Advertise on Bikeforums.net



User Tag List

Results 1 to 5 of 5
  1. #1
    Junior Member
    Join Date
    Feb 2010
    Posts
    11
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    FSA SL-K Light Crank Question.

    I have a FSA SL-K Light crank with 170 crank arms and 52-39 chain rings. I came across a FSA SL-K Light compact crank with 172 crank arms and 50-34 chain rings. The crank is no good but the crank arms and chain rings are still good! Can I switch out the crank arms and chain rings to my FSA crank? Would everything match up?

  2. #2
    Certified Bike Brat Burton's Avatar
    Join Date
    Jan 2011
    Location
    Montreal, Quebec
    Posts
    4,203
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    What do you mean by 'the crank is no good'? Its a two piece crank. The chain rings are replacable and so are the external bearings but thats it.

  3. #3
    Senior Member
    Join Date
    Apr 2010
    Location
    SoCal
    My Bikes
    Roubaix SL4 Expert
    Posts
    2,156
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Standard cranks (53/39) typically use a different bolt circle diameter (BCD) than compact cranks (50/34) so you probably can't swap chainrings. The drive side crank arm is integrated with the chainrings so you can't just swap crank arms and make a franken-crank out of the 50/34 parts.

  4. #4
    Certified Bike Brat Burton's Avatar
    Join Date
    Jan 2011
    Location
    Montreal, Quebec
    Posts
    4,203
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dunbar View Post
    Standard cranks (53/39) typically use a different bolt circle diameter (BCD) than compact cranks (50/34) so you probably can't swap chainrings. The drive side crank arm is integrated with the chainrings so you can't just swap crank arms and make a franken-crank out of the 50/34 parts.
    In this particular case both the standard and compact versions have a BCD of 110mm and use a BB30 interface. So he CAN swap out the chainrings, but the crank arms are out of the question. Unless he just means the bearings are done - but then - there's nothing to swap over so I'm left with a big ????

  5. #5
    Junior Member
    Join Date
    Feb 2010
    Posts
    11
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks for everyone's response! Was looking on a listing on E-Bay that had 50-34 chainrings and wanted to switch them with my standard 52-39 chainrings. Now I know the BCD is different (110mm-130mm) I will sell the standard crank and look for a compact crank! My bikes are older and do not have the option to use a BB30.

Posting Permissions

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