How to Clean Your Chain
Dirt on your bike chain is bad news. It can:
● Increase the rate of chain wear.
● Interfere with the flexibility of individual chain links.
● Increase the wear and tear on derailleur assemblies and drivetrain cogs.
● Impair your shifting performance.
Fortunately, making your chain happy is easy to do.
Regular, On-Bike Cleanings
Before each ride, look at the entire chain by standing to the side of your bike and lifting the rear wheel off the ground. Using your free hand, rotate the closest pedal slowly backward, inspecting the individual chain links for dirt buildup, rust and/or tight links (links that do not bend easily as they pass through the rear derailleur). Check for adequate lubrication by listening for squeaks while riding. If you find either condition, your chain needs at least a spot-cleaning.
To spot-clean the chain while it's still installed on your bike, simply brush out the links with a firm brush (toothbrushes work well) and relubricate the links from time to time with a chain lubricant. Remember to wipe off excess lubricant with a clean, dry rag so that it doesn't pick up new dirt. Over-lubricating can cause as many problems as under-lubricating.
Occasional Off-Bike Cleanings
Every few months or so (more often for mountain bikes), completely remove your chain (using a chain-removal tool), brush it well and completely immerse it in a chain solvent to get rid of built-up grime that brushing can't remove. Let the chain soak until most of the dirt has been freed from the links and bushings. Dry the entire chain using a clean rag. Make sure that the solvent has completely evaporated, then relubricate the chain and re-install.
A Word on Lubricants
bike-lubricant
There are 2 important properties to chain lubricants. They must:
● Minimize the accumulation of dirt, because dirt accelerates wear.
● Be durable, because lack of lubricant also increases chain wear.
Durability is the lesser issue as you can and should lube your chain often. Oils that are specifically marketed as bicycle-chain lubricants are superior to non-bicycle-specific products. They generally contain Teflon® and are designed to repel dirt and water.
Note: Always use a cleaner and lubricant designed for bike drivetrains. REI does not recommend using WD-40 on your bike (it is a cleaner but not a lubricant.
Problems to Watch for When Cleaning
Tight Links
Chain links that don't bend smoothly as they pass through the curves of the chain path may contain tight links. To spot them, pedal your chain slowly backwards and watch as individual links pass through the tight turns of your rear derailleur.
Most tight links are caused by dirt or corrosion between link plates and can be fixed with a good cleaning, some lubrication and a little flexing back and forth. Others are the result of improper pin installation (the pin that holds the chain links together is not fully inserted through the links and rollers) or serious chain damage. Occasionally, poorly installed link pins can be worked back into position by shifting them back and forth inside their chain plates by using either a chain tool or your hands. Damaged chains should be completely replaced.
Chain Stretch
Chain wear indicator tool
As chains wear, they become longer. This is called stretch, which is a misnomer because nothing actually stretches. Chains lengthen as wear occurs between the rollers and the link pins. This creates slop or free play that leads to gear "skipping" in some cases. It also causes extra wear and tear on your chain rings and rear cog teeth.
It's much cheaper to replace a chain that it is a cog set. To check for chain wear, use a wear-indicator tool such as the one shown at right. When the prong no longer fits into the chain gap, the chain has lengthened and should be replaced.