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

Bent middle chainring tooth

Search
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.

Bent middle chainring tooth

Thread Tools
 
Search this Thread
 
Old 05-28-23 | 11:34 AM
  #1  
Thread Starter
Newbie
 
Joined: May 2023
Posts: 2
Likes: 2
Bent middle chainring tooth

I have noticed a bent over tooth on the middle chainring of my 1999 specialised rockhopper mtb and wondered whether it is supposed to be like this for chain pick up purposes ? Otherwise I will attempt to straighten it as it seems to be causing interference in the lower gears - in the smallest chainring and higher rear sprocket gears a clicking and causing of a jumping sensation whilst peddling . Does anyone have any ideas ? Thanks
fieldspring is offline  
Reply
Old 05-28-23 | 12:48 PM
  #2  
soyabean's Avatar
Senior Member
 
Joined: Feb 2022
Posts: 1,027
Likes: 467
From: GMT-5
It prolly rolled over a curb, I see it all the time.

Vise grip and eyeball it.
soyabean is offline  
Reply
Old 05-28-23 | 06:08 PM
  #3  
Andrew R Stewart's Avatar
Senior Member
Titanium Club Membership
10 Anniversary
 
Joined: Feb 2012
Posts: 19,373
Likes: 5,515
From: Rochester, NY

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB

Except I prefer an adjustable wrench if it can fit. Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Reply
Old 05-28-23 | 06:14 PM
  #4  
Bill Kapaun's Avatar
Really Old Senior Member
15 Anniversary
Community Builder
 
Joined: Feb 2007
Posts: 14,667
Likes: 1,904
From: Mid Willamette Valley, Orygun

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds. 2019 Giant Explore E+3

IF it's a "shift aid", they'll typically be "several", evenly spaced around the circumference of the ring.
Bill Kapaun is offline  
Reply
Old 05-28-23 | 06:25 PM
  #5  
alcjphil's Avatar
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 6,655
Likes: 2,253
From: Montreal, Quebec
It would be vanishingly rare for a tooth on a middle chainring to be bent. Teeth on big chainrings often hit things as you ride over obstacles however
alcjphil is offline  
Reply
Old 05-28-23 | 06:26 PM
  #6  
Andrew R Stewart's Avatar
Senior Member
Titanium Club Membership
10 Anniversary
 
Joined: Feb 2012
Posts: 19,373
Likes: 5,515
From: Rochester, NY

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB

Agreed. I can't count the "broken off teeth tops" I have fixed over the phone with a customer Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Reply
Old 05-28-23 | 08:49 PM
  #7  
soyabean's Avatar
Senior Member
 
Joined: Feb 2022
Posts: 1,027
Likes: 467
From: GMT-5
Originally Posted by alcjphil
It would be vanishingly rare for a tooth on a middle chainring to be bent.
Wanna bet?
soyabean is offline  
Reply
Old 05-29-23 | 06:23 AM
  #8  
JohnDThompson's Avatar
Old fart
Titanium Club Membership
20 Anniversary
Community Builder
 
Joined: Nov 2004
Posts: 26,402
Likes: 5,333
From: Appleton WI

Bikes: Several, mostly not name brands.

Originally Posted by soyabean
It prolly rolled over a curb, I see it all the time.
Unlikely on a middle ring, at least without damaging teeth on the outer ring as well.

Vise grip and eyeball it.
That usually works, and if it doesn't, you're really no worse off.
JohnDThompson is offline  
Reply
Old 06-01-23 | 12:54 PM
  #9  
soyabean's Avatar
Senior Member
 
Joined: Feb 2022
Posts: 1,027
Likes: 467
From: GMT-5
Why does everyone think curbs are perfect with straight edges?

And for those that didn't know, rocks in the park are also just as imperfect.
soyabean is offline  
Reply
Old 06-02-23 | 08:38 AM
  #10  
Senior Member
 
Joined: Sep 2021
Posts: 1,596
Likes: 865
From: SW Florida, USA

Bikes: Yes

Originally Posted by soyabean
Why does everyone think curbs are perfect with straight edges?

And for those that didn't know, rocks in the park are also just as imperfect.
"Unlikely" doesn't mean "impossible". But since the typical chainring spacing is about 5mm - and the large chainring protrudes farther towards the ground and is outboard - it would almost certainly take an incident involving relatively unusual geometry to damage a single tooth on the middle chainring without also damaging the large chainring next to it.

Yeah, it could happen. But that's not a bet the proverbial "smart money" would make.
Hondo6 is offline  
Reply
Old 06-02-23 | 12:48 PM
  #11  
Thread Starter
Newbie
 
Joined: May 2023
Posts: 2
Likes: 2
Thanks

Thanks for all comments to do with bent tooth on middle chainring. I decided that it had been damaged and bent due to some incident, though we could not remember what it would have been. Took the chainrings apart and hammered the bent tooth flat and the shifting and clicking has been resolved- hoorah ! Must have been a freak accident. Just goes to show that sometimes the unlikely event can be the cause of a problem even though our rational minds are telling us otherwise.
fieldspring is offline  
Reply
Old 06-03-23 | 06:56 AM
  #12  
Senior Member
 
Joined: Jun 2020
Posts: 1,380
Likes: 537
From: Maryland

Bikes: 1982 Bianchi Sport SX, Rayleigh Tamland 1, Rans V-Rex recumbent, Fuji MTB, 80's Cannondale MTB with BBSHD ebike motor

I've bent all sorts of chainring teeth when the chain gets hung up shifting under power.

Just bend them back, replace the rings when they wear.
Pop N Wood is offline  
Reply

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.