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  1. #1
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    Lefty: bearing reset every 50km?

    Hi there,

    I am the proud and happy owner of a 130mm carbon Lefty PBR, which makes me smile everytime i ride my Rize.
    However, since a couple of weeks it needs a bearing reset every 50km's or so.
    Now I know that the right thing to do is to ship it to Cannondale or 88+ and have it serviced, but unfortunately money is a bit tight, so I was wondering if there is something I can do myself (apart from resetting before every ride)
    I do all the maintenance on my bike myself and also have some experience with servicing a Talas, Bomber and Reba.
    So apart from the money my goal is to be able to do everything on my bike, however, the Lefty seems quite complicated and I have no idea what could be the cause of the the bearing reset issue.
    So my question is: Does anyone have an idea what is the problem with the fork (are the bearings or races broken?) and how I can fix it without spending 250 euros on it?

    By the way, I am from Rotterdam, the Netherlands, so a trip to Mendon is a bit to far

    Thanks in advance!

  2. #2
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    Quote Originally Posted by suravida
    Hi there,

    I am the proud and happy owner of a 130mm carbon Lefty PBR, which makes me smile everytime i ride my Rize.
    However, since a couple of weeks it needs a bearing reset every 50km's or so.
    Now I know that the right thing to do is to ship it to Cannondale or 88+ and have it serviced, but unfortunately money is a bit tight, so I was wondering if there is something I can do myself (apart from resetting before every ride)
    I do all the maintenance on my bike myself and also have some experience with servicing a Talas, Bomber and Reba.
    So apart from the money my goal is to be able to do everything on my bike, however, the Lefty seems quite complicated and I have no idea what could be the cause of the the bearing reset issue.
    So my question is: Does anyone have an idea what is the problem with the fork (are the bearings or races broken?) and how I can fix it without spending 250 euros on it?

    By the way, I am from Rotterdam, the Netherlands, so a trip to Mendon is a bit to far

    Thanks in advance!
    The only option besides having the bearing preload set properly is to use a thicker grease on the races.....and to adjust your fork with less sag....
    The needle bearings are sandwiched between the steel races.....the ones on the inside (4 ) are all different thicknesses and let's say, set in a unique sequence....
    You really need to know what you're doing or you can make things even worse....
    It's not like a traditional fork were when a bushing is worn one you just press it out and replace it with a new one in a few minutes.....
    "Common sense isn't always that common!"
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  3. #3
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    Mine is on its way back from its 4th trip to Cannondale for the same reason. This last time though was because the inner races were migrating. Awesome suspension when it is working though.
    I'm not sure if there is something wrong with the structure on mine for it to go wrong so many times. Mine is a 2009 FWIW.
    I am having them put the OPI lower in this time so at least the inner races can't migrate now becasue they will be attached to the lower unlike with the old 2 piece lower.

  4. #4
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    Every 50km??

    That is crazy!
    My Cannondale Lefty keeps failing....

  5. #5
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    Like cdalemaniac said, bearing preload is the best answer. Thicker grease will likely make the fork do odd things that you won't smile about.

    For my $? If times are tight, just reset it and deal. I mean, what's it take? 3 minutes?

    The higher the preload, the stiffer the action gets, so if it makes you smile as it sits, run it like you stole it
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  6. #6
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    How do I change the bearing preload? Putting more pressure in the fork?
    And whats could be the reason for this issue? Worn bearings?

    And you are right, a bearing reset is a very quick and simple procedure, so I'll keep on doing that until my moneytree blossoms again ;-)
    I would like to fix it before june, when I plan to make some seriously long trips in the Alps, I dont fancy taking a BB tool with me then....

  7. #7
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    Quote Originally Posted by suravida
    How do I change the bearing preload? Putting more pressure in the fork?
    And whats could be the reason for this issue? Worn bearings?.
    When it's torn down for a rebuild, you can change it.

    It's like setting the gap on spark plugs, it's not something that "happens" it's something that is, and can be changed till it fit's the parameters set by the manufacturer.

    Also, it's not an "issue" really, it's part of any needle bearing device, be it a MTB fork, or a large industrial machine. Preload changes are simply a function of fine tuning

    It's the inner races job to create it. They are available in thickness differences of 1/1000th. Most forks can be built up with perhaps even 4 different thicknesses resulting in a super stiff acting fork, to a super smooth one.

