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

Tooth wear on chainrings - after 85 miles?

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.

Tooth wear on chainrings - after 85 miles?

Reply

Old 08-24-03, 08:35 AM
  #1  
mightypudge
Victim of Circumstance
Thread Starter
 
mightypudge's Avatar
 
Join Date: Jun 2003
Location: Philadelphia, PA
Posts: 337
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Tooth wear on chainrings - after 85 miles?

During my ride yesterday, one of the teeth on my middle chainring bent inward. When I got home I was able to use a pair of pliers to bend it back into place. No big deal.

After I cleaned the bike I inspected all three chainrings and noticed many of the teeth on all three chainring are already showing a lot of wear. Some of the teeth appear to already be worn into points. I only have 85 miles on the bike so far, and I can't imagine Cannondale would use cheap chainrings on a $1800 bike (or, would they?).

Is this kind of wear normal? What are my choices for better quality chainrings?
mightypudge is offline  
Reply With Quote
Old 08-24-03, 08:42 AM
  #2  
DnvrFox
Banned.
 
DnvrFox's Avatar
 
Join Date: Aug 2001
Posts: 20,917
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally posted by mightypudge
During my ride yesterday, one of the teeth on my middle chainring bent inward. When I got home I was able to use a pair of pliers to bend it back into place. No big deal.

After I cleaned the bike I inspected all three chainrings and noticed many of the teeth on all three chainring are already showing a lot of wear. Some of the teeth appear to already be worn into points. I only have 85 miles on the bike so far, and I can't imagine Cannondale would use cheap chainrings on a $1800 bike (or, would they?).

Is this kind of wear normal? What are my choices for better quality chainrings?
Chain rings use different size and differently facing teeth to assist in shifting. The tooth you bent "back" was probably designed the way it was. Be careful in messing with that stuff.
DnvrFox is offline  
Reply With Quote
Old 08-24-03, 11:32 AM
  #3  
sch
Senior Member
 
Join Date: May 2003
Location: Mountain Brook. AL
Posts: 3,499
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 167 Post(s)
You have discovered one of the major innovations of the '80s: tooth shape, along with those little curved and ramped cutouts on the inside of the middle
and large chainrings greatly facilitate shifting by picking up the chain faster and allowing it to be inserted on to the chainring before it is fully lined up. A brief look at a new bike will show the different tooth shapes are present when new.
The alloy chainrings are made of is good for 8-20kmiles of riding on the road.
Mud bugs get shorter life spans. Steve
sch is offline  
Reply With Quote
Old 08-24-03, 12:01 PM
  #4  
Dave Stohler
60mph in the 42 ring!
 
Dave Stohler's Avatar
 
Join Date: Jul 2003
Location: Niagara Frontier, NY
Posts: 546
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Yeah, you probably just ruined a perfectly good $50 chainring. When it doesn't shift right next time you ride, go down to the LBS and buy yourself a new one.
Dave Stohler is offline  
Reply With Quote
Old 08-24-03, 12:51 PM
  #5  
miamijim
Senior Member
 
miamijim's Avatar
 
Join Date: Aug 2003
Location: Tampa, Florida
Posts: 13,917
Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 321 Post(s)
I dont think you ruined the chainring. A few good firm shifts might put it back in its proper place. Would Cannondale use cheap chainrings? Hell yea they would. Unless your chainrings are forged they are cheap. I would never buy any rings other than genuine Shimanos. They are expensive for a reason. Most 'house brand' parts are cheap, thats why they use them.
miamijim is offline  
Reply With Quote
Old 08-24-03, 05:25 PM
  #6  
mightypudge
Victim of Circumstance
Thread Starter
 
mightypudge's Avatar
 
Join Date: Jun 2003
Location: Philadelphia, PA
Posts: 337
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally posted by Dave Stohler
Yeah, you probably just ruined a perfectly good $50 chainring. When it doesn't shift right next time you ride, go down to the LBS and buy yourself a new one.
According to the bike shop where I work, also a Cannondale dealer, the chainrings on the Scalpel 800 are sort of cheap from the factory. Most times they recommend that serious riders upgrade the crank or chainrings to something more sturdy.

The service manager at my shop checked out my ring today and I did *not* bend back the shifting tooth. When I explained what was happening yesterday he told me he would done the same thing. He also completely checked the drivetrain over to make sure it was shifting OK, which it was.

Last edited by mightypudge; 08-24-03 at 05:56 PM.
mightypudge is offline  
Reply With Quote
Old 08-24-03, 05:31 PM
  #7  
mightypudge
Victim of Circumstance
Thread Starter
 
mightypudge's Avatar
 
Join Date: Jun 2003
Location: Philadelphia, PA
Posts: 337
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally posted by DnvrFox
Chain rings use different size and differently facing teeth to assist in shifting. The tooth you bent "back" was probably designed the way it was. Be careful in messing with that stuff.
I was very careful to not bend back the wrong tooth. I checked out all three wheels and identifed the shifting point so that I knew I was doing the right thing.

What was happening yesterday on my ride was that at every revolution of the crank, my chain would try shifting from the middle to the small chainring. Of course it wouldn't make it because the derailleur was still in place, so it would jump back. This caused a skip in the revolution that made me hop off the bike to inspect it.

It happened when I shifted to the large chainring and simultaneously stood up to climb. I figured I'd gotten up to early and bent the tooth during the shift. The service manager at my shop said that sounds very likely.

