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  1. #1
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    Idea! Why pawl hubs fail

    The tl:dr theory: because poor machining causes the pawls to not engage at the same time. Full drivetrain force goes through a single pawl and it breaks.

    Last night I was clicking an XTR hub absentmindedly in my hands when I noticed that with each engagement of the freehub, there wasn't a unified click. Turning the freehub slowly, I could get one, then two, then the third pawl to engage. The rotational distance was small but it didn't take much skill to do. We'll call this being out of phase.

    Trying this with other hubs, I found the same out of phase condition:

    Shimano XT 8000
    Shimano Dura Ace 9000 x 2
    Bitex road
    DT Swiss 370
    WI CLD+, a premium hub!

    The Bitex was by far the worst. A "click" on this hub at a gentle finger turning speed was clearly a series of clicks, whereas on the others the speed had to be very low to notice.

    While the window of catching a pawl out of phase is small, given enough tries under normal riding conditions, there will be a time when the rider puts down the power and fewer than the full number of pawls are engaged - possibly even just one! It would even be possible to calculate the probability if the out of phase angle were known.

    This would cause all the force of the drivetrain to go through one pawl, and that force would be off-center as well. How many times have we seen something like this?

    Why pawl hubs fail-freehub1.jpg

    It looks like the freehub got pushed into the drive ring, and this is a common failure on cheap hubs. You'll see similar pictures in Novatec, Koozer, and BHS hub threads. This probably isn't a flexy axle - axle stiffness is a function of material and thickness, and there are strict limits on these due to bearing id and through axle od.

    How about this, where a pawl chipped? All force going through one point and it failed
    .
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    For a perfectly in-phase pawl engagement, some precise machining needs to happen in multiple places - The free hub body and the holes drilled for the pawls, the pawls themselves in multiple dimensions, and the drive ring (at least; there may be others). I think this is the biggest reason why cheaper hubs fail faster than more expensive hubs where more attention has been paid to the machining precision and part fitment, such as I9 or WI. But I was still able to get a WI to click out of phase.

    This may be a reason why the DT style Star Ratchet is so reliable. It is easier to control the precision of the locking surfaces on the teeth, and there is no tolerance stacking that I can see. Of the three examples I own, I am unable to get them to partially engage.

    I'm interested to know if the owners of other high quality pawl hubs are able to get them to engage out of phase.

  2. #2
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    Good post. That last pic is EXACTLY what happened to my cheapo factory spec Novatec. Rendering it useless!

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    Quote Originally Posted by Schulze View Post
    I'm interested to know if the owners of other high quality pawl hubs are able to get them to engage out of phase.
    I have never actually tried to see if my I-9's do this 'outta phase' thing, but I think not. As you prolly already know, the I-9's have 6 pawls with 3 engaging at all times, followed by the next 3 pawls as the first 3 disengage.

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    I recently noticed this when building up a new set of wheels. I am using novatec hubs and was interested if I could maybe get some offset pawls (shorter ones) to increase the poe of the hub so I was testing out the engagement. If I am very precise there are two distinct engagement points where the pawls are out of phase. I would guess it's just one of the four pawls that's slightly out. I would think this would be very unlikely to get it happening when riding but photos above tell a different story (though is it only one pawl that's been chipped?).

    I also have a Hope pro2 evo which I couldn't get out of phase engagement on

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    I agree that this is likely the major cause of freehub bodies being gouged by the ratchet ring. For what its worth, I notice this issue is much less prevalent with hubs that are driven by only two pawls instead of three, such as Hope hubs or SRAM X0 or 900. It also helps that the pawls, springs and ratchet teeth are oversized by comparison.

  6. #6
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    As a somewhat counterpoint but not completely, the out of phase effect is meant in some cases as an effective increase of points of engagement. This is a compromise however since it caters to and relies on the user to be a less-than-peak force user. A heavy duty user would clearly stress the system to the limit shown. I have personally been using the style pictured for over 10 yrs of xc racing and commuting without problem. Of course that includes keeping the mechanism lubricated and cleaned regularly as well as being a smooth and paced rider.
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    Never had this issue with any hub I've owned including my current 120 POE Novatec. My hub is quite similar to the i9 posted above. it features six double-toothed pawls and 60 engagement teeth for a lightning-quick three degrees between engagement. The pawls of the hub are slightly offset so that only three can engage at a time, leaving the other three standing at the ready. Each pawl has two teeth to help eliminate slip.

