Quantcast
MTB: 170 vs 175 cranks - Beyond.ca - Car Forums

View Poll Results: Crank length

Voters
3. You may not vote on this poll
  • 170mm

    1 33.33%
  • 175mm

    1 33.33%
  • Doesn't matter, just fucking ride.

    1 33.33%
Multiple Choice Poll.
Results 1 to 6 of 6

Thread: MTB: 170 vs 175 cranks

  1. #1
    Join Date
    Nov 2002
    Location
    Not Aspen
    My Ride
    Two from Freemont
    Posts
    9,807
    Rep Power
    45

    Default MTB: 170 vs 175 cranks

    I'm building up a Tallboy and am wondering if you guys think there is a difference. Internet is mixed.

    I've ordered 170mm, but I might bump up to 175mm.

    Current Nomad has 27.5" wheels, Eagle drivetrain (10-50) and 170mm cranks and 30T chainring. No issues with knee pain or anything. Going up steep stuff is a geometry limitation rather than a "power" limitation.

    Going XT on the Tallboy (10-51) with a 30T chainring. With 29" wheels and the 51 in the rear, the gearing is the same with 175mm cranks.

    170mm cranks should make pedaling 6% harder than what I am used to now. Is that even perceptable?

    170 or 175 or it doesn't fucking matter, just ride.

  2. #2
    Join Date
    May 2005
    Location
    calgary
    My Ride
    Wankels!
    Posts
    290
    Rep Power
    19

    Default

    Personally I'd go with 170mm because you know it works for your knees. You can set your saddle height to the exact same as the Nomad and be on your way. No cleat adjustment needed either if you're on clipless. Like you said, it's not a power limitation so going up to 29er wheel probably won't be an issue for you.

  3. #3
    Join Date
    May 2005
    Location
    Calgary
    Posts
    819
    Rep Power
    19

    Default

    Moreso dependent on your inseam than anything, and a 5mm change will be barely noticeable. I would suggest a 32 or 34 chainring. 30x51 is way too low of a ratio, especially for a xc duty bike.

  4. #4
    Join Date
    Apr 2008
    Location
    calgary
    My Ride
    CLK 55 / 2g Eclipse / EP3
    Posts
    4,422
    Rep Power
    22

    Default

    haha, I had a 170 and 175mm cranks for a while and never noticed it - now with my 29" bike I have 180s.

  5. #5
    Join Date
    Nov 2002
    Location
    calgary
    Posts
    1,238
    Rep Power
    23

    Default

    The other consider here is clearance. Are you hitting your cranks on the ground right now with your Nomad? The TB sits another 10mm lower in bb height compared to the nomad so if you went to 175 you might have issues as you would losing 1.5cm in clearance, id stick with 170mm.

  6. #6
    Join Date
    Nov 2002
    Location
    Not Aspen
    My Ride
    Two from Freemont
    Posts
    9,807
    Rep Power
    45

    Default

    Update: Went with 175mm

    Don’t notice a difference pedalling at all.
    Descending, though, I can definitely tell that my feet are further apart.

Similar Threads

  1. Pontiac Vibe cranks but won't start

    By ZZT23 in forum Mechanical
    Replies: 19
    Latest Threads: 11-28-2015, 11:06 AM
  2. FS: XTR wheelset/MTB SPD Pedals/LG-MTB shoes/Suunto GPS HR watch

    By RickDaTuner in forum Fitness & Sports Equipment
    Replies: 1
    Latest Threads: 08-22-2013, 07:29 PM
  3. Replies: 3
    Latest Threads: 09-07-2010, 05:23 PM
  4. $170 of Underground Clothing for $130

    By mwmhong in forum Miscellaneous Buy/Sell/Trade
    Replies: 8
    Latest Threads: 07-17-2003, 03:42 PM
  5. WTB: BMX parts 3-Piece Cranks, bars, stem, sprocket.

    By skyway in forum Miscellaneous Buy/Sell/Trade
    Replies: 0
    Latest Threads: 07-15-2003, 02:14 PM

Posting Permissions

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