New Chumba F5

Discussion in 'The Pub' started by Mudman, Jan 13, 2008.

  1. Mudman

    Mudman Mr. Angry

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    yes indeed. My goal is to have 7 bikes. So I can ride a different one every day. :lol:
    Nope the photos don't do much for the color. But I have an idea :)

    how much is your arm and leg worth? ;)

    I'd still love the F5 in ano black and gloss black graphics!
     
  2. Rob

    Rob Active Member

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    They don't have the separate compression ring that sets the bearing preload. It's built into the top skirt of the headset. The problem with that is that it can rock back and forth when a lot of force is put on the bars.

    I have one installed in my Titus right now that I would let you ride if you like. Everything is perfectly installed, headtube reamed and faced, inner edges rounded and clean, everything lubed correctly, torqued to specs, etc.

    You'll feel it when you are going down tight switchbacks under braking, and when descending technical sections.

    I'm not the only one who feels this way either, check out other MTB forums and ask around. The Service Manager at the shop I work at has experienced the same problem with CK headsets on higher travel bikes.

    I'm going to try out the Cane Creek 110.

    :beer:
     
  3. alank

    alank New Member

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    .....

    Not clear - what is rocking back and forth?
     
  4. Rob

    Rob Active Member

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    The top bearing cover.

    [​IMG]
     
  5. Collette

    Collette New Member

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    So you want 365 different bikes then? :bang::lol:
     
  6. Mudman

    Mudman Mr. Angry

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    if I could then yeah!
     
  7. alank

    alank New Member

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    ..

    Okay, but my question is how does having a separate compression ring affect bearing preload versus the Chris King design in a way that would cause this rocking? Its not a big deal though - maybe I'll try your bike out - we should hook up for a ride.
     
  8. Rob

    Rob Active Member

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    A split compression ring will maintain even and permanent adjustment, no matter how much side load is put on the top cup.

    Because the compression ring on the CK headset's are built into the top cup when heavy loads are put on the bars it can cause movement and not give you a perfect 100% area of contact between the compression ring and the angular contact area of the top bearing.

    This same thing happens when you install a CK headset on a bike that has Cantilever brakes on the front and has the hanger built into one of the headset spacers. Once you have it all installed and pull the front brakes you can actually see a difference in the amount of gap between the top cup and the upper bearing from front to back. And this is with a hanger with a locking bolt. I had a CK headset installed on my Surly LHT with canti's in front. I'd get the same noise/clunk I get on my El Guapo when I sprinted and pulled hard on the bars. I switched over to a Cane Creek HS that had a split compression ring and it immediately fixed the problem.

    Not trying to bash on CK or anything, I'm just relaying my experience.
     
  9. RacinJason

    RacinJason Banned

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    Chris King is still the best

    Well Rob, you have a point. The CK head set cap and race is somewhat floating on an O ring. They do this so that the tolerances allow for many types and brands of forks. (Great Observation)

    1 1/8 in. to some companies can fluctuate. As you will notice building many bikes, some forks are a tight fit in the cap/race. Some are not. They found a sweet spot.
    That o ring allows a slight movement. This is why they give you a Teflon sleeve. This lets it move a small amount and not make noise.

    The amount of movement is so slight, if any, that when adjusted properly it is unnoticeable.

    The race on the crown and the cap are designed to fit tight into the inner race on the cartridge bearing.
    It should not slip, ever.

    Many of the people who have had failures with CK head sets are people misusing them. If you run any head set loose, it will be destroyed in a matter of hours, depending on the type of riding you are doing.

    Sometimes when a fork bushing is sticky or dry, it can seize and can damage head sets. That applies to any brand and style.




     
  10. Rob

    Rob Active Member

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    Yeah I tried it with and without the plastic sleeve and no dice. I think it just makes a lot of sense to use a split compression ring and then a top cap. This rules out any problem at all.

    I think this is just as pretty as a CK anyways.

    [​IMG]
     
  11. RacinJason

    RacinJason Banned

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    I have used the Hope, Cane Creek, FSA ,Tange and many others.
    Call me and I can tell you abour all of them.
     
  12. Do Work

    Do Work Eddie would go...

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    Anyone out there have the answer to the million dollar question...anyone...hellllooooo...:?:
     
  13. Pugz

    Pugz Fat guy in a little coat

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    I wanna know the price, those are some really sweet looking bikes.
     
  14. Do Work

    Do Work Eddie would go...

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    Bump....:?:
     
  15. RacinJason

    RacinJason Banned

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    Around $4200.00 - $4500.00 depending on the build.
     
  16. project_d

    project_d Steve Peat Wannabe

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    Those are pretty sweet lookin':clap:
     
  17. Steven Jackson

    Steven Jackson My loop, my rules!

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    Duzz that bike cum with a box of tampons?
     
  18. RacinJason

    RacinJason Banned

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    Ha Ha

    No but we are installing a swiveling beer holder. :beer:


     
  19. Dino Brown

    Dino Brown Sir Smack-Alot

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    Swiveling beer holder? :eek:
    Looks like you just sold three bikes: Brewmaster, JasonMason and Katonk!

    :beer:
     

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