Is there any benifits going to 170mm cranks from 175mm cranks?- Mtbr.com
Results 1 to 7 of 7
  1. #1
    mtbr member
    Reputation: drumstix's Avatar
    Join Date
    Dec 2003
    Posts
    2,284

    Is there any benifits going to 170mm cranks from 175mm cranks?

    Hola, I have been using 175mm cranks for ever, I know that in DH smaller cranks are used alot, and I have been seeing alot of FR bikes with the shorter cranks, how about trailriding?
    I guess its 5mm shorter so you might miss a rock here or there, what about power or torque for climbing? Or a quick power stroke of the pedals to lift the front end over something, any difference, good or bad?

    BTW, Im on the shorter spectrum, a few clicks under 5'7", and Im building up a Bullit with a 05 Z1 and mostly trailbike parts that will take a big hit because I didnt see it coming!

  2. #2

    Reputation:
    Join Date
    Jan 2004
    Posts
    5,261
    generally people are running 170 or 165s to gain clearance; you'd be surprised at how much 5-10mm will make a difference in missing rocks under power.

    It will change your gearing, but this can compensated by changing your chainring size. More picky types (like roadies) select it by the feel of the stroke.

  3. #3
    mtbr member
    Reputation: Go Kart Motzart's Avatar
    Join Date
    Jan 2004
    Posts
    1,238
    Quote Originally Posted by zedro
    It will change your gearing, but this can compensated by changing your chainring size.
    Huh?

    The only upside is 5mm more ground clearance, which on a trail bike may not matter. The downside is you lose a little leverage (2.8%) and your seat will have to come up 5mm to keep the same leg extension therefore raising your center of gravity. If you've been riding 175's and don't have any complaints I would probably stick with em'.
    Last edited by Go Kart Motzart; 12-07-2004 at 04:38 AM.

  4. #4

    Reputation:
    Join Date
    Jan 2004
    Posts
    117
    I run them on my fr/dh bike and I can't tell they are shorter as far as pedaling goes. I do notice that I am not clipping as many rock during my rides. I do a fair amount of trailriding on this bike and I don't feel that I am at any disadvantage by using 170mm cranks.

  5. #5

    Reputation:
    Join Date
    Jan 2004
    Posts
    5,261
    Quote Originally Posted by Go Kart Motzart
    Huh?

    The downside is you lose a little leverage (2.8%) ....
    thats what i said, and you can compensate by changing your front chainring size...i'm not crazy....

  6. #6
    mtbr member
    Reputation: drumstix's Avatar
    Join Date
    Dec 2003
    Posts
    2,284
    Quote Originally Posted by zedro
    thats what i said, and you can compensate by changing your front chainring size...i'm not crazy....

    Would that be adding or subtracting teeth to compensate?

  7. #7

    Reputation:
    Join Date
    Sep 2004
    Posts
    97
    subtracting, go down about 2 teeth for the same leverage with a decrease from 175 to 170

Similar Threads

  1. 175mm vs 170mm cranks
    By r1Gel in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 1
    Last Post: 12-06-2004, 01:39 PM
  2. pls help need 170mm square taper compact cranks
    By ashwinearl in forum Weight Weenies
    Replies: 7
    Last Post: 05-28-2004, 11:36 AM
  3. Same or longer crank length on MTB vs Road bike
    By ashwinearl in forum XC Racing and Training
    Replies: 8
    Last Post: 05-20-2004, 01:56 PM
  4. 170mm cranks needed
    By mikesee in forum 29er Bikes
    Replies: 0
    Last Post: 04-28-2004, 10:23 PM
  5. 170mm vs. 175mm Crank Arms
    By CrashTheDOG in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 2
    Last Post: 04-03-2004, 09:46 AM

Members who have read this thread: 1

Posting Permissions

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

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2020 VerticalScope Inc. All rights reserved.