    Most of the issues with Novatec hubs are related to the hub end cap coming loose, because the factory didn't apply any thread locker and most riders don't bother to check their hubs when they get their bikes/hubs.
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  8. #8
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    I think that's the pawls creeping down the ratchet ring unevenly for whatever reason. Grease buildup or loose springs.

    I don't know if it's really out of phase. It seems when torque is applied, the teeth fully engage and bottom out, going into phase.

    I think axle flex kills most pawl hubs.

  9. #9
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    The only pawl hubs I've killed were Mavic Crossmax hubs. I kept them cleaned and well-lubed because I had to take them apart every few weeks to keep them running.

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    There's too many variables amongst too many manufacturers to say that any one thing causes all pawl hub failures IMO.

    I've owned 4-5 Bitex hubs (went all in one year) and began having problems with all of them. I've broken more axles than I can remember, had exploded bearings, gouged freehubs to the point that the cassette breaks, and big marks where the freehub is contacting the drive ring like in your picture, etc.

    I've not had any issues with pawls being out of phase though, and not chipped any pawls. I swapped in steel axles for the ones that they were available for, and replaced all freehubs with the steel version. Still had a bearing fail in a 5 week old freehub last summer.

    These are not the only hubs I've had issues with, but they are clearly just not up to the task. Safe to say I'm done with those, most have been replaced and the rest will soon be.
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  11. #11
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    Some people ruin everything short of a DT or king. Are you one of those?

    I'm easy on hubs. Bitex do well for *most* people, but not hub ruiners. It's by no means beefy.

  12. #12
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    The only hub to ever fail on me out on the trail, requiring a walk-of-shame out, was a Chris King. It didn't freewheel freely after attempting to pedal up a steep rock that was about 5' high, stalling out, and ejecting. Let the bike roll back, and then heard a crunch when I tried to mount the bike with it moving, and cranks held still by my foot (RD's cage bottomed against the underside of chainstay). Pulled it apart, saw that helical spines on the alloy freehub were gouged. Didn't do anything but clean and lube and reassembled, and it worked fine after that. Video evidence: vimeo.com/35545233

    The hub that cost me the most in maintenance related failures, was the industry 9 enduro. I lost a XX cassette on it since it got stuck on its freehub. Wanted to take it off since the alloy ring folded a little on me to make the lowest 2 gears unusable (heard the alloy cogs were replaceable). Over $300 unsalvagable... tolerances too tight and gouging would lock the cassettes on them, I guess.

    I found myself super annoyed by loosely-held freehubs, like the DT 350, which the weight of the cassette cases everything inside to yard sale. Tired of the Stan's end caps getting cocked on the drop-outs too... ironically, they say it helps with maintenance.

    I rather have something that just works without needing any attention. I've become skeptical of precision engineered things that requires a super controlled environment to operate as expected. Just seem like pricey headaches to me. I suppose I didn't really have a reason to join the "overcompensating for something" camp, other than curiosity and an appreciation for engineering, considering I didn't really have any complaint with Formula hubs other than they lacked PoE. I currently deal with pedaling in chunk by just shifting up into a higher gear (32x36, my 2nd gear, is probably the easiest I'd use for tech).

  13. #13
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    Quote Originally Posted by One Pivot View Post
    Some people ruin everything short of a DT or king. Are you one of those?
    Maybe... My friends would say Yes, so would the guys at my LBS, I just say I'm more enthusiastic than most.
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  14. #14
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    Quote Originally Posted by Varaxis View Post
    I rather have something that just works without needing any attention.

    For me that's been DT, minimal attention anyway. Their star ratchet design is brilliant imo.
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    I've ruined the DT before. The good part is that it's stupid easy to replace. That was probably a combination of axle-flexing with QR axles back in the day, which combined with starting an effort (putting down power) meant that only certain teeth were partially engaged and they subsequently snapped. 99.9% of the time it's a stupid-simple way to deliver power and is very reliable for high torque applications. CK takes the same concept to the next level, but loses the simplicity of the DT system.

