October 12, 2011 on 6:00 am | In From the shop, Tech Tips | 1 Comment
By Mark Lee
The modern bicycle chain is a marvel of technology. Each link is comprised of two outer plates, two inner plates, two rollers and two pins. Each plate is chamfered and beveled to optimize shifting. The forces exerted on a chain during hard efforts are enormous and yet they last for thousands of miles IF properly maintained. Here are some basics principles of chain wear and maintenance.
A chain is designed to roll precisely between the teeth of the chainrings and sprockets. In order for this to happen, the distance between each link must be exact. When a chain comes out of the box, the distance between each pin is ½”. As the chain wears or “stretches”, the distance between the links increases and shifting deteriorates.
In this first picture we see a partially extracted pin in pristine condition. The mirror polish is what makes a new chain feel so smooth. (You can also see the specially shaped edges that improve shifting.)
This is the chain pin of a worn chain. Many things cause chain wear. As the chain pivots at every link, the metal erodes a tiny bit. Metal upon metal friction causes faster wear. A good chain lube will get in between the different chain parts and act as a friction barrier. Less friction = less chain wear. This chain was poorly maintained and there was no lube on the inside of the links.
Dust and dirt will also increase friction in a chain and rapidly accelerate chain wear. The problem many people have is that too much chain lube will attract dust and dirt. So the benefits of the chain lube are offset by the increased crud on their chain.
Some points about chain maintenance:
1) Some people will use a degreaser to remove the factory lubrication from a new chain and replace it with what they think is a “better” lube. What they don’t realize is that these chain parts are actually coated in a special grease before being assembled into a chain. Here is a picture of the guts of a new chain. You can see that there is grease even in the innermost parts of the chain. This original lubricant is the best for breaking in a new chain. If you want to take the excess grease off the outside of the chain, just take a rag soaked in degreaser and run the chain through it. But there is no need to degrease a brand new chain.
2) We often see bikes come in with black chain lube specks all over the rear of the bike. The chain is wet to the touch and jet black. If you run your fingers through the sludge on the chain it will be slippery but it will also feel gritty. Too much lube! The oil slick on the chain attracts dirt and the dirt gets sucked into the chain parts and your chain wears out much sooner than it should. Its like pouring sand into your car engine.
3) We are often asked, “How many miles should I go before I lube my chain?” Well, that’s an impossible question to answer. Different riding styles, riding conditions, types of lube, and cleaning are all factors in how long a chain lube will last before needing to be refreshed. The best solution is to listen to your chain as you’re pedaling. A new chain or newly lubed chain should be fairly silent. As soon as chain noise becomes apparent its time for some lube.
4) The other most often asked question regarding chains is “What is the best chain lube?” The short answer is that which lube you use isn’t as important as how you use it. At the moment, our service shop is using Dumande Original, Dumande Bio, and I’ve just begun testing Dumande Lite. My previous favorite was TriFlow, another good all around lube. There are many more out there and each particular lube has pluses and minuses based on the type of use, climate, and degree of maintenance you are willing to put up with. We may consider a review of different chain lubes in the future but for this article we’ll focus on maintenance.
How to lube a chain:
So you’ve had a new chain installed by the professionals at TriSports.com 😉 and you’ve put some miles on it. Things don’t seem as smooth and quiet as when it was new. Its time for some lube.
1) The first step is to clean your chain of the old lube(Remember, this is not a “new” chain but one that has been broken in already). Lubes work best when they are not mixed with different formulas. Pick one and stick with it for the life of the chain. You can either remove your chain and clean it in degreaser (Citrus based or something like Clean Streak) or use an on-the-bike cleaning tool like the Finish Line or Park Tool offerings. Be sure the chain has had a chance to dry off before going to step 2. Wipe the chain through a dry rag until the residual degreaser is gone.
2) With the chain on the bike, apply ONE drop of lube on each roller of the chain. I like to do this on the lower section of the chain as it sits on the bike. This way, the lube is already where it needs to go and won’t get flung off the outside of the chain as it spins around the first time.
3) Turn the cranks for a minute or so (or ride the bike). Is the chain quiet now? Can you hear yourself think again? Now run your finger along the top edge of the chain. You should see a slight wetting from the fresh lube working its way through the chain parts. If its still totally dry, repeat step 2.
4) Take a rag and wipe off the excess lube from the length of the chain. This is VERY important! Repeat this until a clean rag comes away mostly clean.
5) Go ride!
So how about you? How do you clean or lube your chain? Any chain lubes that you think we should try? What problems do you have with chain maintenance?