Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Stripped Disc Brake mounting threads in fork

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Stripped Disc Brake mounting threads in fork

Old 01-25-23, 09:15 AM
  #1  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
Stripped Disc Brake mounting threads in fork

Any way to fix stripped threads in a fork? I don't want to replace the entire fork... I don't think there is enough material for a tap/helicoil type fix.

2019 Giant TXC, carbon fiber, for reference.

PS - I plan to have a pro do this work, just didn't even know if its possible.

Thanks!!

Last edited by Jughed; 01-25-23 at 09:22 AM.
Jughed is offline  
Old 01-25-23, 11:06 AM
  #2  
GamblerGORD53
Senior Member
 
Join Date: Apr 2010
Location: Elevation 666m Edmonton Canada
Posts: 2,169

Bikes: 2013 Custom SA5w / Rohloff Tourster

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 1058 Post(s)
Liked 226 Times in 177 Posts
Can't see without pics.
GamblerGORD53 is offline  
Old 01-25-23, 01:21 PM
  #3  
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 36,931

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 132 Post(s)
Tagged: 1 Thread(s)
Quoted: 4884 Post(s)
Liked 925 Times in 555 Posts
In most cases it should be possible to drill out the thread and mount the brake with a bolt and nut.

It's not a difficult job, and done right, as good as new for practical purposes.

BTW don't let assumptions prevent consideration of a coil insert. These don't involve removing much and in soft materials produce a stronger thread than original.

Last edited by FBinNY; 01-25-23 at 01:29 PM.
FBinNY is offline  
Likes For FBinNY:
Old 01-25-23, 01:28 PM
  #4  
alcjphil
Senior Member
 
alcjphil's Avatar
 
Join Date: Jun 2002
Location: Montreal, Quebec
Posts: 5,434
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 1589 Post(s)
Liked 1,316 Times in 773 Posts
What type of mount for the calliper? If it is a flat mount a helical might be the only solution. Either that or tapping the mount out to a larger size and using a larger mounting bolt
alcjphil is offline  
Old 01-25-23, 01:49 PM
  #5  
jimc101
Senior Member
 
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Posts: 5,754
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 441 Post(s)
Liked 93 Times in 79 Posts
How did you do this? was it user error, or a defect that would/maybe be covered under warranty (you get lifetime as the original owner if a defect)

Would look at the cost of a replacement fork vs Helicoil, there isn't much material on a tab to fit one (the 2019 Giant TXC has flat mount), and unless doing it yourself, a LBS may refuse as there is the liability issue for a safety critical part
jimc101 is offline  
Likes For jimc101:
Old 01-25-23, 02:33 PM
  #6  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
Originally Posted by GamblerGORD53 View Post
Can't see without pics.
will try to get a pic...
Jughed is offline  
Old 01-25-23, 02:41 PM
  #7  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
To answer some of the above questions:

Flat mount
There is very little material.

I am the second owner. See my post on the Chinese frame thread - when the aftermarket Chinese bars exploded and I crashed, that side of the bike.

I took everything apart to check inspect everything for cracks, went to put the nut back in and it just spun in there, probably got torn up in the crash. Took it to Giant for a frame inspection - it passed... asked them to fix that along with other issues and they made a mess of the bike. I had the new bars and hoods loosely put on - I asked them to level the bars, correctly mount the hoods, torque everything and put on bar tape, fix the fork... they only put on bar tape, everything else was loose and in the same position I left it in. So I wont go back to that shop...

I guess I need to find a better LBS that can actually do real work. I asked here first to see if its even possible to fix.

Thanks
Jughed is offline  
Old 01-25-23, 07:10 PM
  #8  
Shadco 
Resident PIA
 
Shadco's Avatar
 
Join Date: Jul 2004
Location: City of Oaks, NC
Posts: 647

Bikes: Gunnar Roadie, Look 765 Optimum

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 134 Post(s)
Liked 232 Times in 117 Posts
Originally Posted by Jughed View Post
To answer some of the above questions:

Flat mount
There is very little material.