    I snapped many an older XT.

    Strangely, the Hope mechs are holding up well for me, 5+ years on one and around 3 on another. Easy to service and just seem to keep going, despite the traditional design.
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  16. #16
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    Quote Originally Posted by Schulze View Post
    The tl:dr theory: because poor machining causes the pawls to not engage at the same time. Full drivetrain force goes through a single pawl and it breaks.

    Last night I was clicking an XTR hub absentmindedly in my hands when I noticed that with each engagement of the freehub, there wasn't a unified click. Turning the freehub slowly, I could get one, then two, then the third pawl to engage. The rotational distance was small but it didn't take much skill to do. We'll call this being out of phase.

    Trying this with other hubs, I found the same out of phase condition:

    Shimano XT 8000
    Shimano Dura Ace 9000 x 2
    Bitex road
    DT Swiss 370
    WI CLD+, a premium hub!

    The Bitex was by far the worst. A "click" on this hub at a gentle finger turning speed was clearly a series of clicks, whereas on the others the speed had to be very low to notice.

    While the window of catching a pawl out of phase is small, given enough tries under normal riding conditions, there will be a time when the rider puts down the power and fewer than the full number of pawls are engaged - possibly even just one! It would even be possible to calculate the probability if the out of phase angle were known.

    This would cause all the force of the drivetrain to go through one pawl, and that force would be off-center as well. How many times have we seen something like this?

    Click image for larger version. 

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    It looks like the freehub got pushed into the drive ring, and this is a common failure on cheap hubs. You'll see similar pictures in Novatec, Koozer, and BHS hub threads. This probably isn't a flexy axle - axle stiffness is a function of material and thickness, and there are strict limits on these due to bearing id and through axle od.

    How about this, where a pawl chipped? All force going through one point and it failed
    .
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    For a perfectly in-phase pawl engagement, some precise machining needs to happen in multiple places - The free hub body and the holes drilled for the pawls, the pawls themselves in multiple dimensions, and the drive ring (at least; there may be others). I think this is the biggest reason why cheaper hubs fail faster than more expensive hubs where more attention has been paid to the machining precision and part fitment, such as I9 or WI. But I was still able to get a WI to click out of phase.

    This may be a reason why the DT style Star Ratchet is so reliable. It is easier to control the precision of the locking surfaces on the teeth, and there is no tolerance stacking that I can see. Of the three examples I own, I am unable to get them to partially engage.

    I'm interested to know if the owners of other high quality pawl hubs are able to get them to engage out of phase.
    Agreed. I returned a set of Dura Ace wheels for this exact reason. If you spun them by hand you could feel the tick tick of the paws out of phase. On the road they would catch only 1 paw and skip violently under power. Even my i9 hubs have a imperceptible amount of out of phase. Not enough to ever catch a paw though.

    Quote Originally Posted by GuitsBoy View Post
    I agree that this is likely the major cause of freehub bodies being gouged by the ratchet ring. For what its worth, I notice this issue is much less prevalent with hubs that are driven by only two pawls instead of three, such as Hope hubs or SRAM X0 or 900. It also helps that the pawls, springs and ratchet teeth are oversized by comparison.
    Freehub bodies being gouged by the ratchet ring has to do with bearing preload/tolerances and axle flex. The paws don't effect it.

    Quote Originally Posted by J.B. Weld View Post
    For me that's been DT, minimal attention anyway. Their star ratchet design is brilliant imo.
    Dt swiss hubs are best of the best, but the 54 rings are suspect. I destroyed a set over sever years. The smaller teeth started to chip and deform.
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    Quote Originally Posted by alexbn921 View Post
    Freehub bodies being gouged by the ratchet ring has to do with bearing preload/tolerances and axle flex. The paws don't effect it.
    If you only have two out of three pawls engaged, that is a significant source of axle flex and bearing runout. Axle flex alone does not explain why a freehub body would make contact with the ratchet ring. The hub shell bearing and inner freehub bearing are right next to eachother, and the axle flex would move both in unison. No contact. But if you have uneven pawl engagement, and sufficient play in the bearings, that easily explains pushing the freehub body into the ratchet teeth.

