Is a dirty chain a drag?
#1
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Is a dirty chain a drag?
Well, actually, no. At least according to Ceramic Speed and GCN
The TL;DR version: A fairly filthy chain adds about 1 watt of drag over a clean new chain. Simulated rain adds around 0.5 watts. It would have been interesting to see what would happen with an unlubricated chain.
Bottom line, it seems that all the murdered electrons over chain lubrication have died in vain.
The TL;DR version: A fairly filthy chain adds about 1 watt of drag over a clean new chain. Simulated rain adds around 0.5 watts. It would have been interesting to see what would happen with an unlubricated chain.
Bottom line, it seems that all the murdered electrons over chain lubrication have died in vain.
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Plan Epsilon Around Lake Michigan in the era of Covid
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Solo Without Pie. The search for pie in the Midwest.
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Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
#3
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Surprised me! I've always kept chains clean and well-lubed, figuring it was lots more efficient. Will continue to do so, to slow down wear, but how little difference being clean makes caught me off guard.
#4
After all this time I wasn't going to start worrying, my experience has shown that a mucky oily chain is still doing the business. Obviously there are limits - excessive muck is unseemly, and chain cleaning is still good for those days you don't feel like fighting the weather, or if you have a sore knee.
#5
Old fart



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While a dirty chain may not significantly increase "drag," it does contribute to drivetrain wear. Keep it clean, and your drivetrain components will last much longer.
#6
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I’m not advocating for riding around with dirty chains. There are other reasons not to do that but obsessing over chain and drivetrain cleanliness is a fool’s errand.
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Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
#7
Facts just confuse people




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I never thought a dirty chain was a big drag on my power. The only reasonable reasons to me for keeping a clean chain is aesthetics. And not getting a black mark on my calf or socks that is hard to clean off. Or keep me from getting gunk all over my fingers for the very rare times I might have to fix a chain drop.
#8
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Viscosity and pumping losses even with fresh clean whatever lube. Isn't Ceramic Speed selling the idea their chain lube that adds the least drag?
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#9
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I’m not sure you have the evidence to make the statement that a dirty chain increases drivetrain wear. The video shows that a dirty chain decreases power output by 1 W. The decrease is due to an increase in friction. Friction is a measure of the wear of the components. If a dirty chain significantly increases drivetrain wear, it would show in the decrease in the power output like that seen when they dropped sand onto the chain. The power output dropped in that case by 12W which is significant, although I would say that putting that much sand on a chain would be next to impossible even in the wettest ride.
I’m not advocating for riding around with dirty chains. There are other reasons not to do that but obsessing over chain and drivetrain cleanliness is a fool’s errand.
I’m not advocating for riding around with dirty chains. There are other reasons not to do that but obsessing over chain and drivetrain cleanliness is a fool’s errand.
#10
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Clean Chain, Clean Bike, Light Lube...
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Last edited by zandoval; 10-06-25 at 11:15 AM.
#11
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No. Sand is the form of dirt. Most everything else in dirt is way softer than the steel of the chain. Silicon dioxide is harder than steel.
I would also argue that their concentration of sand was much higher than would be encountered in the wild.
The used chain in the video is already fairly dirty but didn’t show much difference from a new chain.
I would also argue that their concentration of sand was much higher than would be encountered in the wild.
The used chain in the video is already fairly dirty but didn’t show much difference from a new chain.
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Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Last edited by cyccommute; 10-06-25 at 11:32 AM.
#12
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No. Sand is the form of dirt. Most everything else in dirt is way softer than the steel of the chain. Silicon dioxide is harder than steel.
I would also argue that their concentration of sand was much higher than would be encountered in the wild.
The used chain in the video is already fairly dirty but didn’t show much difference from a new chain.
I would also argue that their concentration of sand was much higher than would be encountered in the wild.
The used chain in the video is already fairly dirty but didn’t show much difference from a new chain.
again.
#14
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Nope. You are missing the point. The chain provided by the GCN guy was already contaminated with sand. That small amount of contamination only reduced the efficiency by 1 W. The water/sand demonstration applied too much sand to the chain. Even if you rode across a sand dune, you are unlikely to kick that much sand up into the chain. That part was a bad demonstration.
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Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Last edited by cyccommute; 10-06-25 at 04:58 PM.
#15
aka Tom Reingold




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And if friction and drivetrain wear are not compelling reasons to keep a chain clean, what reasons do you have?
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#17
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You have my attention. I know my perceptions can be based on expectations and not real sensations. I believe I feel the difference between a chain that is well lubricated and one that isn't. I believe I feel the difference between a new chain and a worn one. Hearing that they barely make a difference makes it sound like I've been fooling myself.
And if friction and drivetrain wear are not compelling reasons to keep a chain clean, what reasons do you have?
And if friction and drivetrain wear are not compelling reasons to keep a chain clean, what reasons do you have?