I am the second owner. See my post on the Chinese frame thread - when the aftermarket Chinese bars exploded and I crashed, that side of the bike.

I took everything apart to check inspect everything for cracks, went to put the nut back in and it just spun in there, probably got torn up in the crash. Took it to Giant for a frame inspection - it passed... asked them to fix that along with other issues and they made a mess of the bike. I had the new bars and hoods loosely put on - I asked them to level the bars, correctly mount the hoods, torque everything and put on bar tape, fix the fork... they only put on bar tape, everything else was loose and in the same position I left it in. So I wont go back to that shop...

I guess I need to find a better LBS that can actually do real work. I asked here first to see if its even possible to fix.

Thanks
So Ö

They used to be a giant dealer but arenít any longer. Bike Doctor in Arnold MD talk to Steve if he is in. They are a great shop.

cheers
__________________
--
Shad
I knew where I was when I wrote this
I don't know where I am now...
05 Gunnar Roadie Chorus/Record
67'er
Shadco is offline  
Old 01-25-23, 09:07 PM
  #9  
GamblerGORD53
Senior Member
 
Join Date: Apr 2010
Location: Elevation 666m Edmonton Canada
Posts: 2,169

Bikes: 2013 Custom SA5w / Rohloff Tourster

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 1058 Post(s)
Liked 226 Times in 177 Posts
In that case, JUNK the bike.
GamblerGORD53 is offline  
Old 01-26-23, 05:38 AM
  #10  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
Originally Posted by Shadco View Post
So Ö

They used to be a giant dealer but arenít any longer. Bike Doctor in Arnold MD talk to Steve if he is in. They are a great shop.

cheers
Thanks Shad.

I just found an old school LBS (Wooden Wheels) near my office... I didn't know they were still in business. I've tried both of the big box bike stores around here and the mechanic service has been hit or miss.

If that shop can't help, I will call Bike Doctor.
Jughed is offline  
Old 01-26-23, 05:43 AM
  #11  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
Originally Posted by GamblerGORD53 View Post
In that case, JUNK the bike.
The nearest LBS said the same thing. They wouldn't even look at the bike - they said "carbon fiber in a crash, throw it in the trash".

Easier said than done... these items are quite expensive as we all know.

And I just can't fathom that a purpose built Cyclocross frame would be trash after a crash.

People would be throwing bikes away multiple times per season... maybe they do?
Jughed is offline  
Old 01-26-23, 08:29 AM
  #12  
Crankycrank
Senior Member
 
Join Date: Jan 2009
Location: San Diego, CA
Posts: 3,239
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 709 Post(s)
Liked 743 Times in 548 Posts
Originally Posted by Jughed View Post
The nearest LBS said the same thing. They wouldn't even look at the bike - they said "carbon fiber in a crash, throw it in the trash".
The best thing about CF is that most damage can be repaired, sometimes even by the home mechanic doing it the first time. It just depends on what the damage is. If no luck with bike shops look for CF repair specialists if you don't feel comfortable doing this yourself and as mentioned above you may be able to buy one of the thread restorer options you could do yourself. Posting photos of the mount would be helpful as well.

Last edited by Crankycrank; 01-26-23 at 08:33 AM.
Crankycrank is offline  
Old 01-26-23, 08:46 AM
  #13  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
Originally Posted by Crankycrank View Post
The best thing about CF is that most damage can be repaired, sometimes even by the home mechanic doing it the first time. It just depends on what the damage is. If no luck with bike shops look for CF repair specialists if you don't feel comfortable doing this yourself and as mentioned above you may be able to buy one of the thread restorer options you could do yourself. Posting photos of the mount would be helpful as well.
Thanks - there is no damage to the CF, just a stripped thread that may or may not have happened during the crash.

And, I've got about 1000 miles on the bike since the crash - mostly dead flat gravel roads. The structure is of the bike fine. I just don't use the front brake. I want to get the bike ready for some real gravel races in the mountains this summer... a front brake would be nice for that.