  18. #18
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    Quote Originally Posted by GuitsBoy View Post
    If you only have two out of three pawls engaged, that is a significant source of axle flex and bearing runout. Axle flex alone does not explain why a freehub body would make contact with the ratchet ring. The hub shell bearing and inner freehub bearing are right next to eachother, and the axle flex would move both in unison. No contact. But if you have uneven pawl engagement, and sufficient play in the bearings, that easily explains pushing the freehub body into the ratchet teeth.
    If the paw are in or out of step they will have almost no effect on the ring to freehub body clearance compared to hitting a rock at speed or casing a jump.
    The scoring comes from impacts that flex the axle decreasing the clearance. Also bearings that are bad or out of spec will reducing the clearance under high impact loads.

    I have seen scoring on almost all paw hubs and I know that not everyone has out of phase paws.

    For example in this video. There is no way you can impart 1/10 of the force pedaling.
    https://www.youtube.com/watch?v=U8YEMP9rdkI
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  19. #19
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    Quote Originally Posted by alexbn921 View Post
    If the paw are in or out of step they will have almost no effect on the ring to freehub body clearance compared to hitting a rock at speed or casing a jump.
    The scoring comes from impacts that flex the axle decreasing the clearance. Also bearings that are bad or out of spec will reducing the clearance under high impact loads.

    I have seen scoring on almost all paw hubs and I know that not everyone has out of phase paws.

    For example in this video. There is no way you can impart 1/10 of the force pedaling.
    https://www.youtube.com/watch?v=U8YEMP9rdkI
    I completely disagree.

    I'm not saying that axle flex is not significant during high impact events. I'm saying that both the hub and the freehub follow the axle deflection. There's little or no force pulling the hub in one direction and the freehub in the opposite direction. If axle deflection were purely the cause for gouged freehubs, you'd see more substantial damage on the outside edge of the freehub. As the axle would bend, the outboard edge of the freehub body would be the first place to make contact with the ratchet ring, and therefore it would have the deepest gouges.

    But we dont typically see that. Instead the gouges are pretty uniform in depth across the entire freehub body. Thats an indication that the entire freehub body is being pushed off axis, and not that its being tilted or skewed. To me, that means uneven pawl engagement, and not axle flex.

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    Quote Originally Posted by GuitsBoy View Post
    I completely disagree.

    I'm not saying that axle flex is not significant during high impact events. I'm saying that both the hub and the freehub follow the axle deflection. There's little or no force pulling the hub in one direction and the freehub in the opposite direction. If axle deflection were purely the cause for gouged freehubs, you'd see more substantial damage on the outside edge of the freehub. As the axle would bend, the outboard edge of the freehub body would be the first place to make contact with the ratchet ring, and therefore it would have the deepest gouges.

    But we dont typically see that. Instead the gouges are pretty uniform in depth across the entire freehub body. Thats an indication that the entire freehub body is being pushed off axis, and not that its being tilted or skewed. To me, that means uneven pawl engagement, and not axle flex.
    It's an interesting idea. Since the same paws are the always the ones engaging first wouldn't the direction of force rotation always be the same? I would expect to only see indents on one side of the freehub body if that was the case. I would also expect to see crisp single lines from the indents and we tend to see wider areas effected. We also see more indents then the total number of points on the ring.
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    Quote Originally Posted by alexbn921 View Post
    It's an interesting idea. Since the same paws are the always the ones engaging first wouldn't the direction of force rotation always be the same? I would expect to only see indents on one side of the freehub body if that was the case. I would also expect to see crisp single lines from the indents and we tend to see wider areas effected. We also see more indents then the total number of points on the ring.
    I'm not convinced that the slow to engage pawls are actually due to manufacturing tolerances. It could well be due purely to bearing runout or the tiny amount of play in between the axle and bearings. Gravity or chain tension could pull the freehub ever so slighly off center, causing some pawls to engage just fractionally earlier than the others. If you happen to crank at the exact moment only some pawls are engaged, boom, theres your problem. If the cassette and freehub happen to be oriented 180* out the other way, then maybe its the opposite pawls that are slow to engage.

