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  1. #1
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    Bead hook-less rims, are they the future?

    Hey guys, I was just reading about Specialized's new Roval wheels which comes with hookless carbon rims. Any of you guys tried it? I'm just trying to get that idea to sit in it's quite hard to imagine you can secure the tire without any bead hooks.

  2. #2
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    I'd want to see a lot more consistency in bead shape, strength, and diameter for tubeless But hookless rims are nothing new.

  3. #3
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    Difficult to make a durable carbon bead hook. I doubt you'll see hook-less aluminum rims any time soon.
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  4. #4
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    Bead hook-less rims, are they the future?

    Aren't vehicle wheels hookless/tubeless?

    Edit: The engineer inside me thinks that the concept works well in a very ASTM-guided, static environment like the automotive industry. In the bike industry, not so much. Lots of tweaking, rapid technology development and implementation, combined with a variable stress input (terrain). Show me a dude riding these at Red Bull Rampage and I'll be a believer in the concept. For light XC, it might work.
    Last edited by MTBeing; 01-31-2013 at 06:16 PM.
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  5. #5
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    They are not new. They are old technology that has been discredited and discontinued. Next Specialized will bring back cottered cranks and quill stems.

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    Quote Originally Posted by jasonwfreak View Post
    Hey guys, I was just reading about Specialized's new Roval wheels which comes with hookless carbon rims. Any of you guys tried it? I'm just trying to get that idea to sit in it's quite hard to imagine you can secure the tire without any bead hooks.
    Only if the tires are specifically designed to work with them. Current mtb (and road) tires are not.

    Quote Originally Posted by MTBeing View Post
    Aren't vehicle wheels hookless/tubeless?

    Edit: The engineer inside me thinks that the concept works well in a very ASTM-guided, static environment like the automotive industry. In the bike industry, not so much. Lots of tweaking, rapid technology development and implementation, combined with a variable stress input (terrain). Show me a dude riding these at Red Bull Rampage and I'll be a believer in the concept. For light XC, it might work.
    Exactly. The tire and rim are designed to work together. The bicycle ISO spec is fairly good as far as it applies to tubed use, and the UST spec is ISO approved for tubeless.
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  7. #7
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    Rim makers will approach tire makers to come up with a new standard if it can be a win-win for both, that's how the industry works. "Hookless Ready" tires? I'm guessing Specialized will come up with their own version(?less + 2bliss, get it?) first if it works well for them. and whichever oem factory that makes their tire will too.

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    No need for hookless ready tires. I have been using the new Roval rims with Rocket Rons for a few rides now and have yet to have an issue with them. Even when I sliced a side wall and the tire was loosing air it stayed on. I know several people that have been using the rims with zero issues as well.

    Very east to set up tubeless too. I experienced absolutely zero leaks from around the bead.

  9. #9
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    Quote Originally Posted by shiggy View Post
    Only if the tires are specifically designed to work with them. Current mtb (and road) tires are not.
    I can't speak for road tires, but the mtbr reviewers were able to touch a c-clamp together on a tire mounted tubeless on hookless rims. I would have no reservations riding a set of hookless rims.

  10. #10
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    Quote Originally Posted by Berkley View Post
    Difficult to make a durable carbon bead hook. I doubt you'll see hook-less aluminum rims any time soon.
    Take a good look at the Stan's Flow
    EX... Not much hook at all in fact before I put tires on mine I googled the hell out if them to make sure they weren't some sort of goofy factory defect

  11. #11
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    Bead hooked rims and clincher tire beads to mate, were started in the early '70's for tubed tires needing high pressures, 65 to 100+ psi.

    If running tubeless converted clincher bead tires with sealant, bead hooks have absolutely no benefit to keep the tire on the rim.

    With tubeless conversions of clincher tires the tire bead simply must not stretch or be off center to reach over the edge of the rim to blow off from air pressure. Rims designed to be tubeless ready or TR are now very common, having wide inside bead shoulders on both sides of the middle deep channel to be sure the tire bead is centered inside well below the edge of the rim.

    UST bead hooks mate with UST tire beads. The hook near the edge of the rim is useful for very high tire pressures, over 65 psi. And the UST hooks on the rim inside shoulders next to the center channel prevent the bead from squirming inward enough to fall off the shoulder and burping air or blowing off the rim during cornering when tubeless, and the shoulder bead hooks keeps the bead under the rim's edge hooks when tubeless without sealant and using higher air pressures.

    If inflating under 65 psi and using TR bead centering rims, then bead hooks are useless. We will probably see rims without bead hooks become the standard for mountain bikes in a few years, and tire bead design will follow.

    Having no bead hooks allows a wider inside rim width. And the rim edge can be thicker and more durable without adding more weight compared to a rim with bead hooks.

  12. #12
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    Quote Originally Posted by msrothwe View Post
    I can't speak for road tires, but the mtbr reviewers were able to touch a c-clamp together on a tire mounted tubeless on hookless rims. I would have no reservations riding a set of hookless rims.
    I would not. There is more to it than that.
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  13. #13
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    In response to Derby, I still think hookless rims are a bad idea. On the point that hooks are needed for 65+ psi : That is 65 psi on a road tire. The hoop stress, or the force that the tire sidewall tries to pull upwards on the bead, is proportional to both pressure and tire diameter. So the sidewall upwards pulling force for a 2" 32 psi mtb tire is the same as that of a 1" tire at 65 psi.

    Obviously, the hookless design has no protection at all from preventing the tire bead from lifting upwards slightly. This is critically important because if it lift upwards even slightly, you lose the sealing effect of the bead against the rim bed, and air can get underneath the bead, contributing to an additional upwards as well as inwards force. (Running a tube would prevent this, btw.)

    So the hookless design is even worse than Stan's in that it totally relies on circumferential bead tension to keep the tire tightly against the rim. How do you know it is enough under high cornering forces where there is additional tugging on the tire?

    UST rim and UST tire is a very good combination because the bead hook is at exactly the right height to keep the tire bead pressed down against the rim. Further, in the case of a tire bead or sidewall failure, or when using a tube-full tire, you can still use an inner tube, and the bead hooks will still keep the tire on.

  14. #14
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    Quote Originally Posted by beanbag View Post
    In response to Derby, I still think hookless rims are a bad idea. On the point that hooks are needed for 65+ psi : That is 65 psi on a road tire. The hoop stress, or the force that the tire sidewall tries to pull upwards on the bead, is proportional to both pressure and tire diameter. So the sidewall upwards pulling force for a 2" 32 psi mtb tire is the same as that of a 1" tire at 65 psi.

