Advertise on Bikeforums.net



User Tag List

Results 1 to 4 of 4
  1. #1
    Senior Member
    Join Date
    Jul 2008
    My Bikes
    Brompton, Dahon Vitesse D5
    Posts
    1,834
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)

    Shimano Dura Ace BB 7700 / 7703 differences

    I've seen images and descriptions of the 109mm spindle length BB 7700 and it appears to be semi-sealed, i.e. it's an updated version of a cup & cone BB that can be fully dismantled and requires careful cup/locknut adjustment. The cups are connected and sealed with a black plastic middle shell.
    I've also seen images of what may be a BB 7703, 118.5mm spindle length, which appears to be a fully-sealed cartridge unit. So I'm wondering if this difference was, for some unknown reason, connected to spindle length, or that there were two different designs pertaining to different years and that the 109mm version also came out as a fully-sealed cartridge BB?

  2. #2
    Senior Member
    Join Date
    Aug 2005
    Location
    Pittsburgh, PA
    My Bikes
    '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
    Posts
    26,174
    Mentioned
    13 Post(s)
    Tagged
    0 Thread(s)
    For the 7700-series (9-speed Dura Ace) Octalink bottom brackets the 109 length was for a double crank and was expected to be used for competative racing where very low weight and seal drag was considered important. The 118 mm spindle was for the triple crank and it was assumed low maintenance was more important than the minor weight and adjustability penalty.

    For the Ultegra 6500 and 105 5500 9-speed Octalink bottom brackets, both the 109 mm double and 118 mm triple spindles came as fully sealed cartridge units.
    Last edited by HillRider; 05-24-12 at 05:25 PM.

  3. #3
    A little North of Hell
    Join Date
    Mar 2006
    Posts
    4,410
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    [SIGPIC][/SIGPIC]
    XXXI

  4. #4
    Senior Member
    Join Date
    Jul 2008
    My Bikes
    Brompton, Dahon Vitesse D5
    Posts
    1,834
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Aha, thanks for your help.

Posting Permissions

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