    Higher quality hubs seem to have better tolerances all around. Tighter fitting axles. Better bearings, etc. That alone may be enough to largely mitigate the issue.

    I'm at work right now, but does anybody have a wheel with a freehub that exhibits the uneven pawl engagement? Maybe you could test if theres any difference with the wheel oriented vertically vs oriented horizontally? But even still, orienting it horizontally does not guarantee the freehub would be perfectly centered. Not really sure how to prove or disprove the theory.

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    Quote Originally Posted by GuitsBoy View Post
    Instead the gouges are pretty uniform in depth across the entire freehub body. Thats an indication that the entire freehub body is being pushed off axis, and not that its being tilted or skewed. To me, that means uneven pawl engagement, and not axle flex.
    I agree with this, and for the most part, the premise of the entire thread. I posted a much less well presented complaint about this problem several years ago, under my previous username, in an Easton hub thread when I was growing frustrated with my Easton M1 hubs. They were sold as high-end but were junk in the freehub department. Previously I had developed a similar opinion of Mavic rear hubs. I recognize there are certainly decent pawl hubs out there, but I now avoid them all. It's what led me to try Onyx hubs, the desire for a bombproof reliable means of engagement. All the other features were a bonus, and now I won't run anything that isn't silent.

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    One additional thing to add to the above discussion. Gouging on the freehub is repetitive and uniform, not random. That means the pawls must be engaged when the freehub is making contact with the ratchet ring. That's rare during high impact events like a jump, drop, rock, etc. If the pawls were not engaged, that means the ratchet ring of is traveling faster than the freehub, and that would result in "scrapes" against the freehub body, rather than defined and uniform gouges. Or so goes the theory, anyway.

    Also, just to clarify one thing alexbn921 mentioned, this is not dependent on offset pawls. It doesnt matter if the hub has 2, 4, 3 or 6 pawls. Pawls are always intended to have symmetry when driven, so either 2 or 3 will be engaged at any time. The discussion is about failure of one or more pawls to engage when they should, resulting in asymmetric engagement. Schulze the OP described it well, turn the cassette very very slowly and you can feel and hear each individual pawl engage, when in an ideal world it would be one synchronized "click".

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    Quote Originally Posted by Cleared2land View Post
    I have never actually tried to see if my I-9's do this 'outta phase' thing, but I think not. As you prolly already know, the I-9's have 6 pawls with 3 engaging at all times, followed by the next 3 pawls as the first 3 disengage.

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    Excellent photo! Yes I would be interested to know how your hubs click.

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    Quote Originally Posted by One Pivot View Post
    I think that's the pawls creeping down the ratchet ring unevenly for whatever reason. Grease buildup or loose springs.

    I don't know if it's really out of phase. It seems when torque is applied, the teeth fully engage and bottom out, going into phase.

    I think axle flex kills most pawl hubs.
    If one of x number of pawls engage before the rest, then bottoming out under torque would push the edges of the unengaged teeth farther away from engaging. It may even cause deformation and exacerbate the out of phase possibility.

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    Quote Originally Posted by Schulze View Post
    Excellent photo! Yes I would be interested to know how your hubs click.
    They click very well, thanks.

    I'm not sure that I understand what you mean by that question. They seem synchronized and not 'out of phase'.
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    Can you turn the freehub slowly and hear one or two of the pawls engage before the third?

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    Quote Originally Posted by Schulze View Post
    Can you turn the freehub slowly and hear one or two of the pawls engage before the third?
    yes. i warrantied a set of dura ace hubs for that exact reason.
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    Quote Originally Posted by One Pivot View Post

    I don't know if it's really out of phase. It seems when torque is applied, the teeth fully engage and bottom out, going into phase.

    I think axle flex kills most pawl hubs.
    I would tend to agree with this, not that the axle is flexing per say but the hub/freehub is not meshing well due to flex in the entire system.