    Obviously, the hookless design has no protection at all from preventing the tire bead from lifting upwards slightly. This is critically important because if it lift upwards even slightly, you lose the sealing effect of the bead against the rim bed, and air can get underneath the bead, contributing to an additional
    upwards as well as inwards force. (Running a tube would prevent this, btw.)

    So the hookless design is even worse than Stan's in that it totally relies on circumferential bead tension to keep the tire tightly against the rim. How do you know it is enough under high cornering forces where there is additional tugging on the tire?

    UST rim and UST tire is a very good combination because the bead hook is at exactly the right height to keep the tire bead pressed down against the rim. Further, in the case of a tire bead or sidewall failure, or when using a tube-full tire, you can still use an inner tube, and the bead hooks will still keep the tire on.
    BikeRumor summed it up really well.

    "With a snug/strong (tubeless or tubeless-ready bead), the inside diameter of the tire (at the bead) canít climb up over the rim- it simply isnít big enough. In order to install or remove tires, part or all of the bead must sit down in the center channel, providing enough slack to get another section of the bead over the wall. No bead hook will keep an insufficiently-snug tubeless tire in place. This is a big reason that companies advise against using tire levers with tubeless/tubelish tires: they can stretch the bead and increase the chance of a blowoff."

    I have experienced this with tires before. I had a set of X-kings and nothing would keep those things seated. Blow offs are almost always attributed to the tire not the rim.

  15. #15
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    Quote Originally Posted by beanbag View Post
    In response to Derby, I still think hookless rims are a bad idea. On the point that hooks are needed for 65+ psi : That is 65 psi on a road tire. The hoop stress, or the force that the tire sidewall tries to pull upwards on the bead, is proportional to both pressure and tire diameter. So the sidewall upwards pulling force for a 2" 32 psi mtb tire is the same as that of a 1" tire at 65 psi.

    Obviously, the hookless design has no protection at all from preventing the tire bead from lifting upwards slightly. This is critically important because if it lift upwards even slightly, you lose the sealing effect of the bead against the rim bed, and air can get underneath the bead, contributing to an additional upwards as well as inwards force. (Running a tube would prevent this, btw.)

    So the hookless design is even worse than Stan's in that it totally relies on circumferential bead tension to keep the tire tightly against the rim. How do you know it is enough under high cornering forces where there is additional tugging on the tire?

    UST rim and UST tire is a very good combination because the bead hook is at exactly the right height to keep the tire bead pressed down against the rim. Further, in the case of a tire bead or sidewall failure, or when using a tube-full tire, you can still use an inner tube, and the bead hooks will still keep the tire on.
    Good point about the relative tire pressures to tire size and bead stretching force pulling the bead up from the rim, for those needing high tire pressures. Is the pulling pressure 1:1 rate to tire diameter, same rim width?

    Yes, agree, bead hooks are only useful with an inner tube and higher pressures, or tubeless only if UST bead or TR bead with UST rim.

    I time time will soon tell. The Specialized hookless rims are not UST. They are pretty light in weight. I imagine many will use them with light 2.0 tires and higher pressures than 32 psi for XC racing, tubeless and with tubes, repeating failures would be broadcast soon. Although Specialized probably did test with high pressures before investing major dollars in these rims.

  16. #16
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    In the last video Specialized uploaded of the last WC they said that the new roval wheels are bead hook-less!!

    I don't think Specialized will install on s-works bikes and in the market around the world a Roval wheels that are useless or won't work!!
    They didn't say anything about new tires or special tires with this new system they are using the sworks 2bliss tires!!

    I will buy the 2014 SW stumpy and I'm scared too that this new rim could fail in races I use my tires with very low pressure 25-26 psi but I just trust in the brand!!!!

  17. #17
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    Quote Originally Posted by PainkillerSPE View Post
    No need for hookless ready tires. I have been using the new Roval rims with Rocket Rons for a few rides now and have yet to have an issue with them. Even when I sliced a side wall and the tire was loosing air it stayed on. I know several people that have been using the rims with zero issues as well.

    Very east to set up tubeless too. I experienced absolutely zero leaks from around the bead.
    Well you are the first person who have tested the new wheels!!!
    Cool!! Are they 1370 g like they said?? I will use sworks tires hope this new system works perfect in all conditions!!

  18. #18
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    Quote Originally Posted by andresco50 View Post
    Well you are the first person who have tested the new wheels!!!
    Cool!! Are they 1370 g like they said?? I will use sworks tires hope this new system works perfect in all conditions!!
    Mine are the heavier Roval Control Carbons. But in terms of the hookless rim, don't worry about it at all. I have over 6 months of constant use on mine and not a single problem. I run my tires around 21-23 PSI. I completely trust the wheelset and have won several races with them.

    Both wheels are still going strong and have never needed truing, despite several really bad wrecks. It's a very solid dependable wheelset that's worth every penny.

  19. #19
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    Hook-less is fine as long as the tire is designed for it. The tire needs a strong enough and small enough bead so that it will not stretch off the rim. Ideally there should be a max pressure listed for this combination with a significant safety factor. Low pressure is ideal for this. Notubes rims are basically hook-less and they also have a much shorter sidewall than the Specialized rims. Notubes rims work for most people at low pressure, but at higher pressures with larger riders tires have been known to blow off the rim.

  20. #20
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    Quote Originally Posted by changingleaf View Post
    Hook-less is fine as long as the tire is designed for it. The tire needs a strong enough and small enough bead so that it will not stretch off the rim. Ideally there should be a max pressure listed for this combination with a significant safety factor. Low pressure is ideal for this. Notubes rims are basically hook-less and they also have a much shorter sidewall than the Specialized rims. Notubes rims work for most people at low pressure, but at higher pressures with larger riders tires have been known to blow off the rim.
    That's totally true once I inflated a sw renegade tire with so much pressure that the tire blow off the NOTUBES rim sounded like an explosion!! and all the sealant was in the roof and in my face!!

    Now changingleaf said that low pressure is ideal for this type of rims but how much low is safe to run?!! I don't know at what pressure I'm running but maybe is about 24 25psi!!!

    I'm deciding what to do right now.. 1.-buy a complete 2014 s-works stumpy bike with this new hookless roval wheelset or 2.- Buy the frameset and install it with stans wheelset.

