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 02-14-10, 11:57 PM   #1
Cyclosomatic
Junior Member
Thread Starter
 
Cyclosomatic's Avatar
 
Join Date: Sep 2009
Location: Santa Cruz, CA
Bikes:
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Uh-Oh, bent chainstay...

So i finally got around to throwing some disk breaks on my SS, when much to my chagrin i discovered my disk-side chain stay has a dent that appears to have changed its dimensions just enough to (maybe, just maybe) interfere with the disk. What can i do? My frame is chromoly, is there any chance i could have it bent back?
Cyclosomatic is offline   Reply With Quote
Old 02-15-10, 12:01 AM   #2
AEO
Senior Member
 
AEO's Avatar
 
Join Date: Jun 2007
Location: A Coffin Called Earth. or Toronto, ON
Bikes: Bianchi, Miyata, Dahon, Rossin
Posts: 12,258
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
pics would be helpful.
__________________
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
http://sanfrancisco.ibtimes.com/arti...ger-photos.htm
AEO is offline   Reply With Quote
Old 02-15-10, 01:05 AM   #3
Cyclosomatic
Junior Member
Thread Starter
 
Cyclosomatic's Avatar
 
Join Date: Sep 2009
Location: Santa Cruz, CA
Bikes:
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
aaallllllright, that was a little more work than it should have been but here's some evidence...
http://i51.photobucket.com/albums/f3...n/P1000637.jpg
http://i51.photobucket.com/albums/f3...n/P1000640.jpg
http://i51.photobucket.com/albums/f3...n/P1000641.jpg
http://i51.photobucket.com/albums/f3...n/P1000646.jpg
& I apologize for how difficult it is to see, but flashes and dirty, glossy black paint don't mix.
Cyclosomatic is offline   Reply With Quote
Old 02-15-10, 01:37 AM   #4
dabac
Senior Member
 
Join Date: Mar 2008
Bikes:
Posts: 5,694
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 97 Post(s)
Quote:
Originally Posted by Cyclosomatic View Post
...my disk-side chain stay has a dent that appears to have changed its dimensions just enough to (maybe, just maybe) interfere with the disk. What can i do? My frame is chromoly, is there any chance i could have it bent back?
Well, Cr-Mo can be immensely forgiving, and undoubtely there are frames more messed up than that that keeps on delivering good service.
And WRT to brake rotor clearance(if it is an issue) it shouldn't be too much of a problem bending it back. Getting it all in alignment can be another issue though.
But if it was me I'd worry about the seemingly very sharp crease at the bottom of the dent.
I can't think of any way to get that one out. Either it'll act as a stress riser for later fatigue failure, or it'll act like scribe mark for the chain stay to fold right there next time the bike sees some rough handling.
dabac is online now   Reply With Quote
Old 02-15-10, 02:27 AM   #5
BCRider
Senior Member
 
BCRider's Avatar
 
Join Date: Mar 2008
Location: The 'Wack, BC, Canada
Bikes: Norco (2), Miyata, Canondale, Soma, Redline
Posts: 5,456
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
My own thoughts are that while it may not have been an issue when the bike was stopped with rim brakes that when relying on disc brakes that will put more stress into both the seat and chain stays on that side that the forces acting on this kink will have more effect on the damaged area. By all means straighten it out. But at the same time keep a frequent and close eye on that damaged area for stress cracks or further deformation caused by that damage.
BCRider is offline   Reply With Quote
Old 02-15-10, 10:33 AM   #6
davidad
Senior Member
 
Join Date: Feb 2009
Bikes:
Posts: 4,950
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Straighten it. Be aware that there is now a stress riser and that it will eventually break. Being steel there will be ample warning so you will just need to keep an eye on it.
davidad is offline   Reply With Quote
Old 02-15-10, 10:01 PM   #7
Cyclosomatic
Junior Member
Thread Starter
 
Cyclosomatic's Avatar
 
Join Date: Sep 2009
Location: Santa Cruz, CA
Bikes:
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
yeah... thats kind of what i was afraid of. dropped it off @ the LBS a few hours ago to see if they could help me out, i'll find out tomorrow. but thanks for the help.
Cyclosomatic is offline   Reply With Quote
Old 02-15-10, 11:14 PM   #8
BCRider
Senior Member
 
BCRider's Avatar
 
Join Date: Mar 2008
Location: The 'Wack, BC, Canada
Bikes: Norco (2), Miyata, Canondale, Soma, Redline
Posts: 5,456
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
They'll almost certainly tell you that it is toast, dead meat on a stick, bereft of life, gone to meet its maker, it is an ex-frame. Liability will suggest that and common sense about that amount of damage will support it.

I'd say it's time to start shopping for a new frame. I know that rear end failures are not as epic as front end ones but I would not trust that frame to haul my butt around the block anymore let alone across town or down some trail in the middle of nowhere.
BCRider 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 05:18 AM.