Go Back  Bike Forums > Bike Forums > Classic & Vintage > Classic and Vintage Sales
Reload this Page >

I need a chainring straightener

Notices
Classic and Vintage Sales Private Sales Only, no online storefronts. All prices must be quoted, we are not an auction site.

I need a chainring straightener

Old 11-28-20, 01:13 AM
  #1  
Road Fan
Senior Member
Thread Starter
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 15,160

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 1167 Post(s)
Liked 171 Times in 149 Posts
I need a chainring straightener

I have a few bikes to refurbish for a friend and his wife (matching his/hers wedding gifts), and the 45+ year old steel chainrings are warped. New chainsets are not an option.

I need a Bicycle Research Chainring Straightener. Anybody have one or similar to sell? There was one on Ebay recently but I missed it.

EDIT: I've bought something that I think will do the trick - see below for the story.

Last edited by Road Fan; 12-12-20 at 10:06 PM.
Road Fan is offline  
Old 11-28-20, 02:10 AM
  #2  
reconnaissance
Senior Member
 
Join Date: Sep 2016
Location: Texas Hill Country
Posts: 112

Bikes: Trek 850, Trek 510, Cannondale 300m, Specialized Rockhopper, Stumpjumper, Bianchi Virata

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 37 Post(s)
Liked 80 Times in 28 Posts
I use an adjustable wrench. Crescent wrench.
https://en.wikipedia.org/wiki/Adjustable_spanner
reconnaissance is offline  
Likes For reconnaissance:
Old 11-28-20, 06:02 AM
  #3  
oneclick 
Senior Member
 
Join Date: Feb 2020
Posts: 643
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 219 Post(s)
Likes: 0
Liked 212 Times in 137 Posts
Originally Posted by reconnaissance View Post
I use an adjustable wrench. Crescent wrench.
https://en.wikipedia.org/wiki/Adjustable_spanner
Yes.

Old big ones are the best, they've got lots of surface area, they usually have tighter jaws, and the larger thumbscrew lets you get a good firm grip.

And steel ones are usually easy - most of the ones I've dealt with bent at mounting holes where the metal is smallest in cross-section; what you do is watch the chrome surface reflection in a good light and you can see when each arm is flat. If it's a separable ring you can also grip it from inside, and tweak each branch of the arm-at-the-hole.
oneclick is offline  
Old 11-28-20, 07:01 AM
  #4  
ARider2
Senior Member
 
Join Date: Dec 2009
Posts: 367
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 25 Post(s)
Liked 32 Times in 24 Posts
I have used the Park Tool rotor truing fork for straightening chainrings. It has a long slot that works well for most cases...


ARider2 is offline  
Old 11-28-20, 07:55 AM
  #5  
mountaindave 
tantum vehi
 
mountaindave's Avatar
 
Join Date: Jul 2008
Location: Flathead Valley, MT
Posts: 3,675

Bikes: More than I care to admit

Mentioned: 111 Post(s)
Tagged: 0 Thread(s)
Quoted: 817 Post(s)
Liked 168 Times in 118 Posts
+1 on both of the above ideas
mountaindave is offline  
Old 11-30-20, 12:05 PM
  #6  
rhm
multimodal commuter
 
rhm's Avatar
 
Join Date: Nov 2006
Location: NJ, NYC, LI
Posts: 19,562

Bikes: 1940s Fothergill, 1959 Allegro Special, 1963? Claud Butler Olympic Sprint, Lambert 'Clubman', 1974 Fuji "the Ace", 1976 Holdsworth 650b conversion rando bike, 1983 Trek 720 tourer, 1984 Counterpoint Opus II, 1993 Basso Gap, 2010 Downtube 8h, and...

Mentioned: 511 Post(s)
Tagged: 0 Thread(s)
Quoted: 1761 Post(s)
Liked 250 Times in 170 Posts
Originally Posted by Road Fan View Post
I have a few bikes to refurbish for a friend and his wife (matching his/hers wedding gifts), and the 45+ year old steel chainrings are warped. New chainsets are not an option.

I need a Bicycle Research Chainring Straightener. Anybody have one or similar to sell? There was one on Ebay recently but I missed it.
I have that tool and am willing to lend it; send me a private message and we can work out the details.
__________________
www.rhmsaddles.com.
rhm is offline  
Likes For rhm:
Old 11-30-20, 01:46 PM
  #7  
juvela
Senior Member
 
juvela's Avatar
 
Join Date: Feb 2013
Location: Alta California
Posts: 10,113
Mentioned: 289 Post(s)
Tagged: 1 Thread(s)
Quoted: 2308 Post(s)
Liked 536 Times in 444 Posts
-----

tip -

unless you can see visible runout right at the teeth it is best to make your adjustments down as low (close to the centre) as possible

some deformations are best resolved by cold setting the spider itself

the Bicycle Research tool is called the Lajeunesse for a mechanic at the shop whose name is Dan Lajeunesse and who created it

used to visit with him at the shop in Concord Califiornia back in the 1970's as we had purchased the same model of pickup truck and would exchange information on that

Dan is also a guitarist/guitar maker

Bicycle Research Products is a creation of Don Millberger, formerly an employee at Lawrence Livermore Laboratory

-----

Last edited by juvela; 11-30-20 at 01:49 PM. Reason: spellin'
juvela is offline  
Likes For juvela:
Old 12-12-20, 10:03 PM
  #8  
Road Fan
Senior Member
Thread Starter
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 15,160

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 1167 Post(s)
Liked 171 Times in 149 Posts
Originally Posted by juvela View Post
-----

tip -

unless you can see visible runout right at the teeth it is best to make your adjustments down as low (close to the centre) as possible

some deformations are best resolved by cold setting the spider itself

the Bicycle Research tool is called the Lajeunesse for a mechanic at the shop whose name is Dan Lajeunesse and who created it

used to visit with him at the shop in Concord Califiornia back in the 1970's as we had purchased the same model of pickup truck and would exchange information on that

Dan is also a guitarist/guitar maker

Bicycle Research Products is a creation of Don Millberger, formerly an employee at Lawrence Livermore Laboratory

-----
@rhm, Always generous, thank you so much!

@juvela, your advice matches my intuition, to make the adjustments down low. I already took a shot at that with my 14" adjustable and it's really too big to get in and bend things under good control.

Bottom line to all, I found a few of the Park tool on 'Bay, so I bought one.

As well, Juvela the tale of the history of Bicycle Research is interesting. I worked with some Livermore folks for a few years. I also had a colleague at Ford who was a physicist working as a mechanical engineer, and for the price of a few Mexican lunches, he made me a headset cup press. I made up a set of dimensions for a Campy Strada headset and the head tube on my Masi, and he designed cups and turned them on his lathe. I've never had problems with headsets on steel frames since. He also made me a ram for cup extraction, but its pretty hard to get it in place, so I'm still down to a big punch and a 1 lb hammer. It works quite well!

Any case I'd say my chainring need is settled.
Road Fan is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.