I think this chain was dirty and still well lubricated.
#18
Old fart



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I’m not sure you have the evidence to make the statement that a dirty chain increases drivetrain wear. The video shows that a dirty chain decreases power output by 1 W. The decrease is due to an increase in friction. Friction is a measure of the wear of the components. If a dirty chain significantly increases drivetrain wear, it would show in the decrease in the power output like that seen when they dropped sand onto the chain.
#19
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And your hands (and some clothes) will stay cleaner as well.
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#20
FWIW, I haven't used any chain-cleaning device in decades. When I hear a chain start to squeak, I drip some chain oil onto a plastic produce bag, grab the chain with the bag, and backpedal until it looks as if the chain is lightly coated. I wipe off the excess and ride.
That's it until the chain squeaks again, many hundreds of miles later (unless I ride in the rain at some point, which moves up the schedule.)
I'm always amazed by how long my chains last.
#21
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The 1w loss doesn’t sound like much.
Until you consider that loss is due to the addition of grinding paste, or an approximation of it.
maybe we can make this a wax vs oil thread….. again!
Barry
Until you consider that loss is due to the addition of grinding paste, or an approximation of it.
maybe we can make this a wax vs oil thread….. again!
Barry
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#22
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I will point out one thing that I didn’t see mentioned. At least it’s something I’ve taken notice of — The resultant buildup of gunk on the chain rings, gears, and derailleur pulley wheels eventually causes the chain to not seat properly on them. As such, the chain may skip, and/or not shift smoothly. — Dan
#23
aka Tom Reingold




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But arguably vanishingly minimal, as demonstrated by the tiny amount of friction loss shown in the tests. Certainly insignificant, given how slowly chains wear.
FWIW, I haven't used any chain-cleaning device in decades. When I hear a chain start to squeak, I drip some chain oil onto a plastic produce bag, grab the chain with the bag, and backpedal until it looks as if the chain is lightly coated. I wipe off the excess and ride.
That's it until the chain squeaks again, many hundreds of miles later (unless I ride in the rain at some point, which moves up the schedule.)
I'm always amazed by how long my chains last.
FWIW, I haven't used any chain-cleaning device in decades. When I hear a chain start to squeak, I drip some chain oil onto a plastic produce bag, grab the chain with the bag, and backpedal until it looks as if the chain is lightly coated. I wipe off the excess and ride.
That's it until the chain squeaks again, many hundreds of miles later (unless I ride in the rain at some point, which moves up the schedule.)
I'm always amazed by how long my chains last.
Interesting method of lubrication.
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New York City and High Falls, NY
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“When man invented the bicycle he reached the peak of his attainments.” — Elizabeth West, US author
Please email me rather than PM'ing me. Thanks.
Tom Reingold, tom@noglider.com
New York City and High Falls, NY
Blogs: The Experienced Cyclist; noglider's ride blog
“When man invented the bicycle he reached the peak of his attainments.” — Elizabeth West, US author
Please email me rather than PM'ing me. Thanks.
#24
aka Tom Reingold




Joined: Jan 2009
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From: New York, NY, and High Falls, NY, USA
Bikes: 1962 Rudge Sports, 1971 Raleigh Super Course, 1971 Raleigh Pro Track, 1974 Raleigh International, 1975 Viscount Fixie, 1982 McLean, 1996 Lemond (Ti), 2002 Burley Zydeco tandem
I will point out one thing that I didn’t see mentioned. At least it’s something I’ve taken notice of — The resultant buildup of gunk on the chain rings, gears, and derailleur pulley wheels eventually causes the chain to not seat properly on them. As such, the chain may skip, and/or not shift smoothly. — Dan
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Tom Reingold, tom@noglider.com
New York City and High Falls, NY
Blogs: The Experienced Cyclist; noglider's ride blog
“When man invented the bicycle he reached the peak of his attainments.” — Elizabeth West, US author
Please email me rather than PM'ing me. Thanks.
Tom Reingold, tom@noglider.com
New York City and High Falls, NY
Blogs: The Experienced Cyclist; noglider's ride blog
“When man invented the bicycle he reached the peak of his attainments.” — Elizabeth West, US author
Please email me rather than PM'ing me. Thanks.
#25
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interesting factoid. what percentage is 1 W of an average person's effort? I kinda feel like I remember my bike working better / easier after cleaning the drivetrain, especially a particularly filthy chain
is 1 W noticeable?
is 1 W noticeable?