I will try to get a picture at some point.
Jughed is offline  
Old 01-26-23, 09:15 AM
  #14  
pdlamb
Senior Member
 
Join Date: Dec 2010
Location: northern Deep South
Posts: 8,120

Bikes: Fuji Touring, Novara Randonee

Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 2195 Post(s)
Liked 1,435 Times in 908 Posts
I was curious just how easy it would be to find a pro to fix it, so I typed "carbon fiber bike repair maryland" and the helpful search engine appended "lottery."

I don't know that the odds are stacked against you that badly. But I personally wouldn't think about riding that bike in mountainous terrain where I needed a front brake before I had a specialist look at the fork (at a minimum) or the entire frame (better) and give me the OK to ride it.

If you've got a good ear and a quiet place to work, you could try the coin tap inspection. Tap the frame and fork with a dime, spacing the taps by the diameter of that time. Cover the entire frame. Any place where the normal click comes back as a thud is suspect.

If you can't afford to replace the frame (or the bike), how do you expect to pay the medical bills when the frame fails and you crash?
pdlamb is offline  
Old 01-26-23, 09:41 AM
  #15  
Jughed
Junior Member
Thread Starter
 
Join Date: Jan 2023
Location: Eastern Shore MD
Posts: 150

Bikes: Trek ALR/Giant TCX/Sette CX1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 118 Times in 55 Posts
Originally Posted by pdlamb View Post
I was curious just how easy it would be to find a pro to fix it, so I typed "carbon fiber bike repair maryland" and the helpful search engine appended "lottery."

I don't know that the odds are stacked against you that badly. But I personally wouldn't think about riding that bike in mountainous terrain where I needed a front brake before I had a specialist look at the fork (at a minimum) or the entire frame (better) and give me the OK to ride it.

If you've got a good ear and a quiet place to work, you could try the coin tap inspection. Tap the frame and fork with a dime, spacing the taps by the diameter of that time. Cover the entire frame. Any place where the normal click comes back as a thud is suspect.

If you can't afford to replace the frame (or the bike), how do you expect to pay the medical bills when the frame fails and you crash?
The frame is OK. It's been coin tapped. It was inspected by Giant. It was inspected at my local Trek shop - but they will not sign off on any CF bike that was in a crash, but they said the frame was not damaged.

It's just a thread issue. An issue with the metal insert in the CF fork.
Jughed is offline  
Old 01-26-23, 09:53 AM
  #16  
squirtdad
Senior Member
 
squirtdad's Avatar
 
Join Date: Jul 2006
Location: San Jose (Willow Glen) Ca
Posts: 9,049

Bikes: 85 team Miyata (modern 5800 105) , '84 Team Miyata,(dura ace old school) 80?? SR Semi-Pro 600 Arabesque

Mentioned: 94 Post(s)
Tagged: 0 Thread(s)
Quoted: 1940 Post(s)
Liked 1,857 Times in 1,092 Posts
posting a picture will help.

calfee is well known for carbon repair https://calfeedesign.com/carbon-repair/

call them, if they won't take it on, time for a new fork
__________________
Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or whole biked 57,58)


squirtdad is offline  
Old 01-26-23, 10:46 AM
  #17  
base2 
Doesn't brain good.
 
base2's Avatar
 
Join Date: Jun 2015
Location: Pacific Northwest
Posts: 2,464

Bikes: 5 good ones, and the occasional project.

Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1360 Post(s)
Liked 1,094 Times in 627 Posts
I read his "story" as consistent. A previous shop mechanic or owner overtightened the caliper bolt & it held until the OP messed with it & the insert threads came out with the bolt.

This is why thread compound, torque tools are used & anything other than IS mount sucks. (Don't get me started on thru-axle.)

OP: This would be a good excuse for a fork upgrade. Ritchey WCS or Whiskey make suitable forks that probably weigh less than your current OEM fork.

Last edited by base2; 01-26-23 at 11:31 AM.
base2 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 or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.