only of course).

    A 'wheel', all of it, is what makes a wheel stiff or not. Not even close to just spoke count.

    And there is absolutely no question a 24 spoke wheel (just to use a random example) with all those things being favorable can be made stiffer and stronger then a 32 spoke wheel with them not being favorable.

    Poser and weight-weenie-ism are not the only reasons we see lower spoke counts than decades past. It's because modern wheel components can achieve the same or more stiffness and strength with less spokes.
    Is this what you got out of that article, Jay? Yes, it is true that these items mentioned play a part as stated in the article "total stiffness of the system":

    -Axle diameter and thickness
    -Spoke count
    -Number of spoke crossings
    -Spoke thickness
    -Spoke material
    -Spoke type (j-bend or straight pull)
    -Rim depth
    -Rim width
    -Rim material
    -Fork leg stiffness and steerer tube diameter
    -Chainstay and seatstay design
    -Dropout alignment

    On trying to make a wheel "stiffer" by raising hub flanges:

    Please let me insert a screeching halt. Screeeeeeeech!

    This is ONLY true if we’re talking about consistent flange spacing between the two different hubs. If your hub flanges are very tall – but not placed very wide, the resulting spoke angle is often worse than short, wide flanges. High flanges also carry a weight penalty – so they must be balanced with the total performance intent of the wheel.

    The obvious limiting factor on rear wheel flange spacing is the cassette; this takes up a substantial amount of space on the drive side, and is a key limiter in rear wheel lateral stiffness. This is also the reason we often see flanges of unequal height on rear wheels (higher on the drive side) – some manufacturers are scraping for every last bit of spoke angle they can get.

    Now, can we agree that there is only so much you can do with hub geometry due to space necessary for an 11-speed freehub? So while you may eek out a bit better bracing angle, we're talking about a drop in a bucket. Not to mention that you open up other issues when you raise flanges.

    Now, on to the part about wider and deeper rims being stiffer. Yes, the RIMS are stiffer. But........

    When you start climbing or sprinting on a carbon wheel, the stiff rim tends to want to stay perfectly straight – relative to itself.

    This gets compounded by the fact that most “race” wheels have thin aerodynamic spokes – AND not very many of them. On top of that, in very recent years, we have also seen carbon rims grow in both width and depth – subsequently gaining both lateral and radial stiffness.

    What this adds up to is the perfect wheel storm: An astoundingly stiff, deep-section carbon rim – strapped on to a handful of thin aero spokes. The stiff rim can literally overpower the spokes. If your rim rubs your rear brake pads, this is probably why.

    So paradoxically (in case you didn't get this from the article), a stiffer rim can make for a wheel which is LESS stiff. So in theory, if you want the stiffest wheel possible, you want the shallowest, narrowest rim. Of course this isn't practical for other reasons.

    So at the end of the day, the most practical way to make a wheel stiffer (as in being least likely to flex enough to rub brakes or frame) is by adding spokes and using thicker spokes.


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  22. #47
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    Quote Originally Posted by Lombard View Post
    Is this what you got out of that article, Jay? Yes, it is true that these items mentioned play a part as stated in the article "total stiffness of the system":

    -Axle diameter and thickness
    -Spoke count
    -Number of spoke crossings
    -Spoke thickness
    -Spoke material
    -Spoke type (j-bend or straight pull)
    -Rim depth
    -Rim width
    -Rim material
    -Fork leg stiffness and steerer tube diameter
    -Chainstay and seatstay design
    -Dropout alignment

    On trying to make a wheel "stiffer" by raising hub flanges:

    Please let me insert a screeching halt. Screeeeeeeech!

    This is ONLY true if we’re talking about consistent flange spacing between the two different hubs. If your hub flanges are very tall – but not placed very wide, the resulting spoke angle is often worse than short, wide flanges. High flanges also carry a weight penalty – so they must be balanced with the total performance intent of the wheel.

    The obvious limiting factor on rear wheel flange spacing is the cassette; this takes up a substantial amount of space on the drive side, and is a key limiter in rear wheel lateral stiffness. This is also the reason we often see flanges of unequal height on rear wheels (higher on the drive side) – some manufacturers are scraping for every last bit of spoke angle they can get.

