Why should one clean a chain?

Question

I do understand that this may sound like a troll question but please bear with me.

I've always been a maniac about drive train cleanliness until I got a 11 speed bike and realized I didn't want to spend the ca$$$h on the only reusable 11 speed chain link. Cleaning with the chain on the bike is too messy for my taste. Therefore I rode ~2k miles (new bike) with only periodic lubrication (using a good lubricant). Result? Nothing obviusly bad happened. Drive train is unsightly but quiet. Shifting is impeccable. Which made me wonder why should one clean a drive train at all: the process is cumbersome and a shiny drivetrain gets messy in no time with road only use under dry conditions. So why bother at all? Is there any objective study on the effectiveness of drivetrain cleaning?

Answer 1

A lot of people are now out of the habit of doing chain cleaning beyond wipe down level.

The reason to clean thoroughly is a marginal improvement in wear life and performance. But the key word is marginal. What you get for the effort is below the threshold of what many would consider worthwhile, especially riding recreationally.

Note that the expense level of your chain is a major factor here. It takes the same amount of time to clean a $13 basic 8-speed chain as it does an $60 Campy Record 11 chain, so clearly there's more economy in maximizing the service life of the latter.

Answer 2

Answering the Question

Is there any objective study on the effectiveness of drivetrain cleaning?

The short answer is that I have not seen or done any objective studies specifically addressing the pros and cons of cleaning a bicycle drivetrain.
All of the bicycle chain studies I have seen involved clean chains. There are two examples linked at the bottom of this answer.

My thesis is that there are no studies of this type is because they are very difficult to set up, very controversial (questionable parameters), and it would be difficult to turn the results into something people could use in the real world.

Sheldon Brown "Chain Maintenance"

Chain maintenance is one of the most controversial aspects of bicycle mechanics. Chain durability is affected by riding style, gear choice, whether the bicycle is ridden in rain or snow, type of soil in the local terrain, type of lubricant, lubrication techniques, and the sizes and condition of the bicycle's sprockets. Because there are so many variables, it has not been possible to do controlled experiments under real-world conditions. As a result, everybody's advice about chain maintenance is based on anecdotal "evidence" and experience. Experts disagree on this subject, sometimes bitterly. This is sometimes considered a "religious" matter in the bicycle community, and much vituperative invective has been uttered in this regard between different schismatic cults.

The Rest of the Question
From the original post:

Drive train is unsightly but quiet. Shifting is impeccable. Which made me wonder why should one clean a drive train at all: the process is cumbersome and a shiny drivetrain gets messy in no time with road only use under dry conditions. So why bother at all?

Your criteria for success are:
- Drivetrain is quiet
- Shifting is impeccable
- Duration 2000 miles

In your experience you didn't clean your chain and it was still quiet and shifted well - so why bother cleaning a chain at all? It's a reasonable question.

Here are some reasons people might bother:

• Cleanliness, this person would say "I want a clean chain above all other considerations"
• Performance, "I want my bike to perform at it's best." Friction would be one aspect of performance.
• Appearance, "I want my bike to look good at all times"
• Durability, "I want my drivetrain to last as long as possible no matter what"
• I like working on my bike""

Usually people are looking for a "sweet spot" between two critera. For example, effort vs. improvement in durability. Others may have a complex set of criteria that change over time. The search for a sweet spot based on personal criteria is the reason an objective answer is so difficult to arrive at (as Sheldon points out).

Here are some studies that focus on reducing friction in the drivetrain.
"Chain Efficiency Testing" looks at how chain wear affects friction.

"Chain Lube Efficiency Tests" focuses on which chain lube reduced friction the most.

Answer 3

The cleaning and maintaining of a bike chain may seem pointless in and of itself. That is due to the fact that more should be done not less.Cleaning and maintaining a chain should be done along with routine maintenance of the whole bicycle. When you clean the chain you notice other issues. A tire in need of replacement or one with glass in it. You see your deraileurs needs adjustment or there is gunk caught up in the gears.

I could go on ad nauseum but you get the picture. Maintaining your chain means less chance of a breakdown on the road.

Answer 4

There are good answers here already, and it is true that some people opt to simply skip anything beyond a wipedown because of the semi-disposable nature of cheap chains, but the reality is that even if particulates cannot immediately be seen the chain picks up everything you ride through and cycles it throughout the bike with force and friction. Dry materials like sand and grit especially eat away at metallic and composite parts without much warning. Not cleaning your chain is a quick route to degrading all of the other parts of your drivetrain and reducing the overall longevity of the bike. For many riders there's no need to get to the level of a white-glove inspection, but the proper application of degreasers and lubricants are a small investment up front to protect your large investment in the long run.

Citation: My work experience in the bicycle industry.

Answer 5

The important thing to remember about chain lubrication is that you shouldn't lubricate a dirty chain. So you need to clean it every time you add lubricant. However, how much cleaning is reasonable depends on how often it needs re-lubrication and how expensive the chain is.

Old 5-part (bushing-type) chains allowed riding many thousand kilometers between re-lubrications, if using them only in dry conditions. These chains were expensive and you could get 15000 km wear life out of a chain if cleaning it very thoroughly every time you lubricate it, prior to lubrication. You can no longer find these chains.

New 4-part (bushingless) chains require re-lubrication every 800 km even in dry conditions. These chains are far less expensive than the bushing-type chains, and you can't get a good wear life out of these chains.

Because the new bushingless chains anyway wear very fast and require re-lubrication very often, it probably doesn't make sense to even attempt to fully clean a chain. Fully cleaning a chain can be done by:

• Using an on-the-bike cleaning machine and changing the detergent, as many times as required so that the lubricant no longer becomes dirty. Warning: these make a huge mess and you have the problem of disposing lots of dirty environmentally damaging detergent. Then you need to wait the chain to dry so you can't lubricate it immediately afterwards.
• Taking the chain out of the bike, removing old oil in a solvent and washing it thoroughly in a detergent. Every time after washing, you agitate the chain and see if you can get dirty black stuff out of it. If you can, washing it again and again as many times as required. When the chain is clean, you dry it on a hotplate and lubricate it.

Either way will take a lot of time, and on-the-bike cleaning machines make a huge mess and require lot of wait for the drying that you can't do on a hot plate.

The problem with this approach is that quick scrubbing with a brush and wiping with a paper towel allows you to re-lubricate a chain in 20 minutes, while a thorough cleaning and lubrication probably takes at least an hour. If needing hour of work every 800 kilometers to maybe extend your chain life a little bit, there's no sense in it. However, with the old bushing-type chains you could maybe even quadruple your chain life doing thorough maintenance only every few thousand kilometers.

So with the new chains, yes, you should clean it but only to some extent. Use a brush and a paper towel. It's still somewhat dirty after that but at least you removed most of the dirt.