bottom bracket sizing and spindle length- Mtbr.com
Results 1 to 9 of 9
  1. #1
    mtbr member
    Reputation:
    Join Date
    Dec 2005
    Posts
    54

    bottom bracket sizing and spindle length

    hi, i am converting an old ritchey P22 into a single speed and was wondering how to measure the bottom bracket and determine spindle length. thanks for any help.

  2. #2
    mtbr member
    Reputation: Mudflaps's Avatar
    Join Date
    Sep 2005
    Posts
    1,155

    More info needed

    To get a start to make a decent recommendation, what crank are you planning to use and which rear wheel?
    For instance, if you're going to use a multi-gear wheel (as I did) you have lots of flexibility in BB spindle length since you're free to place your rear cog in any of several locations laterally by use of spacers. I used the between-cog spacers from a couple of cassettes and found a good chainline to match my crank placement.

    If you're going to use a SS specific wheel, suggest checking the use of the info on White Industries site regarding their Eno cranks. http://www.whiteind.com/ENO_Products...rank_info.html
    This can give you the idea as to what all needs to be considered/measured in the choices you are about to make.




    Quote Originally Posted by dirty_garage
    hi, i am converting an old ritchey P22 into a single speed and was wondering how to measure the bottom bracket and determine spindle length. thanks for any help.

  3. #3
    poser Administrator
    Reputation: rockcrusher's Avatar
    Join Date
    Aug 2003
    Posts
    9,458
    The other measurements that you will need is the size of the bottom bracket shell which will either be 68mm or 73mm. This will determine the length of BB housing that you need. BB's are sold as a double size measure usually something like 112x68mm

    the 112 is the length of the spindle. New spindles for new cranks, such as isis or octalink compatible will use a length of between 107 and 112mm.

    If you are going old school and are using a square taper BB and some old crank arms then it will tend toward 112 to 120mm or even larger again depending on your choice in rear wheel.

    If you are going square taper I would buy the shortest length (~112mm) that you can since with a 32-36 up front you will not likely have clearance problems with the chainstays.

    The others you will have to test fit.

    Some manufacturers make an isis bb that has no fixed cup and allows chainline adjustment through screwing/unscrewing the cups in the BB. This is a good option if you cannot get better information.

    2 piece cranks, you got me.
    MTBR Posting Guidelines
    calories>electrons

  4. #4
    Occasionally engagedů
    Reputation: Ptor's Avatar
    Join Date
    Jan 2004
    Posts
    1,640
    I have an old Bridgestone MB1 built as a SS. It has a Ritchey Logic Crank (not compact) that is mated to a 119 mm Phil Wood BB. It has an insanely small Q-factor, about 145 mm and barely clears the chainstays. I have another SS built with Ritchey Logic Cranks, the compact version. It uses a Phil Wood BB that is 108 mm and the Q-factor is 154 mm. These two cranks look very similar, give identical chainlines, but have different Q-factors and different length BB (with the smaller Q-factor having the longer BB spindle). Most cranks are designed to give the standard chainline with a very specific spindle length -- it's complicated. Go visit Sheldon Brown's site to figure it out!

    http://sheldonbrown.com/harris/cranks.html
    "The plural of anecdote is not data." -- Attributed to various people in a variety of forms, but always worth remembering...

  5. #5
    mtbr member
    Reputation:
    Join Date
    Dec 2005
    Posts
    54

    thanks

    very helpful responses...mucho appreciated. i am going to put on white industries eno cranks with a phil wood spindle (hopefully this will work) and am thinking of a 34t with a 17t WI eno rear. the hub is a phil wood ss.
    pet that is a very helpful website...thanks
    i am also hoping this set-up will work when i upgrade frames but for now i want to abuse my ritchey as it has limited miles on but just older.
    tensioner recommendations would be appreciated if you all have one.
    thanks again

  6. #6
    Occasionally engagedů
    Reputation: Ptor's Avatar
    Join Date
    Jan 2004
    Posts
    1,640
    Quote Originally Posted by dirty_garage
    thinking of a 34t with a 17t WI eno rear. the hub is a phil wood ss.
    ...tensioner recommendations would be appreciated if you all have one.
    Here's one more site that might be useful:

    http://eehouse.org/fixin/index.php

    It has a calculator that determines what gearing would work for a "magic gear" on your frame (no tensioner). I can run a 36x18 on my MB-1 pretty easily, but I did end up mounting an old front derraileur at the crank to prevent the chain from being thrown -- very unobtrusive and doesn't detract from the clean lines and simplicity of the SS experience.

    Finally, does the P22 have 135 or 130 rear spacing? My old MB-1 is 130 and it was Ritchey inspired...
    "The plural of anecdote is not data." -- Attributed to various people in a variety of forms, but always worth remembering...

  7. #7
    mtbr member
    Reputation:
    Join Date
    Dec 2005
    Posts
    54
    "Finally, does the P22 have 135 or 130 rear spacing? My old MB-1 is 130 and it was Ritchey inspired..."
    i dunno off hand but will check it in the am. thanks again

  8. #8
    No Justice = No Peace
    Reputation: Lutarious's Avatar
    Join Date
    Feb 2005
    Posts
    1,512

    rear wheel choices

    You can use an ENO hub and forget the tensioner..... But you knew that.

    as for spacing, it's easy to get a good shop or frame builder to set your stays in or out to match a wheel. 130 to 135 is no big deal...
    "Welcome to my underground lair...."

  9. #9
    mtbr member
    Reputation: minor swing's Avatar
    Join Date
    Nov 2005
    Posts
    233

    frame setting pretty cheap

    Quote Originally Posted by Lutarious
    You can use an ENO hub and forget the tensioner..... But you knew that.

    as for spacing, it's easy to get a good shop or frame builder to set your stays in or out to match a wheel. 130 to 135 is no big deal...
    I have an old KHS Crest frame that I ss'd out. Someone prior to me has reset the rear spacing down to about 110. I had an LBS reset to 135 for $15. It is straight as can be and rides great.

Members who have read this thread: 2

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 2019 VerticalScope Inc. All rights reserved.