Advertise on Bikeforums.net



User Tag List

Results 1 to 9 of 9
  1. #1
    Senior Member
    Join Date
    Jul 2005
    Location
    Quebec, Canada
    My Bikes
    2010 Cannondale RT2 Tandem
    Posts
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    How to remove C'dale eccentric bottom bracket?

    I want to remove the eccentric shell to clean and regrease everything before reassembly of the tandem, its a 2008 RT3 cannondale

    How do I remove the eccentric shell from the frame?

    The cranks are off, the eccentric turns freely, but I can't slide it on either side to remove it.

    do I have to unscrew the bearings from the eccentric first?

    Thank you!
    2010 Cannondale RT2
    2008 Cannondale RT3

  2. #2
    and HemiGirl! CapTandem's Avatar
    Join Date
    Jul 2008
    Location
    Olathe, KS (SW suburb of Kansas City)
    My Bikes
    2007 Cannondale Tandem; 2006 Specialized Roubaix; 1993 Specialized Allez Epic
    Posts
    24
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    My 2007 Cannondale Tandem has the "double-wedge" eccentric, which I am almost certain you will have.

    As designed by Cannondale, tightening the hex head cap screw, opposite the timing chain side, will tighten both wedges at the same time. A very secure design. The rub is when you want to loosen both wedges to adjust or remove the eccentric. The hex head cap screw is secured to the wedge with an internal "c" ring. Loosening the screw will push against both wedges to loosen the eccentric, as long as the "c" ring is in place.

    My experience was that the groove in the wedge for the internal "c" ring was easily "rounded" off, and once that happened, I could not get a "c" ring to stay in place for the hex head screw to push against. I was stuck and both wedges can be very difficult to loosen. I would suggest that you loosen the hex head screw and gently tap to remove the wedge on the timing chain side. Then gently tap the body of the eccentric toward the timing chain side. This is the best option that I know of.

    My solution was to go to Tandems East and purchase from Mel his modified "double-wedge" eccentric for the Cannondale. He was willing to refund part of my purchase price when I returned my old eccentric to him as a "core" for him to "remanufacture". That was four years ago, and he may have modified his policy.

    There are other upgrade eccentrics that you can purchase for more money, but I found this to be the best bang for my buck.

    Good luck, and hope to see you on the road!
    Hope to see y'all on the road!

    2007 Cannondale tandem w/front & rear disc brakes
    2006 Specialized Roubaix carbon fiber single
    1993 Specialized Allez Epic carbon fiber single

  3. #3
    Senior Member
    Join Date
    Jul 2005
    Location
    Quebec, Canada
    My Bikes
    2010 Cannondale RT2 Tandem
    Posts
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    That is what I want to do, both wedges are loose, eccentric turns freely, but the shell will not come out, do I have to remove the bearings first so it wil come out?
    should it just slide out of the timing chain side?


    Quote Originally Posted by CapTandem View Post
    My 2007 Cannondale Tandem has the "double-wedge" eccentric, which I am almost certain you will have.

    As designed by Cannondale, tightening the hex head cap screw, opposite the timing chain side, will tighten both wedges at the same time. A very secure design. The rub is when you want to loosen both wedges to adjust or remove the eccentric. The hex head cap screw is secured to the wedge with an internal "c" ring. Loosening the screw will push against both wedges to loosen the eccentric, as long as the "c" ring is in place.

    My experience was that the groove in the wedge for the internal "c" ring was easily "rounded" off, and once that happened, I could not get a "c" ring to stay in place for the hex head screw to push against. I was stuck and both wedges can be very difficult to loosen. I would suggest that you loosen the hex head screw and gently tap to remove the wedge on the timing chain side. Then gently tap the body of the eccentric toward the timing chain side. This is the best option that I know of.

    My solution was to go to Tandems East and purchase from Mel his modified "double-wedge" eccentric for the Cannondale. He was willing to refund part of my purchase price when I returned my old eccentric to him as a "core" for him to "remanufacture". That was four years ago, and he may have modified his policy.

    There are other upgrade eccentrics that you can purchase for more money, but I found this to be the best bang for my buck.