    Right now I have a stans ztr crest wheelset on my bike and they are really awesome no problems just perfect!!!

  21. #21
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    Quote Originally Posted by derby View Post
    Good point about the relative tire pressures to tire size and bead stretching force pulling the bead up from the rim, for those needing high tire pressures. Is the pulling pressure 1:1 rate to tire diameter, same rim width?

    Yes, agree, bead hooks are only useful with an inner tube and higher pressures, or tubeless only if UST bead or TR bead with UST rim.

    I time time will soon tell. The Specialized hookless rims are not UST. They are pretty light in weight. I imagine many will use them with light 2.0 tires and higher pressures than 32 psi for XC racing, tubeless and with tubes, repeating failures would be broadcast soon. Although Specialized probably did test with high pressures before investing major dollars in these rims.
    Derby: Right a big company needs a lot of tests to produce something!! so like u said the hook only works with high pressure like 65psi!! I'm in XC racing and use 24 psi not 30psi hope my sworks tires won't blow off the rims in the downhills

  22. #22
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    here is a great review about the 2013 hookless roval control 29 wheelset check it out

    Specialized Roval Control 29 Carbon Mountain Bike Wheels, Tested | Bicycling Magazine

    and I love this part:

    "I dropped tire pressure down as low as 16 psi on one ride. Even with so little air, the tires remained stuck to the rims and didnít burp. After the snow melted, the trails bared their teeth again and I continued to run low pressure (about 18-22 psi), but I never flatted and the tires never flinched. After weeks of hard riding, the rims emerged without cracks or dents."

    and here is a review from here mtbr!!!!!

    2013 Specialized Roval Control 29 Carbon Wheels for $1200 | Mountain Bike Review
    Last edited by andresco50; 08-17-2013 at 02:56 PM.

  23. #23
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    andresco50. The bead hook was not designed to secure the tire at low pressure, it is strictly designed to keep the tire from blowing off at higher pressures (and even there you will find a limit), so go as low as you can. You will know the pressure you are running is too low if you dent your rim, or burp air on bumps or hard corners or feel the tire folding in corners.

    Even without a bead hook most modern tires will never blow off when inflated under 35psi and many will go much higher before blowing off. The bead hook then becomes just added weight so specialized removed it and other brands are making theirs smaller.

    Unless Specialized changed the inside of their rims tires do not inflate nearly as easily on them as they do on stan's rims. I good functioning rim and tire combination will allow you to inflate the tire with a floor pump. If a compressor is necessary it's not an ideal setup.

  24. #24
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    obviously the materials/ strength is different but if a street bike can use hook less rims i think we can get away with them with a properly designed tire on our bicycles.

  25. #25
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    Bead hook-less rims, are they the future?

    Quote Originally Posted by b-kul View Post
    obviously the materials/ strength is different but if a street bike can use hook less rims i think we can get away with them with a properly designed tire on our bicycles.
    Agreed, but current performance tires are not designed for hookless bead rims.
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  26. #26
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    Quote Originally Posted by b-kul View Post
    obviously the materials/ strength is different but if a street bike can use hook less rims i think we can get away with them with a properly designed tire on our bicycles.
    The beadless road wheels I remember had a Max inflation of 80 lbs. More than that and glue would probably need to be involved.

  27. #27
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    Quote Originally Posted by b-kul View Post
    obviously the materials/ strength is different but if a street bike can use hook less rims i think we can get away with them with a properly designed tire on our bicycles.
    definitely in road wheels u have to use the hook!! I use 110psi in my road bike!!! with hookless rims the tire never will suport that pressure it will blow off!!

  28. #28
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    Quote Originally Posted by changingleaf View Post
    andresco50. The bead hook was not designed to secure the tire at low pressure, it is strictly designed to keep the tire from blowing off at higher pressures (and even there you will find a limit), so go as low as you can. You will know the pressure you are running is too low if you dent your rim, or burp air on bumps or hard corners or feel the tire folding in corners.

    Even without a bead hook most modern tires will never blow off when inflated under 35psi and many will go much higher before blowing off. The bead hook then becomes just added weight so specialized removed it and other brands are making theirs smaller.

    Unless Specialized changed the inside of their rims tires do not inflate nearly as easily on them as they do on stan's rims. I good functioning rim and tire combination will allow you to inflate the tire with a floor pump. If a compressor is necessary it's not an ideal setup.
    Great response changingleaf thanks!! yeah definitely I have to give em a try!! I have more confidence now!!

    The guy in the mtbr review of the 2013 roval control wheelset inflate the tires just with a pump!! awesome!!!

    2013 Specialized Roval Control 29 Carbon Wheels for $1200 | Mountain Bike Review

    Also no tire levers needed... I think u don't have to use tire levers with these system I do not want to stretch the tire!!

  29. #29
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    Guys for more info here is a response from Roval JOE from specialized... I asked him the same issues about running these hookless rims with low pressure and here is the response!! so guys read it!! the comments from the beginning of this thread are totally against this technology!! now I am convinced that they definitely will work and they are awesome!!

    "Hey Andresco- have a look in the first couple pages of this thread for an explanation of why the rim w/out bead hooks keeps the tire on. For a little history, we introduced this design for model year 2013, so the rims have been in the market (thousands of them), without any problems in keeping tires on. You'll notice all the comments from magazine reviews and comments from actual owners here on MTBR are all positive, reporting no issues with keeping tires on. You'll also notice that the only people commenting on the "theoretical problems with tire compatibility" with these rims are people who A)do not own a set, and B)have never tried them. We have tested many manufacturers tires on these rims with no problems. You will be able to run the same tire pressure with these rims as your standard rims."

  30. #30
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    Quote Originally Posted by andresco50 View Post
    now I am convinced that they definitely will work and they are awesome!!
    knock yourself out, figuratively speaking.

  31. #31
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    So.....someone just posted that he owns a set of Roval wheels and had a flat recently. When that happens the sides of the tires completely unseat and you are not able to air them up while on the trail. Seems you need two pairs f hands even with an inner tube to hold the whole thing together while you pump it full of air to get the sides to seat. Anyone else have this problem or do you guys not worry about stuff like this till you do get a flat or blowout?

    I was riding tubeless in jamaiaica recently and picked up a huge nail that was not able to be sealed with Stan's. I was in the middle of no where and luckily had a tube.

  32. #32
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    Quote Originally Posted by YaMon View Post
    So.....someone just posted that he owns a set of Roval wheels and had a flat recently. When that happens the sides of the tires completely unseat and you are not able to air them up while on the trail. Seems you need two pairs f hands even with an inner tube to hold the whole thing together while you pump it full of air to get the sides to seat. Anyone else have this problem or do you guys not worry about stuff like this till you do get a flat or blowout?

    I was riding tubeless in jamaiaica recently and picked up a huge nail that was not able to be sealed with Stan's. I was in the middle of no where and luckily had a tube.
    Put a tube in them and pump them up. No difference. The biggest downside I have had someone mention was if you like to pull the valve core to refresh the sealant. The tires will fall away from the sides and require a reseat which may or may not be a pain depending on how well your tire/rim interface is working and what your source of air is.
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  33. #33
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    in the MTBR review vid this guy inflate the tire with a pump!! definitely will inflate with a co2 cartridge in marathon races I always carry a tube

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    For these rims do the tires need to be ust or tlr, or can just a regular tire be used with stans sealant, I am going to go carbon but undecided about clincher or hookless a lot of my tires are just regular?

  35. #35
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    If you're using hookless rims I recommend UST or tubeless-ready for their extra bead strength. If you are lightweight and keeping the psi under 30 then tube type tires will be fine.

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    You don't need UST. I have used both Tubeless ready and standard tires without issue.

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    My experience may or may not generalize to other hookless rims, tires, sealant, or riding terrain; I'm ~190lb BTW. I have Derby 40mm 650b rims on my road bike. I've used two sets of tube tires mounted tubeless with Orange Seal sealant at 30-35psi, Grand Bois Hetre 42mm nominal, and Pacenti Pari-Moto 38mm nominal, both are skinwall casings with flexible beads. The Hetre tires had been mounted tubed on a hooked rim in the past with tires levers or bead jack multiple times, so I believe their beads were well stretched. I also mounted the Hetres tubed on the Derby rim for a time. The reason the Hetre tires were mounted multiple times was because with each tire/tube puncture, the tire had to be removed, offending object removed, tube patched, and tire re-installed. Orange Seal eliminated that hassle. I experienced no burps or failures with these tires designed for tubes mounted on Derby's hookless rim run tubeless at medium-low tire pressure.

    As for one safety concern, I suggest evaluating a tubeless rim based on the bead lock and shelf. The Derby rim has a pronounced hump. The first time you remove a tire after it's been mounted on a Derby rim will instill a great deal of confidence the tire will stay put if it was to deflate rapidly while in motion.

  38. #38
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    I am about 175 lbs fully geared up. & I should mention the majority of my tires are folding bead. I will probably switch over to ust, tlr tires but I am planning on getting two sets of rims 29 & 27.5 & really don't want to have to invest in all new tires at the same time

  39. #39
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    Are bead hook rims really that bad? How many bead hook carbon rims actually failed?
    Is this not a solution for a non existent problem?
    Just asking...

  40. #40
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    I just mounted up a set of tires, Specialized Ground Control 2Bliss Grid Front, and Specialized Fast Trak 2Bliss Grid Rear, to a new set of these Hookless 29er Wheels. They mounted up easier than almost any other setup I've installed previously. However, the one thing that I did not notice was any king of a "pop" indicating the bead set. Is this to be expected since the wall of the rim is pretty much vertical and there is no hook to "pop" into?

    I did not go over 40 psi because I have had some bad luck in the past year of blowing tires off of rims (mostly because I tried to set up tubeless in less than 30 degree weather), but this left me pretty gunshy.
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  41. #41
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    what maintains the "roundness" of the tire with a hookless rim? I have run Slant Six tires tubeless at 25-30lbs and had the tire blow off the rim for no apparent reason... When the hookless rim does fail can a tube be used to get you back to civilization?!!

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    If you ever blow a tyre off any rime just put another wrap of rim tape around the rim, this increases the effective tyre seat diameter and will stop it happening again.

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    Bead hook-less rims, are they the future?

    Quote Originally Posted by otiswood View Post
    what maintains the "roundness" of the tire with a hookless rim? I have run Slant Six tires tubeless at 25-30lbs and had the tire blow off the rim for no apparent reason... When the hookless rim does fail can a tube be used to get you back to civilization?!!
    Yes, you can run a tube.


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    Quote Originally Posted by derby View Post
    Is the pulling pressure 1:1 rate to tire diameter, same rim width?
    Just to get a definitive answer to this, the tension maintained in the bead varies independently and linearly with both rim width and rim diameter. Maximum tire width relative to rim width will also increase bead tension but at a less than linear but greater than 0 rate due to the componentwise breakdown of non-radial forces.

    The radial forces appear as follows:

    http://www.efunda.com/formulae/solid...lindricalC.gif

    whereby the central vertical line of symmetry corresponds to cutting the wheel into two halves. For a bicycle wheel, imagine most of the central vectors are not present since the majority of the wheel volume is spokes instead of pressurized volume.

  45. #45
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    Cool-blue Rhythm

    Quote Originally Posted by Berkley View Post
    Difficult to make a durable carbon bead hook. I doubt you'll see hook-less aluminum rims any time soon.
    ax-lightness: SRT CC 29er Clincher

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  46. #46
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    Any thoughts on this now?

    I see that Enve just released some hook-less rims-

    Has the tire issue been resolved?

    ~JRA

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    Quote Originally Posted by J_R_A View Post
    Any thoughts on this now?

    I see that Enve just released some hook-less rims-

    Has the tire issue been resolved?

    ~JRA
    I have gotten my hookless rims from Light Bicycles & have mounted a tr & a standard pancenti neo moto with no issues on either I only got one ride in so far but am loving the wider rims seems they really help the stability of the tires

  48. #48
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    Quote Originally Posted by synnie View Post
    I have gotten my hookless rims from Light Bicycles & have mounted a tr & a standard pancenti neo moto with no issues on either I only got one ride in so far but am loving the wider rims seems they really help the stability of the tires
    How's it riding ? What tires do you have on it ? Is it the 30mm rims or 35mm ?

  49. #49
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    Hahaha at anyone who thinks bead hooks are necessary on rims with a tubeless profile (shoulder that the bead sits on). Just think about it for a minute. The only way the bead is gonna slip up over the sidewall is if the opposite side can get down off the shoulder into the channel. Even with no air in the tire it takes considerable force to push the bead down off the shoulder. My dirtbike is hookless and runs 8psi. My van is hookless and runs 60 psi. No worry beef curry.