    I'd put the most blame on the drive side bearing and ancillary factors of machining/engineering tolerances on the rest of the hub. Whenever I've blown up a hub it always originated with the drive side bearing. Obviously a broken pawl or ring drive ramp is going to wreak havoc but I've only run high end hubs for the last 20 years or so and haven't experienced that.. I've blown out the hub pawl pocket but the actual pawls remained intact.
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    Quote Originally Posted by Schulze View Post
    Can you turn the freehub slowly and hear one or two of the pawls engage before the third?
    That's what I thought that you meant. I tried this on both of my I-9 wheel sets (multiple times) and I can not distinguish any differential clicks in the pawl engagements. Even when moved very slowly, I am clearly able to hear a well-defined, simultaneous engagement of the 3 sets of engaging pawls. I am able to hear a crisp, single snap of engagement that demonstrates no ‘out of phase’ engagement.
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    Quote Originally Posted by Cleared2land View Post
    That's what I thought that you meant. I tried this on both of my I-9 wheel sets (multiple times) and I can not distinguish any differential clicks in the pawl engagements. Even when moved very slowly, I am clearly able to hear a well-defined, simultaneous engagement of the 3 sets of engaging pawls. I am able to hear a crisp, single snap of engagement that demonstrates no ‘out of phase’ engagement.
    With the cassette on the freehub, while pushing the cassette sideways to simulate chain tension, and moving from the outer teeth very, very slowly... can you hear very subtle variation of the pawls dropping out of sync? We're talking about a couple of thousandths of an inch. But with high end hubs, its probably much harder to do.

  32. #32
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    Quote Originally Posted by alexbn921 View Post
    yes. i warrantied a set of dura ace hubs for that exact reason.
    Smart move.

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    I can hear individual engagements on some I9 hubs if you turn them very very very slow.
    I have never broken a pawl on any hub. Although I buy new equipment almost every year. But I do have some wheels I've had for years with "prone to failure" freehubs and they aren't broken. I'm 170 pounds and can pedal very hard.

    I think most pawls break due to rapid high tq engagement. So from freewheeling to a rapid hard hit like an impact gun does. And also from worn bearings or any type of loading that causes the freehub to no longer be in line perfectly with the hub shell. There is one brand out there I'm pretty sure has this issue.

  34. #34
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    You are exactly right. I've seen this on most pawl hubs. Some hubs can handle only one or two pawl engagement if the shell material is durable enough to handle the force of one pawl and if the axle is big enough to limit the flex. White Industries uses a titanium freehub, therefore making the socket that the pawl sits in more durable. Hope uses a 17mm axle and heavy pawl springs.

    Ratchet hubs like Chris King and DT Swiss can potentially slip, but they drive all gears at once. Onyx drives all sprags at once even if one engages slightly before another.

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    Very good thread.

    I'm not a big masher, but some of the cheap hubs really need some TLC to keep them together. If you have bad lube, looseness, weak springs, wide fit tolerances, or shoddy assembly (bearing/drive ring not seated from factory), any one of those can explode a cheap hub (and all seem to be endemic to cheap hubs). Even the "good" hubs can be affected by bad lube or cold temperatures or a bad spring, though.

    About the pawls - in the case where only one or two (out of 3) engage, the axle and hub will deform relative to eachother, creating a larger gap on the side where the pawls engaged as the pawls push the ratchet ring and axle off center. If that gap is too large, the pawls have a huge leverage pushing the axle off center. The worse part about that is that the pawls are at a greater angle to the ratchet ring and then subjected to high shear forces as opposed to mostly compression forces. Kapow!

    And while King hubs are pretty awesome (I have some from 1993), they can get bad if the lube is no good (or it gets really cold). I never destroyed it, but I had to send it back for a factory overhaul.

    Loose drive ring. Not sure the mfr. (off '08 Iron Horse MkIII Comp) The ring seated (screwed in under pedal forces), which reduced the engagement between the pawls and the ring and the pawls were contacting near the edge, instead of across the entire pawl. The crooked forces cracked the hub and crushed it onto the axle.
    Why pawl hubs fail-100_3321.jpg

    Novatec fat hub. I check it frequently, but it still shows some distortion. It has made a few loud "clack!"s, but since I'm not Hercules, it still works.
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    The King is still in good shape. 2nd rim.
    Why pawl hubs fail-ckrearhub.jpg

    And I have an American Classic from 2007 on my 29er that's still doing well and might very well have the most miles on it. 3rd rim.
    (no pic)



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  36. #36
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    I’ve never had pawls fail in a hub.

