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


Go Back   > >

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.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 01-14-11, 09:51 AM   #1
Chris Chicago
Senior Member
Thread Starter
 
Chris Chicago's Avatar
 
Join Date: May 2009
Location: near north side
Bikes:
Posts: 1,169
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
front derailleur bolt snapped

Installing a nos deore dx fd last night. I was using a diy shim bc the clamp was 31.8 and the seat tube was 28.6, so I wanted to make sure i got it on tight. after tightening all i could i realized it was too low, started loosening it and the bolt snapped.

2 questions
1)was the bolt just weak or are there other reasons this happens?
2)how do I get the little nut that is somewhat embedded in the derailleur arm out?

thanks!
Chris Chicago is offline   Reply With Quote
Old 01-14-11, 10:22 AM   #2
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 29,937
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 355 Post(s)
Quote:
Originally Posted by Chris Chicago View Post
.... so I wanted to make sure i got it on tight.

You probably overtightened it
setting up the fracture. It's likely your shim was off size a bit causing you to feel you need more hold than it was designed for. Check dimensions carefully when you next install it (the shim has to be very close to 1/16") and if you feel you need more hold, use a tacking agent like the stuff 3m makes for light hold Post-it notes (comes in a stick), or carbon assembly paste.

The nut system is designed with exactly your problem in mind, just set a small punch against it through the clamp and tap it out the back. Odds you can remove what's left of the screw once it's out. You have a choice of buying an original screw, or using one made for water bottle bosses, or any stainless steel 5x.8 metric screw available at the hardware store.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.

Last edited by FBinNY; 01-14-11 at 10:30 AM.
FBinNY is offline   Reply With Quote
Old 01-14-11, 01:27 PM   #3
Chris Chicago
Senior Member
Thread Starter
 
Chris Chicago's Avatar
 
Join Date: May 2009
Location: near north side
Bikes:
Posts: 1,169
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
thanks for the info. I used an old screw driver and a book as a hammer to push it out, I will try the tacking agent tonight.
Chris Chicago is offline   Reply With Quote
Old 01-14-11, 02:18 PM   #4
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 29,937
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 355 Post(s)
Quote:
Originally Posted by Chris Chicago View Post
thanks for the info. I used an old screw driver and a book as a hammer to push it out, I will try the tacking agent tonight.
What are you going to do when all books are Kindles?
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline   Reply With Quote
Old 01-14-11, 06:54 PM   #5
pmt
Experienced
 
Join Date: Sep 2007
Bikes:
Posts: 1,010
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Quote:
Originally Posted by FBinNY View Post
What are you going to do when all books are Kindles?
Use one that's broken and out of warranty.
pmt is offline   Reply With Quote
Old 01-14-11, 07:01 PM   #6
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 29,937
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 355 Post(s)
Quote:
Originally Posted by pmt View Post
Use one that's broken and out of warranty.
yes, but they could replace War and Peace in terms of striking power.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline   Reply With Quote
Old 01-15-11, 02:40 PM   #7
Chris Chicago
Senior Member
Thread Starter
 
Chris Chicago's Avatar
 
Join Date: May 2009
Location: near north side
Bikes:
Posts: 1,169
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
the book i used, "managerial economics" sustained near fatal wounds. kindle might have come through less mangled.

i should just buy a hammer for the office
Chris Chicago is offline   Reply With Quote
Old 01-15-11, 03:37 PM   #8
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 29,937
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 355 Post(s)
Quote:
Originally Posted by Chris Chicago View Post
the book i used, "managerial economics" sustained near fatal wounds. kindle might have come through less mangled.

i should just buy a hammer for the office
Next time, go outside and find a rock.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline   Reply With Quote
Old 01-15-11, 05:15 PM   #9
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Posts: 26,735
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 140 Post(s)
Quote:
Originally Posted by FBinNY View Post
Next time, go outside and find a rock.
Or use your head.
Retro Grouch 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 06:59 AM.