    The synopsis is: Bead shoulders replaced bead hooks. Since we want rims that are easy to mount and don't burp tubeless bead shoulders are here to stay. Bead hooks are now useless and compromise strength on aluminum and carbon rims and increase manufacturing cost on carbon rims. Bead hooks are a thing of the past for tubeless rims and hookless channel and shoulder equipped tubeless rims don't require any changes to current tire specs or tolerances.
    Keep the Country country.

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    Sure... but what happens when it goes all wrong?

    Quote Originally Posted by andresco50 View Post
    Guys for more info here is a response from Roval JOE from specialized... I asked him the same issues about running these hookless rims with low pressure and here is the response!! so guys read it!! the comments from the beginning of this thread are totally against this technology!! now I am convinced that they definitely will work and they are awesome!!

    "Hey Andresco- have a look in the first couple pages of this thread for an explanation of why the rim w/out bead hooks keeps the tire on. For a little history, we introduced this design for model year 2013, so the rims have been in the market (thousands of them), without any problems in keeping tires on. You'll notice all the comments from magazine reviews and comments from actual owners here on MTBR are all positive, reporting no issues with keeping tires on. You'll also notice that the only people commenting on the "theoretical problems with tire compatibility" with these rims are people who A)do not own a set, and B)have never tried them. We have tested many manufacturers tires on these rims with no problems. You will be able to run the same tire pressure with these rims as your standard rims."

    While I agree, there are nearly zero reports of failure for hook-less rims, the idea is to have additional security built into the rim in case the air pressure suddenly drops, or suddenly increases with a big hit, and the tire to stay on the bead (if at all possible). I do not own a set of hook-less rims, but find it a hard point to argue that having the hook on a rim... with that tires bead settled into it... and sealant nestled all around it... isnt the "best possible way" to prevent a burp, tire blow-off, etc.


    Again, not arguing that hook-less won't do the job, but I personall feel a whole lot better with it there. If carbon manufacturers can't replicate that without creating a point of failure in their rims, then I guess I won't be on carbon rims anytime soon.

  51. #51
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    I think there is a little confusion out there between a bead hook and a bead lock and their purpose. Many rim manufacturers either take this for granted or don't want to explain it for one reason or another.

    A bead hook is a HOOK that comes around the top of the rim. It is for safety. It is designed to keep the tire from blowing off the rim at high pressures. Tires used to vary considerably in size, and the strength of their beads were not very good. With the extra Kevlar now in use on tubeless and tubeless ready beads the hook is not necessary. Also, running lower pressure makes the hook less necessary. Very old bicycle rims did not have bead hooks because they always used tires with a strong wire bead. Automobile rims do not have hooked beads because they use a strong cable bead.

    A bead hook is not going to prevent burping. Burping happens when a tire bead is pushed inward to the center channel of the rim and air escapes. Removing the bead hook allows the tire to expand wider. Another advantage of removing the bead hook is too save unnecessary weight. Notubes has had a minimal bead hook for years. The new DT Swiss rims are using a minimal bead hook.

    A bead-lock is a bump on the horizontal bead-seat. Automobile rims and UST rims have a bead lock (UST rims also have a bead hook for safety). Most tubeless-ready rims do not have a bead lock. They simply have a wide horizontal seat that allows the tire bead to act like an o-ring sealing tightly on the rim. If you look closely at a derby rim it of course does not have a bead hook, but it does have a raised area on the inside of each bead seat which act as a bead lock. The bead lock attempts to prevent the tire bead from being pushed into the center channel of the rim during a side load.

    If the tire is too loose or the force too high it will burp anyway regardless of the type of rim you're using.
    Last edited by changingleaf; 02-07-2015 at 12:16 PM. Reason: correction

  52. #52
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    Quote Originally Posted by changingleaf View Post
    I think there is a little confusion out there between a bead hook and a bead lock and their purpose. Many rim manufacturers either take this for granted or don't want to explain it for one reason or another.

    A bead hook is a HOOK that comes around the top of the rim. It is for safety. It is designed to keep the tire from blowing off the rim at high pressures. Tires used to vary considerably in size, and the strength of their beads were not very good. With the extra Kevlar now in use on tubeless and tubeless ready beads the hook is not necessary. Also, running lower pressure makes the hook less necessary. Very old bicycle rims did not have bead hooks because they always used tires with a strong wire bead. Automobile rims do not have hooked beads because they use a strong cable bead.

    A bead hook is not going to prevent burping. Burping happens when a tire bead is pushed inward to the center channel of the rim and air escapes. Removing the bead hook allows the tire to expand wider. Another advantage of removing the bead hook is too save unnecessary weight. Notubes has had a minimal bead hook for years. The new DT Swiss rims are using a minimal bead hook.

    A bead-lock is a bump on the horizontal bead-seat. Automobile rims and UST rims have a bead lock (UST rims also have a bead hook for safety). Most UST rims do not have a bead lock. They simply have a wide horizontal seat that allows the tire bead to act like an o-ring sealing tightly on the rim. If you look closely at a derby rim it of course does not have a bead hook, but it does have a raised area on the inside of each bead seat which act as a bead lock. The bead lock attempts to prevent the tire bead from being pushed into the center channel of the rim during a side load.

    If the tire is too loose or the force too high it will burp anyway regardless of the type of rim you're using.

    Very good information. But the UST rim standard includes the dimensions for bead locks (commonly referred to as safety humps). And passenger, LT, ATV tires use wound wire beads, not cable.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  53. #53
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    Quote Originally Posted by joesrepsol View Post
    While I agree, there are nearly zero reports of failure for hook-less rims, the idea is to have additional security built into the rim in case the air pressure suddenly drops, or suddenly increases with a big hit, and the tire to stay on the bead (if at all possible). I do not own a set of hook-less rims, but find it a hard point to argue that having the hook on a rim... with that tires bead settled into it... and sealant nestled all around it... isnt the "best possible way" to prevent a burp, tire blow-off, etc.


    Again, not arguing that hook-less won't do the job, but I personall feel a whole lot better with it there. If carbon manufacturers can't replicate that without creating a point of failure in their rims, then I guess I won't be on carbon rims anytime soon.
    The additional security you feel is afforded by bead hooks is a little misguided. The bead hook will only serve to help prevent a tire blowing off the rim due to a weak and/or oversized bead (and even then it's only really effective when using an innertube. It will do nothing to prevent a tire from burping, losing air pressure, or any other type of failure.