    I have two sets of Chris King geared hubs that are >10 years old (slightly newer SS too), DT 240s 18/36/and 54t, Stan’s (Chosen) and others.

    All of them work flawlessly with minimal maintenance every year or two. I’ve munched Stan’s bearings and would not consider I9’s as they’ve had chronic bearing issues.



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    ^^^^ Do you use the CK hub lube tool? Regular service?
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  38. #38
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    Quote Originally Posted by *OneSpeed* View Post
    Maybe... My friends would say Yes, so would the guys at my LBS, I just say I'm more enthusiastic than most.
    Come on, just admit it, you're simply a HOE.
































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    Quote Originally Posted by MendonCycleSmith View Post
    Hard On Equipment.
    I'm not sure where the emphasis was intended, but if we're talking about a device, I already have more than enough offers in my spam folder.

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    Now I get it, the paws are hard on equipment.
    Latitude 61

  41. #41
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    Quote Originally Posted by Cleared2land View Post
    ^^^^ Do you use the CK hub lube tool? Regular service?
    I don’t use a hub lube tool or bearing removal tool. Every 12-18 months I remove the axle and drive shell, clean the ring drive, add CK ring drive lube as the docs specify. Clean the inner drive shell bearings and add a small amount of synthetic grease.

    If the (front or rear hub) outer bearings are not rolling smoothly, I remove the outer snap ring & black grease seal, clean the bearings and add a small amount of ring drive lube.
    【ツ】 eDub 【ツ】

  42. #42
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    I snapped pawls 3 at a time. Not just one. They are weak... dt swiss for me only.


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    Interesting read on the new I9 hubs. Seems they're embracing and leveraging flex and asymetric pawl engagement to their advantage.

    Under very low load and perfect alignment and zero flex, only one pawl would engage. As torque is applied, the freehub components would flex until a second pawl engages. Continue adding torque and a third engages, and so on.

    https://www.pinkbike.com/news/review...ydra-hubs.html

  44. #44
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    Debating on this issue right now as a boost wheel build is in progress. Looking at either DT 350 or a new I9 101 rear hub. Rachet or pawls?
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  45. #45
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    ^^^^ What's your end objective? Price point? POE?
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  46. #46
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    Quote Originally Posted by Cleared2land View Post
    I have never actually tried to see if my I-9's do this 'outta phase' thing, but I think not. As you prolly already know, the I-9's have 6 pawls with 3 engaging at all times, followed by the next 3 pawls as the first 3 disengage.

    Name:  Industry-Nine_2492 R.jpg
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    They can when the springs get old and soft or break with sloppy bearings, I found they still works fine with two Pawls engaged.
    Easy fix, I got a set of new springs good as new.

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    It sounds like I9's attack on this problem is to design the system to work with one pawl or eccentric loads. From the pinkbike comments:

    IndustryNineOfficial:" @tripleultrasuperboostplusplus: You are correct that the Hydra system does allow a small amount of eccentric rotation accommodated by flex. However, the amount of rotation is very small and that rotation essentially stops once the third pawl engages. The load is fully supported by the three pawls at this point and the materials in the drive ring, pawls, and FH body are not anywhere close to their yield point. In a traditional 3 pawl or 6 pawl phased MTB freehub, if you have three pawls engaged at the same time the load on the system is neutral. However, since there is constantly flex being introduced into the system when you are riding, it is fairly common for only a single pawl to engage in a symmetrical system. When this happens the FH is subject to large uncontrolled eccentric rotation which can cause premature bearing wear or in extreme cases, material deformation to the FH body. Our Torch MTN system was built to withstand these loads by utilizing an oversized drivering to reduce peak cantilever loads and a double row inner FH bearing with a higher load rating than most hubs on the market. However, the Hydra system eliminates these extreme stresses since the continuously phased pawls always allow the two trailing pawls to back up the initial pawl that has engaged limiting the system to a small amount of controlled flex.

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