Results 1 to 10 of 10
  1. #1
    a real member's member
    Reputation: blackfrancois's Avatar
    Join Date
    Jul 2016
    Posts
    3,486

    how do you true chainrings?

    for slightly bent chainrings, what do you do? take it off the arm first? leave it on? use vise-grips (and maybe a rag on the ring to protect damage)? use a special tool? live with it? ever made the slight problem worse?
    Yossarian: don't worry. nothing's going to happen to you that won't happen to the rest of us.

  2. #2
    RoadBikeReview Member
    Reputation:
    Join Date
    Dec 2006
    Posts
    3,850
    I have a special tool-can't remember what brand it is or where I got it.

    It's rectangular steel stock about 9" long and 1"+tall. A slot is cut into the 1" tall section near each end; they vary in width to accommodate different chainring widths (think of a thick ruler). Usually you slip it onto the chainring spider arms while the ring is mounted to the crank, to bend the chainring into plane.

    I've never made the problem worse; just kept tweaking until it was straight enough.

  3. #3
    Cleavage Of The Tetons
    Reputation:
    Join Date
    Feb 2005
    Posts
    293

  4. #4
    'brifter' is a lame word.
    Reputation: cxwrench's Avatar
    Join Date
    Nov 2004
    Posts
    13,026
    If it's a flat aluminum ring then do what rideit says above. If it's a Shimano hollow ring buy a new one.
    I work for some bike racers
    I've got some bikes, some guns,
    and a bunch of skateboards

  5. #5
    Russian Troll Farmer
    Reputation: No Time Toulouse's Avatar
    Join Date
    Sep 2016
    Posts
    1,610
    I generally take it off the bike, put it in the vise at work (protected by a rag), and start tweaking it with a bar (I have a super-heavy-duty screwdriver that works well), then I take it over to the plate, and measure runout with an indicator. I can get them to within .001" if I have the time. Having a full machine shop at my disposal is a help, though..
    "L'enfer, c'est les autres"

  6. #6
    Cleavage Of The Tetons
    Reputation:
    Join Date
    Feb 2005
    Posts
    293
    Quote Originally Posted by cxwrench View Post
    If it's a flat aluminum ring then do what rideit says above. If it's a Shimano hollow ring buy a new one.
    Good point!

  7. #7
    RoadBikeReview Member
    Reputation: velodog's Avatar
    Join Date
    Sep 2007
    Posts
    6,927
    Quote Originally Posted by rideit View Post
    This.
    Too old to ride plastic

  8. #8
    RoadBikeReview Member
    Reputation:
    Join Date
    Feb 2002
    Posts
    20,786
    Quote Originally Posted by rideit View Post
    Use a bigger wrench to get more of the ring between the jaws. The picture is of an 8" - I prefer 12". And note that with aluminum cranks, it is often one of the spider arms that is tweaked rather than the ring.

  9. #9
    a real member's member
    Reputation: blackfrancois's Avatar
    Join Date
    Jul 2016
    Posts
    3,486
    thanks, all.
    Yossarian: don't worry. nothing's going to happen to you that won't happen to the rest of us.

  10. #10
    Cleavage Of The Tetons
    Reputation:
    Join Date
    Feb 2005
    Posts
    293
    Quote Originally Posted by Kerry Irons View Post
    Use a bigger wrench to get more of the ring between the jaws. The picture is of an 8" - I prefer 12". And note that with aluminum cranks, it is often one of the spider arms that is tweaked rather than the ring.
    Yeah, I just used the first image that popped up. 12" is better (heheh...that's what she said)

Similar Threads

  1. Wheels: How true is true enough?
    By dinga in forum Wheels and Tires
    Replies: 23
    Last Post: 05-13-2016, 11:02 AM
  2. How to true chainrings ?
    By Ab24029 in forum Components, Wrenching
    Replies: 10
    Last Post: 03-11-2006, 05:27 PM
  3. Calling all deep carbon rim owners: How true is true?
    By BikinBrian in forum Components, Wrenching
    Replies: 8
    Last Post: 11-01-2004, 11:41 AM
  4. Calling all deep carbon rim owners: How true is true?
    By BikinBrian in forum General Cycling Discussion
    Replies: 7
    Last Post: 11-01-2004, 06:08 AM
  5. Calling all deep carbon rim owners: How true is true?
    By BikinBrian in forum Components, Wrenching
    Replies: 1
    Last Post: 10-30-2004, 08:38 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
  •  

THE SITE

ABOUT ROADBIKEREVIEW

VISIT US AT

roadbikereview.com and the ConsumerReview Network are business units of Invenda Corporation

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