    With the advent of UST and tubeless ready tires and rims, tire manufacturers were forced to increase the strength of their beads (also accounting for a factor of safety) and tighten the manufacturing tolerance of the bead diameter. Of course some companies had a rough time getting there (Schwalbe). But any quality tubeless ready or UST tire on the market these days is perfectly fine to use on a hookless rim at normal (intended) operating pressures. If you wish to buy tires of questionable quality, however, I'd recommend sticking with an innertube and rims with bead hooks.

    So in summation, if a quality tubeless ready or UST tire is to be used, rims with bead hooks are completely unnecessary. In fact, hookless beads are superior in that the internal width of the rim is greater, there is no stress riser at a critical location on the rim, and rims can be made stronger with no increase in weight. The fact that it is cheaper for the rim manufacturer is just topping on the cake. Give it a couple years and it'll be hard to find high-end hooked mtb rims.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  54. #54
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    Bead hook-less rims, are they the future?

    I'm sold on hookless. The theory makes sense and I've been riding a set of derby's for about 6 months. Not only have I had no issues, but removing a tire from these rims is far more difficult than any other rim I've ever seen. Due to the tight tolerances and tight bead lock. It's almost impossible to unseat the bead by hand (for me anyways, I have to step on the sidewall).


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    Bead hook-less rims, are they the future?

    I had Araya straight sided (hookless) rims a long time ago. You couldn't mount a Kevlar beaded tire on them without the tire blowing off. On steel beads, you had to be careful about max pressure. Sounds like another dumb ass idea, like carbon fiber rims are. Might as well combine two dumb assed ideas into one.

  56. #56
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    Quote Originally Posted by changingleaf View Post
    Most UST rims do not have a bead lock. They simply have a wide horizontal seat that allows the tire bead to act like an o-ring sealing tightly on the rim.
    This is totally incorrect, ALL UST spec rims include a bead lock
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    I believe what you meant is most non UST rims that are advertised as "Tubeless Ready" lack a bead lock. This would be true of Velocity, Pacenti, Stans, and some carbon models.

    I have noticed that many of the newer hookless carbon rims are now putting a ridge or bump that acts like a bead lock on their rims. Derby, Light Bicycle, and Ibis all include this feature.

  57. #57
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    You are correct. I meant to say "most tubeless-ready rims.." I corrected the post.

    The point is a bead hook is meant to keep the tire from being pushed outward.

    The bead-lock or bead hump is designed to the tire from being pushed inward and burping.

    With a strong enough bead a hook is not necessary.

  58. #58
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    Quote Originally Posted by MikeDee View Post
    I had Araya straight sided (hookless) rims a long time ago. You couldn't mount a Kevlar beaded tire on them without the tire blowing off. On steel beads, you had to be careful about max pressure. Sounds like another dumb ass idea, like carbon fiber rims are. Might as well combine two dumb assed ideas into one.
    I'm curious; did you read my posts, or any others in this thread before posting your ill-informed opinion?
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

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    Bead hook-less rims, are they the future?

    Quote Originally Posted by bholwell View Post
    I'm curious; did you read my posts, or any others in this thread before posting your ill-informed opinion?
    Because you're wrong? Mainly opinion and conjecture with no supporting facts. Over 100 years of history says beaded rims are superior to straight sided rims. I don't see anything posted here to indicate otherwise.
    Last edited by MikeDee; 02-07-2015 at 04:18 PM.

  60. #60
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    MikeDee was speaking of "back in the old days", and he is correct.
    If tires have strong enough beads, then it should be ok to run them on a hookless rim. Since we are in a transition period with both old and new equipment, what I would like to see is that tires have some kind of a "hookless approved" rating, and for hookless rims to give a consumer warning that they are only designed to run these approved tires.

    Otherwise it will just be another case of "ghetto tubeless" where sometimes it works and sometimes you go to the hospital.

  61. #61
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    Quote Originally Posted by MikeDee View Post
    Because you're wrong? Mainly opinion and conjecture with no supporting facts. Over 100 years of history says beaded rims are superior to straight sided rims. I don't see anything posted here to indicate otherwise.
    What exactly did I say that was incorrect?

    Opinion and conjecture? I have over 5 years experience as a tire design and development engineer for a major tire manufacturer, and 8 years total as a tire design and development engineer. Your qualifications are...?
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  62. #62
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    Quote Originally Posted by beanbag View Post
    MikeDee was speaking of "back in the old days", and he is correct.
    If tires have strong enough beads, then it should be ok to run them on a hookless rim. Since we are in a transition period with both old and new equipment, what I would like to see is that tires have some kind of a "hookless approved" rating, and for hookless rims to give a consumer warning that they are only designed to run these approved tires.

    Otherwise it will just be another case of "ghetto tubeless" where sometimes it works and sometimes you go to the hospital.
    MikeDee is only correct about the past; not the present.

    "If the tires have strong enough beads..." is exactly what I said. Today's tubeless ready and UST tires are perfectly fine to run tubeless on hookless rims.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  63. #63
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    Bead hook-less rims, are they the future?

    Quote Originally Posted by bholwell View Post
    MikeDee is only correct about the past; not the present.

    "If the tires have strong enough beads..." is exactly what I said. Today's tubeless ready and UST tires are perfectly fine to run tubeless on hookless rims.
    Whatever... Isn't this whole thing a solution to a non problem? The OP was about Roval (Specialized) carbon wheels, which a Bicycling Magazine article I just read says cost $1800 a pair and was about making the sidewalls stronger (probably makes it easier for them to make a CF rim, truth be known). You can make the wall stronger by increasing the outside width too.

    Anyway, I will never buy a carbon fiber wheel, much less pay $1800 for a pair. I prefer the security of a hook bead and everyone isn't running tubeless ready or UST tires either. In fact, most tires I see shopping on the Interweb aren't. I sincerely doubt straight sided rims will be taking over anytime soon; if ever. The UST standard requires a hook beaded rim. Do you think that will be changed?

  64. #64
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    Wow, I can give some real-time updates here.

    Tried to mount some Schwalbe Furious Freds on a hook-based Chinese carbon rim wheelset for almost 2 weeks. No go.

    Just bought the aforementioned $1800 hookless Specialised Roval Control SL 29s, and BINGO - mounted without soap suds immediately.

    Can't speak to burping yet, but at least in terms of mounting they've been great. I wouldn't be so quick to discount the SLs frankly.