    The trick is to get it in the range that feels good, without allowing migration to happen too quickly.

    The problem is, certain riders and certain conditions, or combos of the two, make the benchmark that they are built to, not be quite acceptable to that individuals needs. Other factors include too much or too little grease, races and bearings getting more polished with use, a bit of extra plastic flashing that was on the bearing cages when new, going away etc etc etc.

    In your case, I'm guessing that by simply bumping two of the races up a thousandth, the problem will be much reduced.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  8. #8
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    Thanks! Thats a clear answer. I think I'll just bring it to 88+ then, hear they set up your fork perfectly.
    By the way, somewehere on this forum I read that there is a kit for the first series PBR that can reduce diving, I just cant find it anymore... Do you know anything about it, and do you think it's necessary?

  9. #9
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    Quote Originally Posted by suravida
    Thanks! Thats a clear answer. I think I'll just bring it to 88+ then, hear they set up your fork perfectly.
    By the way, somewehere on this forum I read that there is a kit for the first series PBR that can reduce diving, I just cant find it anymore... Do you know anything about it, and do you think it's necessary?
    Dude...88+ charges way too much...it would be cheaper to send it to Mendon even if you're in Europe....
    A friend of mine paid almost 300.- euros and that was only a regular tune up with seal replacement on a Lefty Max spv.....
    That's like $360.- .... ridiculous!
    "Common sense isn't always that common!"
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  10. #10
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    My lefty 29er has the same problem. The needle bearings wear at the top of the stroke of the fork. I solved this problem by assembling my top-cap and c-clips in a different configuration. The top of the dampener has a 1 inch diameter disk with a groove in it. This groove is where you put the two half-moon shaped c-clips. If you set the c-clips on top of this disk, it extends the fork out by about 5 millimeters. You have to assemble the rest of the top-cap and lockout lever differently to make it work. Since I did this, I have had no stiction or bearing migration at all.

  11. #11
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    Quote Originally Posted by jcooper@fusd1.org
    My lefty 29er has the same problem. The needle bearings wear at the top of the stroke of the fork. I solved this problem by assembling my top-cap and c-clips in a different configuration. The top of the dampener has a 1 inch diameter disk with a groove in it. This groove is where you put the two half-moon shaped c-clips. If you set the c-clips on top of this disk, it extends the fork out by about 5 millimeters. You have to assemble the rest of the top-cap and lockout lever differently to make it work. Since I did this, I have had no stiction or bearing migration at all.
    No disrespect, but what you've done has no impact on anything related to nearing migration. It's akin to saying that longer travel forks don't have migration. You simply lengthened the fork a smidge, that's it.

    Also, the bearings don't wear any more at one portion than another. The top end of the races will get a bit more polished due to more action happening there, than deeper in the stroke.

    I can't see as what you did, causing any danger, but it isn't taking care of anything, mechanically speaking, and while you may have a different experience with your migration for some inexplicable reason, all needle bearings migrate, period.

    Not being a jerk, please understand. What your saying makes as much sense as saying your car is faster with the windows down, the two factors aren't even related.....
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  12. #12
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    The bearings do wear most at the top of the stroke. The wear on the needle bearings causes stiction (maybe it isn't stiction, but it gets hung up) where the bearings are worn. Since most of the telescoping action is done in the first inch of the stroke, this is worn more.

    You can put 150psi in your fork and it will have enough pressure to push past this "stiction". But then you might as well have a rigid fork.

    When you extend the fork out by 5 to 8 mm, the top of the stroke is rolling on "new" needles. Your fork will go way longer without having to reset the bearings, and you can run the fork at 100psi.

  13. #13
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    Quote Originally Posted by jcooper@fusd1.org
    The bearings do wear most at the top of the stroke. The wear on the needle bearings causes stiction (maybe it isn't stiction, but it gets hung up) where the bearings are worn. Since most of the telescoping action is done in the first inch of the stroke, this is worn more.

    You can put 150psi in your fork and it will have enough pressure to push past this "stiction". But then you might as well have a rigid fork.

