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  1. #1
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    New question here. New Lefty Rider needs help ???

    Hello, I am new to this forum and also a first time Cannondale lefty owner. I recently purchased a used Prophet and will be going on my first ride with it tomorrow a.m. so your replies will greatly be appreciated. Here is my questionn...
    Should the lefty action be buttery smooth when holding the front brake and compressing and releasing the lefty? There seems to be some minor grinding or rubbing sensation when I compress the shock. It is very faint but my analness seems to pick it up. Please let me know your thoughts about this... Thanks in advance, Roger

    ps. It is a lefty Max SPV non-carbon

  2. #2
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    Should be as buttery either way. I had the same thing about the slight grinding sensation, but i took to see what the shop thought of it and they said it was nothing.

  3. #3
    The Martian
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    My lefty (brand new....4 rides max) has a very slight (but noticeable) grinding feeling when being compressed while stationary. It always has, though it is more noticeable now that I have the air pressure much lower to account for my weight.

    You may want to check the pressure and set the sag, which you should definitely do anyway to set the bike up for you. Otherwise I probably wouldn't worry about it too much.

  4. #4
    All Lefty's, all the time Moderator
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    You're feeling the needle baerings rolling. Nothing to be concerned about. If you didn't feel it at all, it would indicate a rather light bearing preload, which would lead to more rapid bearing migration. It's a fine line. Just ride it, and have fun
    This is a Pugs not some carbon wannabee pretzel wagon!!

    - FrostyStruthers



    www.mendoncyclesmith.com

  5. #5
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    feeling bearings rolling?

    MendonCycleSmith-

    What do you mean by "indicate a rather light bearing preload, which would lead to more rapid bearing migration"?

    I have been searching the forum this morning because I just had my needle bearings reset yesterday on my 2007 Speed Carbon SL at a shop for the first time ever. My fork felt like butter beforehand, absolutely smooth. Afterwards I pushed down on the fork and I felt a regular roughness more at the top end of the compression esp. if I go slowly and apply less force. (I asked the mechanic about it and he said he didn't have time to look at it right now that's all, no other explanation).

    After reading this post -- yes, it's like bearings rolling! Roughly though, like they are big bearings bump bump bumping along. Why though would I feel the bearings rolling? Shouldn't bearings be smooth if all's ok? I've never felt this even with my new fork. I do weight 115 and have the lightest cartridge inside but I didn't change the cartridge. This doesn't make sense to me. Can you help me understand and let me know if I should do anything to my fork?

    Thanks!!

    p.s. My fork came apart while riding due to the locktite service bulletin/recall issue last year. C'dale replaced it but it's still left me with a bit of nervousness about riding a fork that's less than perfect.

  6. #6
    All Lefty's, all the time Moderator
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    Quote Originally Posted by rushrider
    What do you mean by "indicate a rather light bearing preload, which would lead to more rapid bearing migration"?

    My fork felt like butter beforehand, absolutely smooth. Afterwards I pushed down on the fork and I felt a regular roughness more at the top end of the compression esp. if I go slowly and apply less force.

    Why though would I feel the bearings rolling? Shouldn't bearings be smooth if all's ok? I've never felt this even with my new fork. I do weight 115 and have the lightest cartridge inside

    p.s. My fork came apart while riding due to the locktite service bulletin/recall issue last year. C'dale replaced it but it's still left me with a bit of nervousness about riding a fork that's less than perfect.
    Okay, bearing preload is (loosely) the amount of pressure required to make the forks sliding shell (no spring or damper invloved) move. It is controlled by the thickness of the inner races. The slider has four flats, each has a long thin steel strip (race), then a needle bearing strip, then another race. The outer race remains constant in it's thickness, regardless of the fork. The inners are often different from each other by a thousandth or more in thickness. By making the inners thinner, the preload goes down, and the fork moves more easily. Thicker? Requires more pressure to make it move. The range it should be in is about a pound to 1.5 lbs of pressure to compress the slider. If it's too light, then the bearings have less pressure on them, and they can be "pulled from the sandwich" more easily. Think of it as a piece of ham in between 2 slices of bread. Pull it out, when it's sitting on a plate? No problem. Now put your hand on top of the sandwich and push down. Try to remove the ham. Much tougher now. You hand is increasing bearing preload. Or in this case, ham preload Bearing migration occurs naturally, as the outer leg gets slowly stuffed down over the inner, as the bearing inbetween is not capable of stopping said movement, but with proper preload, it's a manageable thing.

