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  1. #2576
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    Are the folks using the Rhythm rim strips using a 29 inch version? I clicked through to the Bontrager site, but they only show Rhythm version in 26 inch. The 29 inch version in stock are for RLX rims, which are narrower if my memory serves me?

  2. #2577
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    Quote Originally Posted by mashraf View Post
    totally agree with your view on this. my decision to not go with the LB wheels was solely based on the assumption that Enve / Reynolds wheels would have gone through a 'QC' process which is stricter than the LB wheels. The word to note is assumption and its ultimately down to a personal view/preference/cash!

    I cant wait to go out for a ride now, so taken half days leave on friday.
    Ya know, LB did publish their testing metrics, and I've yet to see Reynolds or Enve do the same. I'm just saying...how do you know it's "stricter"? Did you come to that conclusion based on their price tag, or did you see their testing metrics?

    Not being confrontational here...I'm genuinely curious.
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  3. #2578
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    Quote Originally Posted by Pau11y View Post
    Ya know, LB did publish their testing metrics, and I've yet to see Reynolds or Enve do the same. I'm just saying...how do you know it's "stricter"? Did you come to that conclusion based on their price tag, or did you see their testing metrics?

    Not being confrontational here...I'm genuinely curious.
    I think the assumption is based on the old saying "strong, light, cheap; pick two".

  4. #2579
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    InertiaMan Their stock is out of the 29er Rhythm about half the time. I think people from this thread have tripled demand lately.
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  5. #2580
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    Quote Originally Posted by Pau11y View Post
    Ya know, LB did publish their testing metrics
    Link?
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  6. #2581
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    Quote Originally Posted by meltingfeather View Post
    Link?
    Doh, my bad! I think it was DengFu bikes...I was looking for their 26er full squishy specs. Instead I came up on this page: download

    I distinctly recall a rim test report. Lemme go look at home, maybe I still have the download floating around. But like these, it was a jpg of their testing form.

    As for LB, they have this up: Spoke tension report for 650b rims - light-bicycle
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  7. #2582
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    Quote Originally Posted by Adroit Rider View Post
    I think the assumption is based on the old saying "strong, light, cheap; pick two".
    A saying coined by a guy who saw his business being undercut by copied asian made products that were, cheaper, as strong, and as light as his products.

    Light, cheap, strong, bling: pick three.

    There are loads of cheap, light and strong parts and frames out there.

  8. #2583
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    Quote Originally Posted by Pau11y View Post
    Doh, my bad! I think it was DengFu bikes...I was looking for their 26er full squishy specs. Instead I came up on this page: download

    I distinctly recall a rim test report. Lemme go look at home, maybe I still have the download floating around. But like these, it was a jpg of their testing form.

    As for LB, they have this up: Spoke tension report for 650b rims - light-bicycle
    That post contains just two data points showing what I would deem as in improper way to measure nipple pull out force and give maximum spoke tension guidelines.

    In this configuration you are going to have bending of the rim section as well as "nipple pull out" damage accumulation. The evidence of bending is in the nonlinear load vs. crosshead displacement curve. The evidence of damage accumultion is the crack pop-in event associated with the load drop at ~ 300 kgf.

    An appropriate test would be to fixture the rim section rigidly to the t-table near the spoke hole of interest and actually pull a nipple and threaded spoke through the hole with gripping on the spoke itself. If spoke elongation or nipple failure is a problem before rim failure then you've found the weakest link and the nipple holes are strong enough.

    Testing like this brings into question proper quality control metrics and data tracking/interpretation.

    These rims are now off the table for me.

    Thank you for the post Pauly.

  9. #2584
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    If anything though, the testing jig results in a harsher test. Mounting the jig closer to the spoke hole would result in less deformation of the rim and thus, probably a higher rated pull-out force.