    When you extend the fork out by 5 to 8 mm, the top of the stroke is rolling on "new" needles. Your fork will go way longer without having to reset the bearings, and you can run the fork at 100psi.
    Um, okay. How many of these do you work on? Just curious, as no one I've ever spoken to @ Cannonale, has ever mentioned this, and I'm fairly certain that the other folks with experience around here haven't either.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  14. #14
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    Quote Originally Posted by MendonCycleSmith
    Um, okay. How many of these do you work on? Just curious, as no one I've ever spoken to @ Cannonale, has ever mentioned this, and I'm fairly certain that the other folks with experience around here haven't either.
    I guess what he wants to say is that if you extend it a bit the needle bearings touch unworn race surface, resulting in a bit more preload overall....
    Makes sense, but is only a band-aid fix like the other options that were mentioned and to be honest I don't believe that a few mm of "new" race surface will make a huge difference overall....
    "Common sense isn't always that common!"
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  15. #15
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    I don't work on any lefty other than my own and you can take that however you want Seriously though. I have been taking notes on this fork daily for a year now. It is a 2008 carbon 29er.

    In November 2009 the fork had seals changed and bearings/races replaced by Cannondale as routine for a fork ridden hard for a year and a half. Immediately, the fork felt short. This is where I first heard about bearing migration and the procedure on how to "reset" the fork by removing the top cap and extending the fork out all the way. It takes some banging around for this. By June 2010, I sent it back to Cannondale because it wouldn't make it a ride without the fork extending all the way out (about a half inch too short). They rebuilt it and nearly $300 later, the fork worked perfect... for about a month.

    This is when I had the idea that a machine shop could make those half-moon c-clips, only so it holds the top of the dampener in place, but offsets the dampener about a centimeter down into the fork leg. This would increase the axle to crown, but would use a unused part of the bearing race. I mean, the fork can telescope out two more inches when you reset the bearings.

    Like a puzzle, I played around with the top of the dampener and the c-clips until I came up with "my" solution. The only problem was how to prevent the fork from telescoping out the remaining 2 inches. This could cause disaster.

    I used the top-most 10mm hex nut (the one that holds the lockout lever on to the top of the dampener) to keep the fork from telescoping out.

    The only down side to this is that the lockout lever really shouldn't be used. In other words, don't use the lockout lever.

    Now, I think that is a smart thing to do.

    I have been riding it this way for 6 months without a hitch. I finally did have to reset the bearings, once.

    I see how this solution could be particular to my fork. Machining elongated c-clips could also be a cheap way to safely lengthen your race-to-crown.

  16. #16
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    Quote Originally Posted by jcooper@fusd1.org
    In November 2009 the fork had seals changed and bearings/races replaced by Cannondale as routine for a fork ridden hard for a year and a half. Immediately, the fork felt short. This is where I first heard about bearing migration and the procedure on how to "reset" the fork by removing the top cap and extending the fork out all the way. It takes some banging around for this. .
    The owners manual that came with my 2006 Lefty Max detailed the reset procedure.

    I've "reset" the bearings once, not because I needed to, but just to find out how it was done.

    I've maintained an ave. ~ 120 mi +/ week/ 8 months out of the year, with mileage the rest of season more weather dependent.

    I don't know if ~ 25,000 mi in 5 yrs constitutes "riding hard", but it's only had it's bearings reset once and is still working as good as new.

  17. #17
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    Quote Originally Posted by jcooper@fusd1.org
    I don't work on any lefty other than my own and you can take that however you want Seriously though. I have been taking notes on this fork daily for a year now. It is a 2008 carbon 29er.

    In November 2009 the fork had seals changed and bearings/races replaced by Cannondale as routine for a fork ridden hard for a year and a half. Immediately, the fork felt short. This is where I first heard about bearing migration and the procedure on how to "reset" the fork by removing the top cap and extending the fork out all the way. It takes some banging around for this. By June 2010, I sent it back to Cannondale because it wouldn't make it a ride without the fork extending all the way out (about a half inch too short). They rebuilt it and nearly $300 later, the fork worked perfect... for about a month.

