Results 1 to 7 of 7
  1. #1
    mtbr member
    Join Date
    Jun 2016

    New to MTB fit. What length stem to start with?

    Expecting my hardtail frame next week and the last pieces of the build are the cockpit components. I feel I have my road fit pretty well down.

    I'm going to be using the Thomson Trail bar. 750mm wide, 12mm rise, 6d backsweep.

    Current road bike
    Stack: 603mm
    Reach: 378mm (57cm TT)
    Stem: 0d 100mm
    Bar: 120mm reach/130mm drop (randonneur bend)

    MTB frame (Lynskey Ridgeline 29SL size L)
    Stack: 651mm
    Reach: 423mm

    If I add some figures to get a general effective "reach" of where I put my hands (assuming same saddle setback for both frames) then I get something like 598mm (378+100+120) for the road bike.

    Doesn't seem that's very useful for choosing a MTB stem as I don't know how to account for the large disparity in handlebar width and the fact that MTB position is generally more upright.

    I realize this is something that you can't just do on paper and it's a trial and error kinda thing, the human body is adaptable, and on and on. But where should I (where would you) start? 70mm 0d stem? Longer? Shorter?


  2. #2
    I Tried Them ALL... SuperModerator
    Reputation: Cayenne_Pepa's Avatar
    Join Date
    Dec 2007
    I'd start with 70mm.
    "This is a male-dominated forum... there will be lots of Testosterone sword-shaming here" ~ Kenfucius

  3. #3
    mtbr member
    Reputation: ser jameson's Avatar
    Join Date
    Jun 2012
    A complete bike would have been a better choice for a first mtb.
    Just go with the 70, and adjust it if you feel it should be longer or shorter. Though, I'm not sure how you'll know if your stem is the wrong length, because of your limited experience.
    Always get a complete bike for your first one.

    Sent from my iPhone using Tapatalk

  4. #4
    mtbr member
    Join Date
    Jun 2016
    Quote Originally Posted by Cayenne_Pepa View Post
    I'd start with 70mm.
    Thank you.

    Quote Originally Posted by ser jameson View Post
    Always get a complete bike for your first one.
    Oh, man. I really messed up.

  5. #5
    mtbr member
    Reputation: d365's Avatar
    Join Date
    Jun 2006
    A lot of shops have multiple stems used for testing fit.... that would be where I'd start, in your case.

  6. #6
    Fat-tired Roadie
    Reputation: AndrwSwitch's Avatar
    Join Date
    Nov 2007
    For that bike, I'd probably start with 80. Maybe even 90 since it sounds like your frames have a smaller reach difference than my road and XC frames.

    I probably use about 10 mm less drop on my XC bikes and land the reach to my grips somewhere between the reach to my flats and to my brake hoods.

    As others have said, start with cheap or, better yet, loaner stems.

    I bumped into a nice comparison of road vs. XC fit over on XC Racing and Training the other day. The poster said that road fit was about power, comfort and aero. MTB fit is about power, comfort and weight distribution. In other words, look for the right fit to let you kick out a lot of Watts, not hurt you, and have neutral handling on climbs and descents. Different MTB disciplines will have different attitudes.

    Pretty bike. Post pics when you get it to the top of something.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  7. #7
    mtbr member
    Join Date
    Jun 2016
    Many thanks for the guidance, all.

Similar Threads

  1. Stem Length vs Top Tube Length?
    By biggrumble in forum All Mountain
    Replies: 30
    Last Post: 05-21-2016, 08:17 PM
  2. Stem Length
    By fatboy43 in forum Fat bikes
    Replies: 12
    Last Post: 04-21-2015, 05:42 AM
  3. Replies: 1
    Last Post: 09-19-2014, 06:51 PM
  4. Sizing - Top Tube Effective Length and Stem Length
    By noonievut in forum Beginner's Corner
    Replies: 11
    Last Post: 02-13-2014, 03:26 AM
  5. How does stem length and frame length affect handling
    By Fargo1 in forum Beginner's Corner
    Replies: 12
    Last Post: 10-31-2012, 07:23 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



VISIT US AT and the ConsumerReview Network are business units of Invenda Corporation

(C) Copyright 1996-2018. All Rights Reserved.