    This type of testing might actually be preferable. Individual spokes can put a tensile load on the rim while the adjacent spokes remain more slack. This mimics the load put on a wheel when stressed laterally during a hard sideways landing. Drive side and non-drive-side spokes for lateral loads, leading vs trailing while braking and strikes to spokes from foreign objects, all result in a loads mimicked by the pictured light bicycle testing jig that holds the test rim near the two adjacent spoke holes.

    I do agree with your point that a more accurate test would be to pull on a spoke rather than pushing on something threaded through the outer side of the nipple. But as long as the spoke fully threads through the nipple head, which mine do, the tests are then identical. The discrepancy only matters when short spokes are used and not threaded all the way through the nipple head. Of course I'm assuming that nipples deform prior to any deformation of the threaded end of the spoke.

    If there is an issue to be had with that testing setup, it is that the spoke appears to be perpendicular to the rim. In real life, they come out at an angle. With that said though, it isn't possible to confirm this flaw from the provided photo. The exact angle being tested can't really be discerned from the photo.

    My guess is that the Light Bicycle engineers know what they're doing. Other than the nationality of the Light Bicycle, is there a reason to suspect that their design or testing process is less rigorous than at other companies?

  10. #2585
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    Quote Originally Posted by dfiler View Post
    My guess is that the Light Bicycle engineers know what they're doing. Other than the nationality of the Light Bicycle, is there a reason to suspect that their design or testing process is less rigorous than at other companies?
    Well, that's just what it is...a guess.
    I know for a fact that LB drills the spoke holes, and while you might say "so what", there is a significant difference in hoop strength (the strength around the spoke hole) compared to a molded hole (ENVE, and others). In a molded hole, the reinforcing fibers are distributed around the hole rather than being cut through by a drill bit . It's a much more difficult molding process when the holes are molded, and the mold cost is higher. This was the single factor that kept me from giving these rims a serious thought. Again, you get what you pay for.

  11. #2586
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    Quote Originally Posted by Simplemind View Post
    Well, that's just what it is...a guess.
    I know for a fact that LB drills the spoke holes, and while you might say "so what", there is a significant difference in hoop strength (the strength around the spoke hole) compared to a molded hole. In a molded hole, the reinforcing fibers are distributed around the hole rather than being cut through by a drill bit . It's a much more difficult molding process when the holes are molded, and the mold cost is higher. This was the single factor that kept me from giving these rims a serious thought. Again, you get what you pay for.

    So does Easton : Gallery: Easton Haven Carbon All-mountain Wheelset Launched - BikeRadar

  12. #2587
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    Quote Originally Posted by dfiler View Post
    My guess is that the Light Bicycle engineers know what they're doing. Other than the nationality of the Light Bicycle, is there a reason to suspect that their design or testing process is less rigorous than at other companies?
    The reasoning to suspect their design and testing procedures was provided by LB; the evidence as to how they determine their maximum spoke tension in a brittle material was the only deciding factor.

  13. #2588
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    Quote Originally Posted by newportl View Post
    Yep, at least they did in 2010, in Tijuana. I think the Easton wheels, except for their hubs, have a pretty good reputation.

  14. #2589
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    Quote Originally Posted by Simplemind View Post
    Well, that's just what it is...a guess.
    I know for a fact that LB drills the spoke holes, and while you might say "so what", there is a significant difference in hoop strength (the strength around the spoke hole) compared to a molded hole (ENVE, and others). In a molded hole, the reinforcing fibers are distributed around the hole rather than being cut through by a drill bit . It's a much more difficult molding process when the holes are molded, and the mold cost is higher. This was the single factor that kept me from giving these rims a serious thought. Again, you get what you pay for.
    Enve certainly claims that molded holes are superior. They probably are. But if these rims aren't failing at the eyelets, then this isn't a factor.

    Do we know if drilled eyelets result in more problems than molded eyelets? Or could it be an unsubstantiated or exaggerated marketing claim? For example, straight pull spokes are theoretically stronger. Yet everyone seems perfectly happy with the strength of standard j-bend spokes. The same could be true for drilled eyelets in carbon rims. So the honest question is... is there any evidence that drilled holes are a problem?

    What concerns me more about light bicycle rims are that the eyelets are drilled perfectly perpendicular. This results in more localized stress on the nipple, spoke, and rim. It also results in bent spoke ends. But again, is this actually a problem? I honestly don't know but my guess is that it doesn't matter, just like j-bend spokes.

  15. #2590
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    Quote Originally Posted by Simplemind View Post
    Yep, at least they did in 2010, in Tijuana. I think the Easton wheels, except for their hubs, have a pretty good reputation.

    So if Easton wheels/rims have a good reputation and they drill their rims, why should this point of view not be attached to the LB rims. I suspect that if LB had Easton stickers slapped all over their rims people would not question the strength and build quality and would be willing to pay more for them. Again we are back to the view that they are Chinese so inferior in some way.

  16. #2591
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    I believe LB and everyone else (which is almost everyone else) that drills the holes compensates by making that part of the rim thicker and that is why your nipples don't stick out quite as much as they would on an Enve wheel. That lets Enve wheels be relatively lighter all else being equal.

    That being said, Enve rims cost over $800 each and LB rims are less than $200 each landed. The marginal difference to me is nowhere near the marginal cost difference. Most of the rest of the industry including Zipp drill their holes in most of their rims and the practice of molding them is a recent development as the skills necessary to do this have just been developed.

    The other side of the argument is that if I had over $1600 worth of rims on my bike I might be too afraid of damaging the rims to do all the stuff I do. I can ride the cr#p out of these and so what if I break a $200 rim every couple of years. I will have way more fun trying to tear these up than worrying I might scratch my Enve logo up.
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  17. #2592
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    Quote Originally Posted by yourdaguy View Post
    I believe LB and everyone else (which is almost everyone else) that drills the holes compensates by making that part of the rim thicker and that is why your nipples don't stick out quite as much as they would on an Enve wheel. That lets Enve wheels be relatively lighter all else being equal.

    That being said, Enve rims cost over $800 each and LB rims are less than $200 each landed. The marginal difference to me is nowhere near the marginal cost difference. Most of the rest of the industry including Zipp drill their holes in most of their rims and the practice of molding them is a recent development as the skills necessary to do this have just been developed.

    The other side of the argument is that if I had over $1600 worth of rims on my bike I might be too afraid of damaging the rims to do all the stuff I do. I can ride the cr#p out of these and so what if I break a $200 rim every couple of years. I will have way more fun trying to tear these up than worrying I might scratch my Enve logo up.
    Well put!

  18. #2593
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    Quote Originally Posted by agentorangemen View Post
    That post contains just two data points showing what I would deem as in improper way to measure nipple pull out force and give maximum spoke tension guidelines.

    In this configuration you are going to have bending of the rim section as well as "nipple pull out" damage accumulation. The evidence of bending is in the nonlinear load vs. crosshead displacement curve. The evidence of damage accumultion is the crack pop-in event associated with the load drop at ~ 300 kgf.

    An appropriate test would be to fixture the rim section rigidly to the t-table near the spoke hole of interest and actually pull a nipple and threaded spoke through the hole with gripping on the spoke itself. If spoke elongation or nipple failure is a problem before rim failure then you've found the weakest link and the nipple holes are strong enough.

    Testing like this brings into question proper quality control metrics and data tracking/interpretation.

    These rims are now off the table for me.

    Thank you for the post Pauly.
    Not questioning your kung-fu here, because I don't do failure analysis as a professional, but if I'm testing when a nipple pulls out (as in rim failure), what would I care if spokes or nipples break/crack? Wouldn't I ultimately want to see if the rim will give at their rated kgf, and how many factors of safety I can get before it gives?
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  19. #2594
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    Quote Originally Posted by yourdaguy View Post
    I believe LB and everyone else (which is almost everyone else) that drills the holes compensates by making that part of the rim thicker and that is why your nipples don't stick out quite as much as they would on an Enve wheel. That lets Enve wheels be relatively lighter all else being equal.

    That being said, Enve rims cost over $800 each and LB rims are less than $200 each landed. The marginal difference to me is nowhere near the marginal cost difference. Most of the rest of the industry including Zipp drill their holes in most of their rims and the practice of molding them is a recent development as the skills necessary to do this have just been developed.

    The other side of the argument is that if I had over $1600 worth of rims on my bike I might be too afraid of damaging the rims to do all the stuff I do. I can ride the cr#p out of these and so what if I break a $200 rim every couple of years. I will have way more fun trying to tear these up than worrying I might scratch my Enve logo up.
    nipples don't stick out of an Enve rim
    the hole is only as big as the spoke
    Its a small point but just saying

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  20. #2595
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    Quote Originally Posted by yourdaguy View Post
    That being said, Enve rims cost over $800 each and LB rims are less than $200 each landed.
    Human nature to justify our decisions. I had a set on order, but when I started seeing the number and type of failures on this thread, I decided that the hassle factor with rebuild and warranty was just not worth it TO ME. I only chimed in to articulate one person's perspective.

    Quote Originally Posted by Jimmy V View Post
    Well put!
    Well put indeed!

  21. #2596
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    fact check

    Quote Originally Posted by yourdaguy View Post
    I believe LB and everyone else (which is almost everyone else) that drills the holes compensates by making that part of the rim thicker and that is why your nipples don't stick out quite as much as they would on an Enve wheel. That lets Enve wheels be relatively lighter all else being equal.
    1) ENVE wheels use internal nipples, so they don't stick out at all.
    2) My "wider" 29er rims are as light as the 18mm ID ENVE XC rims and over 50g each lighter than the comparable (width wise) ENVE AM rims.

    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  22. #2597
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    Quote Originally Posted by meltingfeather View Post
    1) ENVE wheels use internal nipples, so they don't stick out at all.
    2) My "wider" 29er rims are as light as the 18mm ID ENVE XC rims and over 50g each lighter than the comparable (width wise) ENVE AM rims.

    According to the claimed weights on their websites, it seems that the companies are producing wheels that are pretty much comparable in terms of weight given the internal width.

    LB 29XC 21mm internal width = 370g
    ENVE 29XC 18mm internal width = 385g
    LB 29wider 23mm internal width = 390g
    LB 29wider+stronger 23mm internal width = 420g
    ENVE 29AM 24mm internal width = 440g

  23. #2598
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    Quote Originally Posted by dfiler View Post
    According to the claimed weights on their websites, it seems that the companies are producing wheels that are pretty much comparable in terms of weight given the internal width.

    LB 29XC 21mm internal width = 370g
    ENVE 29XC 18mm internal width = 385g
    LB 29wider 23mm internal width = 390g
    LB 29wider+stronger 23mm internal width = 420g
    ENVE 29AM 24mm internal width = 440g
    OK... so then maybe you can explain his claim that ENVE wheels are relatively lighter due to the increased spoke bed thickness, all else equal, even though the rims are heavier.
    TIA
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  24. #2599
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    Quote Originally Posted by dfiler View Post
    According to the claimed weights on their websites, it seems that the companies are producing wheels that are pretty much comparable in terms of weight given the internal width.

    LB 29XC 21mm internal width = 370g
    ENVE 29XC 18mm internal width = 385g
    LB 29wider 23mm internal width = 390g
    LB 29wider+stronger 23mm internal width = 420g
    ENVE 29AM 24mm internal width = 440g
    You should take into account the 35g of Bonti strip an LB rim requires, whereas with an ENVE you can use a Gorila tape (17g) or even Stan's (5g).

  25. #2600
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    OK, I'll chime in again. Again, imho, the greatest benefit of carbon rims for a 29er application is lateral stiffness, not weight. So the argument about a couple of grams difference is a moot point, at least TO ME.


    Quote Originally Posted by Climber999 View Post
    You should take into account the 35g of Bonti strip an LB rim requires, whereas with an ENVE you can use a Gorila tape (17g) or even Stan's (5g).
    Good point!

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