    This is when I had the idea that a machine shop could make those half-moon c-clips, only so it holds the top of the dampener in place, but offsets the dampener about a centimeter down into the fork leg. This would increase the axle to crown, but would use a unused part of the bearing race. I mean, the fork can telescope out two more inches when you reset the bearings.

    Like a puzzle, I played around with the top of the dampener and the c-clips until I came up with "my" solution. The only problem was how to prevent the fork from telescoping out the remaining 2 inches. This could cause disaster.

    I used the top-most 10mm hex nut (the one that holds the lockout lever on to the top of the dampener) to keep the fork from telescoping out.

    The only down side to this is that the lockout lever really shouldn't be used. In other words, don't use the lockout lever.

    Now, I think that is a smart thing to do.

    I have been riding it this way for 6 months without a hitch. I finally did have to reset the bearings, once.

    I see how this solution could be particular to my fork. Machining elongated c-clips could also be a cheap way to safely lengthen your race-to-crown.
    That is really "Mac Gyverish" of you
    Can you post pics when you have the time?
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  18. #18
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    Here are some pictures of what I am talking about.
    Attached Thumbnails Attached Thumbnails Lefty: bearing reset every 50km?-c-clips-different-position-5.5mm-difference.jpg  

    Lefty: bearing reset every 50km?-configuration-increases-atoc-5mm.jpg  

    Lefty: bearing reset every 50km?-normal-configuration.jpg  


  19. #19
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    The middle and bottom pictures show the clips in offset position and normal position, respectively. This is what I did to reduce the frequency of resetting my bearings. I'm tired of spending money on this fork and waiting a month for the fork to get back to me, just to have the thing start acting up again a month later.

    If you don't mind not having a lockout lever and rebound knob, you can offset this more using other types of spacers.

  20. #20
    All Lefty's, all the time Moderator
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    Quote Originally Posted by cdalemaniac
    I guess what he wants to say is that if you extend it a bit the needle bearings touch unworn race surface, resulting in a bit more preload overall....
    Makes sense, but is only a band-aid fix like the other options that were mentioned and to be honest I don't believe that a few mm of "new" race surface will make a huge difference overall....
    Even if it were a "fix" it would only work till the wear he suggests moved upward. And since they don't wear in any appreciable sense, it's a moot point. Also, moving it up a few mm's would only create an impact on perhaps two or so of the 22 needle bearings per strip, which won't have any difference at all. It also wouldn't increase bearing preload, but for the sake of argument, if it did, any amount of sag once you get on the bike, would put you right back in the "worn" area he's referring to. Also, by his thought process, longer travel forks wouldn't migrate by nature of being longer, as that's all he's affecting.

    I'm not saying he isn't experiencing some sort of change, and I can't parse out the cause with so little background info, but being around these things many times a day as I am, what he's saying is having an impact has no function in mechanics of the thing.

    To impact reset intervals, you need to increase bearing preload along it's whole length, since as soon as it gets into the travel, it's away from the area he impacted. And, sadly, no, the race and bearing aren't worn, (thus he isn't increasing preload at all) they polish in, but you can mic a used race against a new one, and it's consistent it's whole length, every time.

    My only guess is that since he has a few more mm's, he has more time cushion before getting as migrated.

    I'll also add, nothing against Cannondale but I hear this comment often, I sent it back for X, and it wasn't addressed. Why that is, I can't say, and I won't cast aspersions, but if I have a customer tell me migration happens too fast for them, it's a no brainer, and I have a customer without the problem once they get it back. Perhaps because I'm dealing one on one and know the complaint when I see the fork, and take the obvious solution steps, as opposed to just saying, "we checked it when we serviced it, and it's within correct parameters", might be the difference.....

    Please understand jcooper@fusd1.org, I'm not trying to be a jerk, or say you're wrong, but you're suggesting something that makes no sense (if it did, Cannondale would have addressed it YEARS ago, trust me they're always playing around and tweaking things), and the one thing I try to do on this board, more than anything else, is to politely correct bad or false information, before someone damages their fork, or themselves, as both, get rather costly.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  21. #21
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    I did adjust the pressure in the fork to increase the sag, and you are correct that it returns to the same spot anyway. However, when I hit a bump, it rebounds past (by a couple of needle bearings) where the wear is. In effect, it resets my bearings every time my front wheel leaves the ground. I'm not pretending to be an expert on this. Actually, it is the complete opposite.

