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 05-21-11, 09:33 PM   #1
mrund3rd09
Senior Member
Thread Starter
 
Join Date: Apr 2011
Location: iowa
Bikes:
Posts: 156
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
how to measure wear on gears

I bought an '84 Fuji Del Rey. The chain was stretched by 1/16-1/8, and had to replaced. the cogset was also replaced. the front gears are still the old ones, and I'm wondering if I need to replace those as well.

When I pedal, I can hear the chain clicking with the gears. I've lubed up the chain pretty good, and it's still doing that.
mrund3rd09 is offline   Reply With Quote
Old 05-21-11, 09:42 PM   #2
FastJake
Constant tinkerer
 
FastJake's Avatar
 
Join Date: May 2010
Location: Madison, Wisconsin
Bikes:
Posts: 7,577
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Chainrings usually last pretty long. I've never actually had a problem with one, despite all the old bikes I ride. Can you post a picture of them? Are you sure the clicking is coming from the front?
FastJake is offline   Reply With Quote
Old 05-21-11, 09:47 PM   #3
Kimmo
bike whisperer
 
Kimmo's Avatar
 
Join Date: Dec 2009
Location: Melbourne, Oz
Bikes: copy/paste links: http://velospace.org/node/36949 http://velospace.org/node/47746 http://velospace.org/node/47747
Posts: 7,099
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
What kind of clicking? The quiet whir of the chain wrapping around your jockey wheels, or the horrible clatter of the chain catching on larger cogs, for instance?

IME worn chainrings produce a throbby feeling through the pedals under power; the teeth have a shark-fin look. Post a pic of your rings.
Kimmo is offline   Reply With Quote
Old 05-21-11, 09:50 PM   #4
Shimagnolo
Senior Member
 
Shimagnolo's Avatar
 
Join Date: May 2008
Location: Zang's Spur, CO
Bikes:
Posts: 7,517
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 145 Post(s)
I had a bike I used for years as a commuter.
The steel chainrings were worn to a sharks-tooth shape, but still worked w/o problem when I finally junked the bike.
I've never replaced a chainring due to wear.
Shimagnolo is offline   Reply With Quote
Old 05-21-11, 09:56 PM   #5
Kimmo
bike whisperer
 
Kimmo's Avatar
 
Join Date: Dec 2009
Location: Melbourne, Oz
Bikes: copy/paste links: http://velospace.org/node/36949 http://velospace.org/node/47746 http://velospace.org/node/47747
Posts: 7,099
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'd hazard a guess steel and ally rings are apples and oranges.

As far as I can figure, a chainring can wear and wear and it's not a problem until either the teeth have enough of a hook to cause friction as the rollers are dragged over them, or the effective diameter of the chainring is reduced enough to space the pins too close. Chain wear could potentially mask the former effect, and I'm pretty sure I've noticed a ring I previously thought was still okay throb with a new chain.

Last edited by Kimmo; 05-21-11 at 10:03 PM.
Kimmo is offline   Reply With Quote
Old 05-21-11, 10:14 PM   #6
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Rock Springs, WY
Bikes: My War
Posts: 26,716
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 217 Post(s)
I've had increased chain suck on worn MTB rings. I've got a couple of completely wasted inner road rings that never caused me any problem though. But, you can tell they're wasted when the teeth get asymmetrical.

Oh, I remember reading about techniques for figuring chainring wear based on how far you could pull the chain away from the ring. Forget exactly how that went and it seemed pretty vague at the time, though.

Last edited by LesterOfPuppets; 05-21-11 at 10:19 PM.
LesterOfPuppets is online now   Reply With Quote
Old 05-21-11, 10:20 PM   #7
Kimmo
bike whisperer
 
Kimmo's Avatar
 
Join Date: Dec 2009
Location: Melbourne, Oz
Bikes: copy/paste links: http://velospace.org/node/36949 http://velospace.org/node/47746 http://velospace.org/node/47747
Posts: 7,099
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by LesterOfPuppets View Post
Oh, I remember reading about techniques for figuring chainring wear based on how far you could pull the chain away from the ring. Forget exactly how that went and it seemed pretty vague at the time, though.
With a fresh chain, that would indicate the effective reduction of the chainring diameter. Prolly want to see how far you can pull a new chain from a new ring before inferring much from it, though.
Kimmo 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 09:54 PM.