  65. #65
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    Bead hook-less rims, are they the future?

    Quote Originally Posted by phlegm View Post
    Wow, I can give some real-time updates here.

    Tried to mount some Schwalbe Furious Freds on a hook-based Chinese carbon rim wheelset for almost 2 weeks. No go.

    Just bought the aforementioned $1800 hookless Specialised Roval Control SL 29s, and BINGO - mounted without soap suds immediately.

    Can't speak to burping yet, but at least in terms of mounting they've been great. I wouldn't be so quick to discount the SLs frankly.
    I fail to see how a straight sided rim makes it easier to mount a tire than a hook beaded one. But, you bring up a related point, these tubeless tires are too difficult to mount/dismount. It was a ***** to mount my tubeless ready tires on my Shimano and Mavic rims. I hope I can deal with that when I get a flat on the trail. Maybe that's where some design effort should go.

  66. #66
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    Quote Originally Posted by MikeDee View Post
    Whatever... Isn't this whole thing a solution to a non problem?
    Actually, it's an intelligent solution to several issues. It allows a larger internal width without a weight penalty, a stronger rim design, and a cheaper manufacturing option. Win, win, win.

    Quote Originally Posted by MikeDee View Post
    The OP was about Roval (Specialized) carbon wheels, which a Bicycling Magazine article I just read says cost $1800 a pair and was about making the sidewalls stronger (probably makes it easier for them to make a CF rim, truth be known). You can make the wall stronger by increasing the outside width too.
    Yes, the rim can be made stronger by increasing the outside width. But this comes at a weight penalty. I feel like a broken record, here...

    Quote Originally Posted by MikeDee View Post
    , I will never buy a carbon fiber wheel, much less pay $1800 for a pair.
    I fail to see how this is germane to the topic.

    Quote Originally Posted by MikeDee View Post
    I prefer the security of a hook bead and everyone isn't running tubeless ready or UST tires either.
    Did I not address this already? Why am I wasting my time?

    Quote Originally Posted by MikeDee View Post
    In fact, most tires I see shopping on the Interweb aren't.
    Most MTB tires currently for sale may not be tubeless ready or UST, but ALL high-end MTB tires(with the exception of downhill tires) are. Your point has no relevance.

    Quote Originally Posted by MikeDee View Post
    I sincerely doubt straight sided rims will be taking over anytime soon; if ever. The UST standard requires a hook beaded rim. Do you think that will be changed?
    Again, I said give it two years and the hookless rim will be the most common type among high-end MTB rims. The UST standard is irrelevant. Most rim and tire manufacturers do not bother with the certification.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  67. #67
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    Quote Originally Posted by MikeDee View Post
    I fail to see how a straight sided rim makes it easier to mount a tire than a hook beaded one.
    It doesn't.

    Quote Originally Posted by MikeDee View Post
    But, you bring up a related point, these tubeless tires are too difficult to mount/dismount. It was a ***** to mount my tubeless ready tires on my Shimano and Mavic rims. I hope I can deal with that when I get a flat on the trail. Maybe that's where some design effort should go.
    The difficulty in a tire's mounting/dismounting has very little to do with the design of the tire, unless the bead is severely undersized (which is the case with WTB's TCS tires). The majority of the problems lie with improper technique. In some cases, a shallow rim drop-center is also to blame.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  68. #68
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    I can't figure out who is "right" or "wrong" here.

    Suspect my recent issues are certainly germane:

    1. Chinese hooked rim. Stan's tape. Schwalbe Furious Freds. Don't mount.
    2. Specialized hookless rim (Roval Control Sl). Spesh tape. Same Schwalbe Furious Freds. Not just same type of tire - the exact same tires. Mount instantly.

    Tires, and my "technique" remain constant. Rim shape (and edge) only variable (aside from tape).

    Explain.

  69. #69
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    Bead hook-less rims, are they the future?

    Quote Originally Posted by bholwell View Post
    Actually, it's an intelligent solution to several issues. It allows a larger internal width without a weight penalty, a stronger rim design, and a cheaper manufacturing option. Win, win, win.



    Yes, the rim can be made stronger by increasing the outside width. But this comes at a weight penalty. I feel like a broken record, here...



    I fail to see how this is germane to the topic.



    Did I not address this already? Why am I wasting my time?



    Most MTB tires currently for sale may not be tubeless ready or UST, but ALL high-end MTB tires(with the exception of downhill tires) are. Your point has no relevance.



    Again, I said give it two years and the hookless rim will be the most common type among high-end MTB rims. The UST standard is irrelevant. Most rim and tire manufacturers do not bother with the certification.
    Certification is another thing, but all engineered tubeless systems rely on a hook beaded interface. Being an engineer in the industry, you should reflect on the fact that, for the dubious savings of few grams and manufacturing ease, you're willing to sacrifice a key safety feature and violate a principal design element of the only accepted standard in the industry that governs this interface. Two words: product liability.

  70. #70
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    Quote Originally Posted by MikeDee View Post
    Certification is another thing, but all engineered tubeless systems rely on a hook beaded interface. Being an engineer in the industry, you should reflect on the fact that, for the dubious savings of few grams and manufacturing ease, you're willing to sacrifice a key safety feature and violate a principal design element of the only accepted standard in the industry that governs this interface. Two words: product liability.
    Incorrect. UST included the bead hook for backwards compatibility with non-tubeless tires. With a correctly designed tubeless tire, the bead will never touch the bead hook. This is why Spesh rovals and Enve tubeless rims have dropped the hook. If you look at any mature tubeless design, such as cars or motorcycles, you'll see there is no hook despite significantly higher side loads.

  71. #71
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    This has grown quite tiresome, so this will be my last post in this thread.

    Quote Originally Posted by MikeDee View Post
    Certification is another thing, but all engineered tubeless systems rely on a hook beaded interface.
    Actually ALL engineered tubeless systems, with the exception of bicycle, do NOT have a bead hook on the rim. LT/Passenger, motorcycle, ATV, industrial, etc. Tire manufacturers perform testing to ensure their tires' beads and carcasses are strong enough, plus a factor of safety. When an engineer with over five years of experience in the industry tells you that MTB tire beads are now strong enough to be able to eliminate the bead hook on the rim, why do you not believe him?

