Go Back  Bike Forums > Bike Forums > Framebuilders
Reload this Page >

Adding Disc Brake Tabs to Road Frame

Framebuilders Thinking about a custom frame? Lugged vs Fillet Brazed. Different Frame materials? Newvex or Pacenti Lugs? why get a custom Road, Mountain, or Track Frame? Got a question about framebuilding? Lets discuss framebuilding at it's finest.

Adding Disc Brake Tabs to Road Frame

Old 01-13-15, 12:04 PM
  #1  
Rocket-Sauce 
Port
Thread Starter
 
Rocket-Sauce's Avatar
 
Join Date: Jan 2008
Location: Boston
Posts: 7,326

Bikes: 2017 Soma Stanyan, 1990 Fuji Ace, 1990 Bridgestone RB-1, 1995 Independent Fabrications Track, 2003 Calfee Dragonfly Pro

Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 357 Post(s)
Liked 18 Times in 18 Posts
Adding Disc Brake Tabs to Road Frame

The best man from my wedding is looking for a lugged steel road frame with racy geometry that can have disc brakes. I'm looking for a fun winter project and would like to surprise him. I have two frames in mind, both similar quality: nice but not too nice. I have a 700c disc fork ready to go. I just need to get the disc brake tab, reinforcing strut and cable guide brazed on to the rear.

My question for you all is: Is this a tough job? I have heard from a few interested local frame builders and they either won't work on anything but their own frames or all quote ~$200+. That may be the going rate, but it puts the whole project over budget. Is that reasonable?

Are there any other options? Like going to a welding shop? I know this is a long shot, but felt I had to ask. I don't want to be cheap, just want to understand the cost. How labor intensive is this? I understand it requires more precision than adding, say, a cable guide, but the cost differential seems pretty high ($25 for the cable guide vs $175 for the brake tab).


THANKS
Rocket-Sauce is offline  
Old 01-13-15, 01:01 PM
  #2  
JohnJ80
Senior Member
 
Join Date: Feb 2011
Location: Minnesota
Posts: 4,003

Bikes: N+1=5

Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 532 Post(s)
Liked 5 Times in 5 Posts
Originally Posted by Rocket-Sauce View Post
The best man from my wedding is looking for a lugged steel road frame with racy geometry that can have disc brakes. I'm looking for a fun winter project and would like to surprise him. I have two frames in mind, both similar quality: nice but not too nice. I have a 700c disc fork ready to go. I just need to get the disc brake tab, reinforcing strut and cable guide brazed on to the rear.

My question for you all is: Is this a tough job? I have heard from a few interested local frame builders and they either won't work on anything but their own frames or all quote ~$200+. That may be the going rate, but it puts the whole project over budget. Is that reasonable?

Are there any other options? Like going to a welding shop? I know this is a long shot, but felt I had to ask. I don't want to be cheap, just want to understand the cost. How labor intensive is this? I understand it requires more precision than adding, say, a cable guide, but the cost differential seems pretty high ($25 for the cable guide vs $175 for the brake tab).


THANKS
Disc brakes change the whole stress profile on the frame. It's not as simple as just welding on the brake mounts. I think the $200 is more than reasonable (bargain) but I'd be cautious (as in run the other way) about anyone that is just going to attach the brake mounts and be done. Anyone who would do this properly would need to evaluate what the frame is built to do now and what other changes it would need. So it's not about just knowing how to attach the mounts, it's about knowing where, how and if the frame can handle it that matters.


J.
JohnJ80 is offline  
Old 01-13-15, 04:48 PM
  #3  
unterhausen
Randomhead
 
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 18,236
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 31 Times in 29 Posts
$200 is reasonable. Although I'm wondering if it can be done at all
unterhausen is offline  
Old 01-15-15, 10:27 AM
  #4  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,928

Bikes: 8

Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 6832 Post(s)
Likes: 0
Liked 211 Times in 176 Posts
Wheels Built Up With Drum Brake Hubs Retrofit Nicely without Frame Modifications , and have a Much Longer Service Free Life than Disc Brakes Too.

Last edited by fietsbob; 01-15-15 at 06:45 PM.
fietsbob is offline  
Old 01-15-15, 10:46 AM
  #5  
hueyhoolihan
Senior Member
 
Join Date: Dec 2010
Location: Above ground, Walnut Creek, Ca
Posts: 6,689

Bikes: 8 ss bikes, 1 5-speed touring bike

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 86 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
is it demonstrably different, as regards stresses, than running a coaster brake with an arm attached to only one chainstay?

BTW, 200 doesn't seem out of line, although it may well be out of one's budget. could just run a caliper in back and convince the best man that he's not that good.
hueyhoolihan is offline  
Old 01-15-15, 10:58 AM
  #6  
jimc101
Senior Member
 
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Posts: 5,447
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 289 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
From a non-frame builder, but technical perspective, what are you going to do about the spacing? Most all disc hubs are currently 135mm rear (many are wide, very few are 130mm) and road bikes are most commonly seen with 130mm rear OLD. Will the frame take this spreading?
jimc101 is offline  
Old 01-15-15, 10:58 AM
  #7  
unterhausen
Randomhead
 
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 18,236
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 31 Times in 29 Posts
when I said it might not be able to be done, I meant it might not fit. I am almost positive it isn't going to fit on the chainstay.
unterhausen is offline  
Old 01-16-15, 07:13 AM
  #8  
dsaul
Senior Member
 
Join Date: Jan 2013
Posts: 1,039
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked 28 Times in 22 Posts
This ^. Stick a disc wheel in the frame and make sure the disc clears the stay before doing anything else.
dsaul is offline  
Old 01-19-15, 04:18 PM
  #9  
squirtdad
Senior Member
 
squirtdad's Avatar
 
Join Date: Jul 2006
Location: San Jose (Willow Glen) Ca
Posts: 6,123

Bikes: 90/91 De Rosa, '84 Team Miyata, '82 nishiski,

Mentioned: 55 Post(s)
Tagged: 0 Thread(s)
Quoted: 806 Post(s)
Liked 36 Times in 28 Posts
check out this thread http://www.bikeforums.net/framebuild...ons-traps.html lot's of info...
__________________
Looking for Team Miyata F&F 58cm
squirtdad is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bruce19
Road Cycling
2
09-04-18 05:30 AM
LateStart
Classic and Vintage Bicycles: Whats it Worth? Appraisals.
6
11-20-13 02:44 PM
Sfuse
BMX
2
10-23-07 07:54 PM
socalrider
Road Cycling
25
07-01-05 09:35 AM
rykoala
Commuting
2
10-08-04 07:03 PM

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

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