    Why your fork felt perfect before, and now has bearing feel in it, I can't say. Possible causes include light amount of grease, water intrusion, or tight bearing preload. I say, if your boots in tact, no tears, and the fork is less than a year old, ride it. If you notice it on the trail, I'll be very surprised. If it really bugs you, or is so apparent on the trail that it drive you to drink, get the preload lightened. I do it regularly, and it's easily accomplished during a normal service. The cartridge's only difference between heaviest to lightest is the negative spring. The rate of that, will have no impact on bearing feel.

    To say that your fork is less than perfect due to the recall situation, is akin to saying that since you made a PB+J sandwich, but forget the jelly, realized it when you sat down to eat, and took one bite before going back and putting it on, makes your sandwich an imperfect thing. It's Loctite, that was forgotten, not a badly made piece, some part that was not included, or the thing is warped. It's perfect, trust me. And at this point, whatever isn't exactly what you like about it, can be tuned, not made more perfect.
    This is a Pugs not some carbon wannabee pretzel wagon!!

    - FrostyStruthers



    www.mendoncyclesmith.com

  7. #7
    LA CHÈVRE
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    Ham preload!

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  8. #8
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    Thank you very much, I understand it better now. You suggest that light amount of grease might be a culprit. All of the work done to the fork was done up top. No lifting of boot/grease added. Would adding grease help? The fork boot is intact.

    Oh no, I didn't mean that my fork was less than perfect simply because of the recall, I just meant that after the experience I went through - that is, riding along on a fork that made some strange noises/bumps and then having it come apart a few minutes later I'm a little leary of riding any fork that makes strange noises/bumps because I worry about something bad happening.

  9. #9
    All Lefty's, all the time Moderator
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    Quote Originally Posted by rushrider
    All of the work done to the fork was done up top. No lifting of boot/grease added. Would adding grease help?
    Anywhere you put grease at the bottom, will not get it where the "possible" issue is. Get some trail time on it. If it still feels like poo, deal with it then.

    Like that Ham bit huh Dan? I had food on the brain, even though it was just after breakfast. I often use food metaphors for bike stuff in the mornings, odd.....
    This is a Pugs not some carbon wannabee pretzel wagon!!

    - FrostyStruthers



    www.mendoncyclesmith.com

  10. #10
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    Craig i suggest you should write a manual /book!
    I can only think of the title: Lefty-Sandwich Anatomy.
    As for the inside materials it's your ride!
    The best exambles i read until now.!
    Now my friends will understand better the answer in the ususal question where's the other part of the fork?

    How i didn't think of it until now (considering that i am a speechtherapist)

    Craig you should start writing books for kids and i will take care the publishing part.....

    Rock on

  11. #11
    LA CHÈVRE
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    Quote Originally Posted by MendonCycleSmith
    Like that Ham bit huh Dan? I had food on the brain, even though it was just after breakfast. I often use food metaphors for bike stuff in the mornings, odd.....
    I read it just before I had my breakfast so that might explain my reaction. But now it's almost lunch time, getting hungry again, time for my Lefty sandwich.

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  12. #12
    All Lefty's, all the time Moderator
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    Ha! Spiros, what I need to do now is comb all my posts on various things, and compile it. That way I can save on typing Wonder how a ham sandwich analogy translates into Greek????

    Dan, darn it, now I'm hungry again, all this talk of ham and whatnot. Guess it's lunch time
    This is a Pugs not some carbon wannabee pretzel wagon!!

    - FrostyStruthers



    www.mendoncyclesmith.com

  13. #13
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    ham sandwich analogy= analogia zambon sto sandouits

    But i told you don't worry about that i wiil take care the publishing-translation staff.

    You will just have to sign the copies as a famous writer

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