Results 1 to 3 of 3
  1. #1
    RoadBikeReview Member
    Reputation:
    Join Date
    Mar 2007
    Posts
    7

    spacers w/ISIS bottom bracket

    Hi there, hoping for a quick answer so I can go riding before dark, so I'll keep this short.

    Got a new entry level road bike at a great deal, but I'm on my own mechanically for it. When in the smallest chain ring, the chain rubbed on the large ring when using the three smallest cogs in the rear. So I got a spacer. I take it apart only to discover there's already a spacer. Can I safely use a second spacer? Shell width is 68mm. Spindle length is 108 mm. Both pre-existing and new spacers are 2.5 mm thick.

    The bottom bracket is a Chin Haur (?) Isis Drive. If its of any importance, I'm 225 lbs and pack lots of leg power.

    Thanks in advance!

    -Yann

  2. #2
    RoadBikeReview Member
    Reputation:
    Join Date
    Feb 2004
    Posts
    10,126

    chainline...

    Rather than add another spacer, which would indicate a significant frame misalignment, check the chainline. The tip of a tooth on the big ring should be 47-48mm from the centerline of the seat tube. The best way to check this is to measure from the side of the tube with a precision scale, then add 1/2 of the ST diameter to the measurement. If the chainline is 47mm or larger, adding another spacer is not a good idea.

    I would also check the width of the BB shell to see if it's the proper 68mm width.

    If you have a compact 50/34 crank, then you may have to live with the problem, or install a 113mm bottom bracket which would add 2.5mm to each side.

  3. #3
    RoadBikeReview Member
    Reputation:
    Join Date
    Mar 2007
    Posts
    7
    Thank you for the prompt reply C-40. I'll put it back together for now so I can go riding and then I'll make the measurements you suggested.

Posting Permissions

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

2015 LIGHTS SHOOTOUT

Hot Deals See All Hot Deals >>

Interbike Featured Booths

Check out the hottest road bike products from these brands!



















See All Interbike Coverage - Click Here »


Latest RoadBike Articles


Latest Videos

RoadbikeReview on Facebook