    What cannondale needs is better costumer support. If I would have brought my fork in to you, I believe the problem would be fixed the first time. You understand these forks enough to ask costumers the right questions and communicate that to Cannondale.

    By the way, I would normally be riding now, but I had hernia surgery 5 days ago and am stuck at my house.

    I look forward to talking to you more about this, I have a lot of questions about mounting my lefty on a Jet 9. That can wait.

  22. #22
    All Lefty's, all the time Moderator
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    Quote Originally Posted by jcooper@fusd1.org
    I did adjust the pressure in the fork to increase the sag, and you are correct that it returns to the same spot anyway. However, when I hit a bump, it rebounds past (by a couple of needle bearings) where the wear is. In effect, it resets my bearings every time my front wheel leaves the ground. I'm not pretending to be an expert on this. Actually, it is the complete opposite.

    What cannondale needs is better costumer support. If I would have brought my fork in to you, I believe the problem would be fixed the first time. You understand these forks enough to ask costumers the right questions and communicate that to Cannondale.

    By the way, I would normally be riding now, but I had hernia surgery 5 days ago and am stuck at my house.

    I look forward to talking to you more about this, I have a lot of questions about mounting my lefty on a Jet 9. That can wait.
    Okay, as I said, I'm not attacking you, I'm just not seeing how this has any impact. So, I did some riding, beer ingesting, and thinking, and still came up blank.

    Spoke with Cannondale this AM, to the guy who pretty much created the whole program for Headshocks and Leftys, and knows the forks better than anyone.

    First off, he stands by my assertion that you are not impacting preload at all. He also used the word scary, just FYI.

    His thought is, and I like this, the since the whole system is unsupported from dropping downward, that you are, in a sense, creating a situation where the fork is auto resetting itself, a little bit with each cycle. Neat in concept, but unsafe, and in the long run, not a practice to continue, after all, they design a simple reset procedure for a reason, so you can do it, easily, and without much hassle. If it were me, I'd put it back to proper position, now.

    If you want the bearing preload adjusted, that will make a difference in how long between resets, but will also slightly change how buttery the fork feels. Not a horrible thing, but just so's you knows.....

    And just for the record, since you seem to think that I'd send stuff into Cannondale from my shop, nope, I service all stuff here, hence a pretty deep understanding of the mechanics at play.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  23. #23
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    I have a 130 PBR aswell and I rebuilt it sometime ago Im pretty sure I saw a clip at my LBS's manual for the fork that was holding all the for inner bearing races in place.

    My fork was missig this clip and the LBS said it was an upgrade for older forks (but didnt have it in stock - doh!

    Pehaps your fork is also missig the clip and you can upgrade with that??

    It dont lock the races but makes it impossible for one race to move without the other races moving.

    I guess Mendon can add some more info about this??

    /Fredde

  24. #24
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    Quote Originally Posted by fredde_nu
    I guess Mendon can add some more info about this??

    /Fredde
    Yeah, not relevant. The race clip keeps them from moving, which is a separate issue from bearing migration. Your shop was correct, older forks may not have it, many newer forks don't need it, and it isn't essential to them. You need inner races with holes for said clip, to install one.

    Many of the newer forks don't have them, due to the race ways now being cut in a way that captures the inners, keeping them from moving downward, yours is such a fork. It doesn't need one, and your races won't even accept one, just FYI....

    His will definitely have one, and even if it didn't, it wouldn't be causing hastened migration....
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  25. #25
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    Quote Originally Posted by MendonCycleSmith
    Yeah, not relevant. The race clip keeps them from moving, which is a separate issue from bearing migration. Your shop was correct, older forks may not have it, many newer forks don't need it, and it isn't essential to them. You need inner races with holes for said clip, to install one.

    Many of the newer forks don't have them, due to the race ways now being cut in a way that captures the inners, keeping them from moving downward, yours is such a fork. It doesn't need one, and your races won't even accept one, just FYI....

    His will definitely have one, and even if it didn't, it wouldn't be causing hastened migration....
    Yes I mixed it up, only my outer-races have those cut-outs on the edges not the inner-ones. Sorry about confusing.

    /Fredde

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