    Quote Originally Posted by MikeDee View Post
    Being an engineer in the industry, you should reflect on the fact that, for the dubious savings of few grams and manufacturing ease, you're willing to sacrifice a key safety feature and violate a principal design element of the only accepted standard in the industry that governs this interface. Two words: product liability.
    I'm no longer in the bicycle industry. And the bead hook is far from a "key safety feature" of the rim. I can guarantee you that Specialized and ENVE have conducted burst testing using their hookless rims and tires of various manufacturers. And what they've found, in addition to the ability of the tires to be inflated to the maximum inflation pressure called out on the tire's sidewall plus a factor of safety without blowing off of the rim, is that the presence of the bead hook does little to nothing in retaining the bead of the tire when set up tubeless.

    And the UST standard only governs the dimensions of the rim, and states some basic parameters the tires must meet. The rim manufacturer must use the rim dimensions and pay a fee to Mavic in order to use the UST logo and call their rims "UST" compliant. The UST standard says nothing with regards to tire bead dimensions or how strong the beads must be; this is the responsibility of the tire manufacturer. There is no governing body.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  72. #72
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    There are a couple of keyboard commandos here that need to both apologize, and do a bit of reading on ERTRO , and Mavic's control of UST.
    bhowell is a wealth of knowledge whose input is highly regarded. Your trollish posts are not cool..

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  73. #73
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    Bead hook-less rims, are they the future?

    Quote Originally Posted by Flyin_W View Post
    There are a couple of keyboard commandos here that need to both apologize, and do a bit of reading on ERTRO , and Mavic's control of UST.
    bhowell is a wealth of knowledge whose input is highly regarded. Your trollish posts are not cool..

    ...sent by dixie cup/string
    Bholwell is advocating making making it less safe for all of us by eliminating the rim hook, which has served for 100 years to keep a bike tire on the rim for little to no gain. Too bad you drank the Kool Aid.

  74. #74
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    Name:  Atomik AM-MOD Cross Section.jpg
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Size:  30.8 KBI have been watching this thread and would like to add to the argument for hooks. I would also appreciate if BHolwell responded and address our design...his expertise as a tire engineer is valuable to this thread, but regarding hooks on a rim, there may be other reasons to consider.

    If you take a look at our Mod Hook ( atomikcarbon.com | High Performance Carbon Fiber Mountain Bike Components) design. You will notice that it is different that the typical Hook design. Based on the testing we did in our lab, our Mod Hook Design is 30% stronger for IMPACT than a hookless design.

    First our wall thickness is 3.5mm...most hook less designs are not as wide, although quite a few manufacturers are adopting this wider/thicker wall thickness for obvious reasons. Our "hook" is short and quite thick, this reduces the leverage effect that a thinner and longer hook would create. As a matter of fact, out first Gen 1 version had a thinner and longer hook and we had a few breakages, we went back and redesigned and have not had any problems.

    The second thing you will notice is that the top is "flat" and 4.5mm wide. Think of hitting a nail on the point or the head of the nail. A hook less rim with the rounded profile means that it is much easier to compromise the carbon where it is most likely to be impacted. With our 4.5mm wide profile, the impact is distributed over a larger and more substantial area.

    Third, we have guys like Thomas Vanderham and Rowan Sorrell testing our rims before we bring to the marketplace. The Mod Hook was developed as a AM/ENDURO rim....in other words, very strong. What we are told is that guys of this caliber will INCREASE the pressures of their tire to 40+ PSI when descending rocky trails and trails with a lot of jumps. As you know these hookless rims work great in a low pressure situation.

    We have also decided to add a 12K weave to our Mod Hook AM/Enduro rim to make the impact even stronger....of course no carbon rim is impervious to damage, but we have created a super strong product.

    We do have a hookless rim that we call out Trail rim....for situations where the strength is not required.

    Wayne Lee
    Atomik Carbon

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    Quote Originally Posted by Atomik Carbon View Post
    Based on the testing we did in our lab, our Mod Hook Design is 30% stronger for IMPACT than a hookless design.
    Can you please detail the specific considerations behind your 30% stronger claim? Does it compare designs using the same total volume of carbon overall or within the wall region? Is it stronger because it simply has thicker and heavier walls, or do you claim the improvement is due to a fundamental design difference? Do you argue that the hook directly increases impact strength of the rim? If, so, can you please enumerate that argument?

    For reference, the hook is the wall region which is not directly supported by the seat and is only supported by wall shear.

    Also, do you agree with bholwell that the hook is a significant stress riser in the design?

    Kind regards.
    80 Mongoose, Z-rims
    84 GT, Araya 7x, Uni Seat, Potts Mod, Holeshot
    92 Rockhopper
    98 Stumpy M2, Z2 BAM
    12 SL-R
    14 Ripley

  76. #76
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    [QUOTE=ca_rider;11756503]Can you please detail the specific considerations behind your 30% stronger claim? Does it compare designs using the same total volume of carbon overall or within the wall region? Is it stronger because it simply has thicker and heavier walls, or do you claim the improvement is due to a fundamental design difference? Do you argue that the hook directly increases impact strength of the rim? If, so, can you please enumerate that argument?

    For reference, the hook is the wall region which is not directly supported by the seat and is only supported by wall shear.

    Also, do you agree with bholwell that the hook is a significant stress riser in the design?

    Kind regards.[/QUOTE


    Take another look at our design. See the slope under the hook?? See how thick the hook is and how short it is ?? This reduces the stress riser considerably.

    We tested our Mod Hook Against our 3.5MM hook less design. We kept dropping weights on both rims till they cracked.....in every case, our mod hook required more weight to develop a crack...on average 30% more weight.

    This rim is not for everyone. Fast and aggressive guys that ride rock gardens and jumps INCREASE tire pressure. The Mod Hook is an additional protection.

    There are a lot of hook less rims with 2.5MM wall thickness with a radius end. It takes a lot less pressure/impact to break that rims than it does our Mod Hook. It is really simple....just more mass at the point of impact. With a flat profile...the impact load is distributed over a larger area. Again I use the example with a nail. Hit the point and see what happens, hit the flat end and the energy is over a larger area and there is minimal damage.

    Note...this has nothing to do with whether a hook is required to keep the tires on....it has more to do with additional impact strength.

    I look forward to your response and to B Holwells response as well.

    Take a look at the difference between a traditional hook and our Mod Hook.

    Best Regards,

    Wayne Lee
    Atomik Carbon


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    The is pretty funny reading back on. It's amazing how ****ing stupid and parinoid some are about hookless. I'll never go back to a hooked rim!

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