    Now, can we agree that there is only so much you can do with hub geometry due to space necessary for an 11-speed freehub? So while you may eek out a bit better bracing angle, we're talking about a drop in a bucket. Not to mention that you open up other issues when you raise flanges.

    Now, on to the part about wider and deeper rims being stiffer. Yes, the RIMS are stiffer. But........

    When you start climbing or sprinting on a carbon wheel, the stiff rim tends to want to stay perfectly straight – relative to itself.

    This gets compounded by the fact that most “race” wheels have thin aerodynamic spokes – AND not very many of them. On top of that, in very recent years, we have also seen carbon rims grow in both width and depth – subsequently gaining both lateral and radial stiffness.

    What this adds up to is the perfect wheel storm: An astoundingly stiff, deep-section carbon rim – strapped on to a handful of thin aero spokes. The stiff rim can literally overpower the spokes. If your rim rubs your rear brake pads, this is probably why.

    So paradoxically (in case you didn't get this from the article), a stiffer rim can make for a wheel which is LESS stiff. So in theory, if you want the stiffest wheel possible, you want the shallowest, narrowest rim. Of course this isn't practical for other reasons.

    So at the end of the day, the most practical way to make a wheel stiffer (as in being least likely to flex enough to rub brakes or frame) is by adding spokes and using thicker spokes.


    You said it well!

    It may be true short spokes possible on a fat aero rim can be very efficient linkage between rim and hub, but they're the weak link in the system and are more likely to fail than 32 or 36 spokes crossed three or sometimes four.

    That's exactly why I've had great luck with cheap, replaceable box section 19mm or 20mm wide shallow rims. They stand up to out of saddle sprints and hard climbing without protest and absorb shocks nicely. The rim comes from the factory true "relative to itself," but the 36 properly tensioned spokes hold the wheel true on a ride, not the rim itself! There are so many spokes, none break, and if one does in an accident, the rim has a great chance to not pretzel into oblivion. Rider widens the brake blocks and makes it home.

  23. #48
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    Quote Originally Posted by Fredrico View Post
    You said it well!

    It may be true short spokes possible on a fat aero rim can be very efficient linkage between rim and hub, but they're the weak link in the system and are more likely to fail than 32 or 36 spokes crossed three or sometimes four.

    That's exactly why I've had great luck with cheap, replaceable box section 19mm or 20mm wide shallow rims. They stand up to out of saddle sprints and hard climbing without protest and absorb shocks nicely.
    Stop right there. Rims do not perceivably absorb shocks, tires do.
    "With bicycles in particular, you need to separate between what's merely true and what's important."-- DCGriz, RBR.

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  24. #49
    'brifter' is a lame word.
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    Quote Originally Posted by karlg View Post
    A little online searching definitely agrees with your experience. I had hoped that a hand-built 32 spoke wheel would hold up better.
    Quote Originally Posted by Kerry Irons View Post
    When did this problem start? I have 40K miles on a set of A23s (OC rear rim) with no issues (example of one). Spoke hole cracks are indicative of too high tension for the rim. It may be a weak rim or a too-high tension build. Impossible to tell based on a photo rather than spoke tension information.
    Quote Originally Posted by Lombard View Post
    Stop right there. Rims do not perceivably absorb shocks, tires do.
    Exactly. People that talk about 'ride quality' and wheels in the same sentence are confused.
    I work for some bike racers
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  25. #50
    RoadBikeReview Member
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    Quote Originally Posted by Lombard View Post
    Stop right there. Rims do not perceivably absorb shocks, tires do.
    Take a 50 mile ride on time trial disc wheels and tell me they're just as comfortable as 32 spoke cross 3's. We all agreed in the listings above materials make a huge difference. 32 spoked box rims dissipate shocks more efficiently than a massive stiff rim on wimpy aero spokes. Try it.

    If all rider needs for comfort are tires, then why are builders tweaking the frame tubing and offering elastomer shocks, et. al? All materials on the bike either absorb shocks or pass them on. I thought we established that in the listings above.

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