Once again, thanks doe the tip. I'm probably going to pickup a new chainring set anyway, but it's good to know I was able to fix the current ring.
mightypudge is offline  
Reply With Quote
Old 08-24-03, 05:33 PM
  #8  
mightypudge
Victim of Circumstance
Thread Starter
 
mightypudge's Avatar
 
Join Date: Jun 2003
Location: Philadelphia, PA
Posts: 337
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally posted by miamijim
I dont think you ruined the chainring. A few good firm shifts might put it back in its proper place. Would Cannondale use cheap chainrings? Hell yea they would. Unless your chainrings are forged they are cheap. I would never buy any rings other than genuine Shimanos. They are expensive for a reason. Most 'house brand' parts are cheap, thats why they use them.
I'm pretty much in agreement there. Besides Shimano, would you recommend another brand? I was looking at stuff from TruVativ and Race Face. With my employee discount taking effect shortly it makes sense to go for the gusto.
mightypudge is offline  
Reply With Quote
Old 08-24-03, 05:45 PM
  #9  
DnvrFox
Banned.
 
DnvrFox's Avatar
 
Join Date: Aug 2001
Posts: 20,917
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It happened when I shifted to the large chainring and simultaneously stood up to climb. I figured I'd gotten up to early and bent the tooth during the shift. The service manager at my shop said that sounds very likely.
Wow, a pretty bad chain ring.

Your first post gave no hint that you knew what you were doing, which is why you probably got so many responses from folks who thought you did not know.
DnvrFox is offline  
Reply With Quote
Old 08-24-03, 05:55 PM
  #10  
mightypudge
Victim of Circumstance
Thread Starter
 
mightypudge's Avatar
 
Join Date: Jun 2003
Location: Philadelphia, PA
Posts: 337
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally posted by DnvrFox
Wow, a pretty bad chain ring.
My thoughts exactly.

Originally posted by DnvrFox
Your first post gave no hint that you knew what you were doing, which is why you probably got so many responses from folks who thought you did not know.
My fault. I apologize.
mightypudge is offline  
Reply With Quote
Old 08-29-03, 07:31 PM
  #11  
TrekRider
Senior Member
 
Join Date: Jul 2003
Location: Gambrills, Maryland
Posts: 2,717
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I bet you haven't been flossing after every ride have you?

TrekRider is offline  
Reply With Quote
Old 08-29-03, 10:48 PM
  #12  
Dannihilator
User Title
 
Dannihilator's Avatar
 
Join Date: Oct 2002
Location: Annandale, New Jersey
Posts: 19,607

Bikes: 2008 Trek Portland, 1989 Nishiki Altron

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 107 Post(s)
Race Face makes some downright indestructable chainrings.
__________________
Appreciate the old bikes more than the new.
Dannihilator is offline  
Reply With Quote
Old 08-30-03, 04:18 AM
  #13  
MichaelW
Senior Member
 
Join Date: Feb 2001
Location: England
Posts: 12,952
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
The best 3rd party chainrings are probably Specialities-TA. They are available in any tooth count for any crank pattern, as individual rings or matched sets, with all the usual ramps and pins.
A lot of professional teams use TA rings on their Campy or Shimano cranks.
MichaelW is offline  
Reply With Quote
Old 08-31-03, 07:21 PM
  #14  
skdsl
7 inch Weagle
 
skdsl's Avatar
 
Join Date: Jan 2003
Location: Townsville NQ Australia
Posts: 185
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I bought some Deore cranks almost two months ago, and upgraded the middle ring to an alloy one which I was told was LX/XT quality. I have done a little over 700km on them and the middle ring is toast. I was a little dissapointed to say the least. It had worn to a stage where the front of the teeth had mushroomed out and under high pedalling load it would throw the chain off the middle ring, and I would smash my knees into the headstem. I replaced the chain just after I got the cranks, and it is still OK now. The teeth that showed the most wear were the thin ones with shifting ramps, so if I destroy this one too quickly, I may have to use a DH middle ring without the shifting ramps.
skdsl is offline  
Reply With Quote
Old 08-31-03, 08:15 PM
  #15  
VO2 MAX
Junior Member
 
Join Date: Aug 2003
Location: NEWCASTLE, AUSTRALIA
Posts: 24
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
dont mess with stuff u dont understand, would be my advise. If it was a new bike, take it back to the shop.
VO2 MAX is offline  
Reply With Quote
Old 09-01-03, 06:32 AM
  #16  
Richard D
Donating member
 
Richard D's Avatar
 
Join Date: Sep 2001
Location: Faversham, Kent, UK
Posts: 1,852
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally posted by skdsl
I bought some Deore cranks almost two months ago, and upgraded the middle ring to an alloy one which I was told was LX/XT quality. I have done a little over 700km on them and the middle ring is toast. I was a little dissapointed to say the least. It had worn to a stage where the front of the teeth had mushroomed out and under high pedalling load it would throw the chain off the middle ring, and I would smash my knees into the headstem. I replaced the chain just after I got the cranks, and it is still OK now. The teeth that showed the most wear were the thin ones with shifting ramps, so if I destroy this one too quickly, I may have to use a DH middle ring without the shifting ramps.
As far as I'm aware the cheaper Shimano Steel rings last considerably longer than their alloy rings, but you do have the weight issue to consider.

Richard
__________________
Currently riding an MTB with a split personality - commuting, touring, riding for the sake of riding, on or off road :)
Richard D is offline  
Reply With Quote

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