Cog life
09-30-18 | 08:09 PM
#1
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Cog life
Hi,
I put this 16t Dura Ace cog on my bike a few days ago, and it was making some noise. Can anyone tell me if it's worn? Was trying to decide if it's just worn out and needs replacement, or if I should measure it to see if the noise was due to a difference in chainline between my old cog and this one. Thanks!
Dave
I put this 16t Dura Ace cog on my bike a few days ago, and it was making some noise. Can anyone tell me if it's worn? Was trying to decide if it's just worn out and needs replacement, or if I should measure it to see if the noise was due to a difference in chainline between my old cog and this one. Thanks!
Dave
09-30-18 | 08:16 PM
#2
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From: PHL
Bikes: Litespeed Catalyst, IRO Rob Roy, All City Big Block
It looks fine. Some cogs run a little more noisy than others. You could switch it out for something else if the noise bothers you, but I'd just make sure the whole drivetrain is clean and chain is lubed, and not worry about it. You're never going to have a silent drivetrain for very long.
09-30-18 | 08:23 PM
#3
aire díthrub
Joined: Sep 2017
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From: chatham-savannah
Bikes: Raleigh Competition, Pashley Roadster Sovereign, Mercian Vincitore Speciale
If you can’t see a difference in your chainline without breaking out the callipers to measure it, then there’s really no chance that your chainline is the issue. Dura ace cogs are designed for racing. The tooth shape/profile, is designed for strength and positive engagement under heavy torque load. Some cogs are designed with smoother, rounder teeth profiles. My guess is this what’s causing the noise you’re hearing and I would guess it will get quieter over time. From what I can see in the photo, the teeth look fine. But if you’re asking if it’s worn, am I to assume you bought a used cog?
Last edited by seamuis; 09-30-18 at 08:27 PM.
09-30-18 | 08:30 PM
#4
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It looks fine. Some cogs run a little more noisy than others. You could switch it out for something else if the noise bothers you, but I'd just make sure the whole drivetrain is clean and chain is lubed, and not worry about it. You're never going to have a silent drivetrain for very long.
Dave
09-30-18 | 08:37 PM
#5
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If you can’t see a difference in your chainline without breaking out the callipers to measure it, then there’s really no chance that your chainline is the issue. Dura ace cogs are designed for racing. The tooth shape/profile, is designed for strength and positive engagement under heavy torque load. Some cogs are designed with smoother, rounder teeth profiles. My guess is this what’s causing the noise you’re hearing and I would guess it will get quieter over time. From what I can see in the photo, the teeth look fine. But if you’re asking if it’s worn, am I to assume you bought a used cog?
The cog came from a friend. I'm running a 17t now, and wanted to try a 16 T. Its got some miles on it, but I found out the 16 T could fit on one side, and I can run a 17t freewheel without changing the chain length. Going to take this thing for a good spin!
Dave
09-30-18 | 08:59 PM
#7
aire díthrub
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From: chatham-savannah
Bikes: Raleigh Competition, Pashley Roadster Sovereign, Mercian Vincitore Speciale
I'll have to put the cog back on and really check out the chainline to see if there's a visible difference. Thanks for the background on the DA, almost sounds like its part of the design.
The cog came from a friend. I'm running a 17t now, and wanted to try a 16 T. Its got some miles on it, but I found out the 16 T could fit on one side, and I can run a 17t freewheel without changing the chain length. Going to take this thing for a good spin!
Dave
The cog came from a friend. I'm running a 17t now, and wanted to try a 16 T. Its got some miles on it, but I found out the 16 T could fit on one side, and I can run a 17t freewheel without changing the chain length. Going to take this thing for a good spin!
Dave
09-30-18 | 10:46 PM
#8
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That cog looks like it has very little wear. I'm curious how the back of it looks, are the teeth silver from the black coating wearing off?
Despite the cog being used, it could just be that the cog is less worn than your chain and the tiny difference in spacing is making the noise. Most times when you introduce a new part (cog, chain or chainring) there is a break-in period where there will be some noise, but it'll quiet down after you put in some miles.
Despite the cog being used, it could just be that the cog is less worn than your chain and the tiny difference in spacing is making the noise. Most times when you introduce a new part (cog, chain or chainring) there is a break-in period where there will be some noise, but it'll quiet down after you put in some miles.
10-01-18 | 04:55 AM
#9
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That cog looks like it has very little wear. I'm curious how the back of it looks, are the teeth silver from the black coating wearing off?
Despite the cog being used, it could just be that the cog is less worn than your chain and the tiny difference in spacing is making the noise. Most times when you introduce a new part (cog, chain or chainring) there is a break-in period where there will be some noise, but it'll quiet down after you put in some miles.
Despite the cog being used, it could just be that the cog is less worn than your chain and the tiny difference in spacing is making the noise. Most times when you introduce a new part (cog, chain or chainring) there is a break-in period where there will be some noise, but it'll quiet down after you put in some miles.
Dave
10-01-18 | 06:47 AM
#10
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You might want to change you chain, but I have a feeling it'll still be a bit noisy in the beginning. As long as your chain line and tension is good, just need to give the parts time to mesh together and things usually quiet down.
10-01-18 | 07:16 AM
#11
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From: Ciudad de Vacas, Tejas
Bikes: 34 frames + 80 wheels
Installing a new unstretched chain should definitely help. Dura Ace cogs are not necessarily noisy, depending on the chain that is used. I have a 16T 1/8” DA cog on two of my fixed gear bikes with a SRAM PC-7X chain, and they are both nearly silent.
10-01-18 | 07:23 AM
#12
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Bikes: 80s Colnago Super/NMx, 50th Daccordi, Pinarello's, Guerciotti's, Masi NS, 90s DB/GT Mtn Bikes, 90s Colnago Master, 96 Serotta Colorado TG, 95/05 Colnago C40/C50, 06 LS TI, 08 Lemond Filmore FG SS, 12 Cervelo R3, 20/15 Surly Stragler & Steamroller
Agree, the SS chain is usually changed with a new cog. Measure your chain against new spec or chain or good one on another SS bike. The park chain wear indicator tool CC-3.2 makes this task simple and consistent.
10-01-18 | 10:46 AM
#14
aire díthrub
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From: chatham-savannah
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10-01-18 | 07:31 PM
#15
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Dave
10-01-18 | 07:48 PM
#16
aire díthrub
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From: chatham-savannah
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https://www.retro-gression.com/colle...a-ace-lockring
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