Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Classic & Vintage This forum is to discuss the many aspects of classic and vintage bicycles, including musclebikes, lightweights, middleweights, hi-wheelers, bone-shakers, safety bikes and much more.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 08-13-12, 05:19 PM   #1
ParaWK4
Senior Member
Thread Starter
 
ParaWK4's Avatar
 
Join Date: Jul 2008
Location: Indiana
Bikes: 85 Fuso, 86 Peloton, 84,88 Paramount
Posts: 156
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Dura Ace Brake Barrel O-Rings

One of the o-rings on an adjusting barrel of my Dura Ace 7402 brakes cracked in two. I did some measuring and looking around for a replacement. I got a few replacement o-rings 11 mm inside diameter and 3 mm thickness. The attached pictures show the cracked and new rings. The 3mm thickness looks a little thin compared to the original and I should have gotten 3.5 mm or so. Anyone else have a cracked o-ring like this ?? At 20 cents each I bought a lifetime supply and if anybody needs one, drop me a note.
Attached Images
File Type: jpg IMG_0929.jpg (91.8 KB, 3 views)
File Type: jpg IMG_0930.jpg (97.1 KB, 6 views)
File Type: jpg IMG_0931.jpg (89.9 KB, 7 views)
ParaWK4 is offline   Reply With Quote
Old 08-13-12, 05:33 PM   #2
Chombi 
Senior Member
 
Chombi's Avatar
 
Join Date: Jul 2009
Bikes: 1986 Alan Record Carbonio, 1985 Vitus Plus Carbone 7, 1984 Peugeot PSV, 1972 Line Seeker, 1986(est.) Medici Aerodynamic (Project), 1985(est.) Peugeot PY10FC
Posts: 10,809
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
My experience with most automotive type o-rings that I had re-purposed for my bike componentd is that they tend to dry out and crack after just a short time as I think they might be more sensitive to gasses commonly encountered in the environment like Ozone. They last longer in machinery as they are mostly sealed away from these gasses and UV light. I dunno, but has anyone here experienced similar??

Chombi
Chombi is offline   Reply With Quote
Old 08-13-12, 05:57 PM   #3
repechage
Senior Member
 
Join Date: Jun 2006
Bikes:
Posts: 10,780
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 35 Post(s)
Quote:
Originally Posted by Chombi View Post
My experience with most automotive type o-rings that I had re-purposed for my bike componentd is that they tend to dry out and crack after just a short time as I think they might be more sensitive to gasses commonly encountered in the environment like Ozone. They last longer in machinery as they are mostly sealed away from these gasses and UV light. I dunno, but has anyone here experienced similar??

Chombi
Most "O" rings are a form of nitrile. Not all nitrile is the same. There are other compositions, look up O rings in Mc Master-Carr or Grainger for the size you need. Note there are also metric "O" rings, I bought some of those for my Campagnolo adjusters. Silicone ones are often found in Blue...or Red.

The images finally loaded, Look for Silicone.
repechage is offline   Reply With Quote
Old 08-14-12, 10:34 AM   #4
zebede
Hello
 
zebede's Avatar
 
Join Date: Aug 2007
Location: Suncoast, Florida
Bikes: BF Tikit, Dahon Speed TR, Mezzo I4, Miyata 610, Gitane Criterium, Dahon Helios XL
Posts: 593
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Green for A/C refrigerant work can be found at well stocked AutoParts Stores. A little more expensive but are high quality.
zebede is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 12:27 PM.