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Compact Cranks

Steven FordSteven Ford
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Before I pull the trigger on this expense is everything look okay?

Shimano Ultegra Crankset 6750 Compact, 165 34/50

Shimano Ultegra Bottom Bracket BB-6700, BSC

Shimano Ultegra Cassette 6700 10 Speed, 12-25



In case it makes a difference I ride 650's

Comments

  • Gordon CherwoniakGordon Cherwoniak

    I don't know about the components but yes the 650's make a difference you will have a litte less top end gear ratio.  50-12 is 7.8 on a 650 and 8.4 on 700's.  What does this mean on a flat course with a tail wind and a kick a$$ FTP you might think about an 11 or perhaps an 11-23.  You could also consider the 11-26 depending on the races you do, but for all intense purposes the 12-25 will be fine.

    Go to Sheldon Brown's website (http://sheldonbrown.com/gears/

    You can see the gear ratio's for at 50-34 - 12-25.  This might not mean much but it will tell you where the holes in you cassette might be.  For example the 34-14 gear ratio is the same as 50-21 so a good time to shift in to the big ring.

    Read this page for an explanation from Sheldon:

    http://sheldonbrown.com/gain.html

    Gordon

  • mgraffeomgraffeo
    Steve, just need to make sure that the BB is the right size for your frame. There are two different sizes (Italian and English). One is more common than the other, I forget which is which.
  • Coach RichCoach Rich

    English threaded BB's are far, far more common.

  • Steven FordSteven Ford

    Thanks everyone, Gonna place order tomorrow, I was looking at Excel Sports in colorado but anyone have good suggestions on cheaper places?

     

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