    Good luck, and hope to see you on the road!
    Edit, ok, got it, removed the BB cups, a few taps on the eccentric shell with a rubber mallet and it came out.
    Interesting to see the weight of a M/S bare cannondale frame, heavier than I expected
    Last edited by Eddie50; 09-17-14 at 02:20 PM.
    2010 Cannondale RT2
    2008 Cannondale RT3

  4. #4
    and HemiGirl! CapTandem's Avatar
    Join Date
    Jul 2008
    Location
    Olathe, KS (SW suburb of Kansas City)
    My Bikes
    2007 Cannondale Tandem; 2006 Specialized Roubaix; 1993 Specialized Allez Epic
    Posts
    24
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Just got home from work (midnight local time). Glad to read that you got the eccentric out. Sounds like your home free. Have fun!
    Hope to see y'all on the road!

    2007 Cannondale tandem w/front & rear disc brakes
    2006 Specialized Roubaix carbon fiber single
    1993 Specialized Allez Epic carbon fiber single

  5. #5
    Gear Combo Guru Chris_W's Avatar
    Join Date
    May 2007
    Location
    Switzerland
    My Bikes
    Spec' Tarmac (road), Spec' Secteur Disc (commuter & tourer), Salsa Mamasita (MTB), CoMo Speedster (tandem), Surly Big Dummy (cargo), Airnimal (folder), a train pass, and NO car :)
    Posts
    2,073
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I work in a shop that sells Cannondales and a couple of other bike brands. We joke that the big rubber mallet in the workshop is only for Cannondale bikes because we seem to need to use it to do any major task on any Cannondale frame (removing Hollowgram crank axles, Lefty fork tubes, eccentric BBs, etc., etc.), but rarely have to use it on any other bikes. Therefore, the general rule of thumb to remove something from a Cannondale is to give it good bash.

  6. #6
    Senior Member
    Join Date
    Jul 2005
    Location
    Quebec, Canada
    My Bikes
    2010 Cannondale RT2 Tandem
    Posts
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks for the tips everyone!

    would anybody know the size of the circlip and washer that holds the wedge bolt? I have to change them and put new ones, did not find specs on the cannondale manual.
    2010 Cannondale RT2
    2008 Cannondale RT3

  7. #7
    and HemiGirl! CapTandem's Avatar
    Join Date
    Jul 2008
    Location
    Olathe, KS (SW suburb of Kansas City)
    My Bikes
    2007 Cannondale Tandem; 2006 Specialized Roubaix; 1993 Specialized Allez Epic
    Posts
    24
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I found a match at my local Ace Hardware store, back with the exotic nuts and bolts in the pull out drawers. It was listed on the pull out drawer, as I recall, as an internal "C" ring clip, it was the smallest one in the drawer.

    I gave up on the circlip in the wedge and bought a modified eccentric, as I described above. Before I gave up, I purchased a replacement circlip from Cannondale through my local bike shop because I could not find a spec for replacement. Turned out to be the same one available at the hardware store.
    Hope to see y'all on the road!

    2007 Cannondale tandem w/front & rear disc brakes
    2006 Specialized Roubaix carbon fiber single
    1993 Specialized Allez Epic carbon fiber single

  8. #8
    Member
    Join Date
    Dec 2007
    Posts
    40
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Eddie50 View Post
    I want to remove the eccentric shell to clean and regrease everything before reassembly of the tandem, its a 2008 RT3 cannondale

    How do I remove the eccentric shell from the frame?

    The cranks are off, the eccentric turns freely, but I can't slide it on either side to remove it.

    do I have to unscrew the bearings from the eccentric first?

    Thank you!
    http://www.tandemseast.com/parts/brackets.html...Hi Eddie50 get replacement EBB modified by them . swap your existing Eccentric shell with theirs .Dont waste your time like I did ,ordered parts from Cannondale .the grooves that the clips rest in is too shallow poor design .

  9. #9
    Senior Member zonatandem's Avatar
    Join Date
    Dec 2003
    Location
    Tucson, AZ
    My Bikes
    ariZona carbon fiber tandem & single
    Posts
    10,048
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    The 'dale setup is not exactly the best/easiest available.
    Leave up to Mel K at Tandems East to come up with a better mousetrap!
    Peal on~
    Rudy and Kay/zonatandem

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •