Posts Tagged ‘clean’

Always Keep Your Drivetrain Clean

March 1st, 2011 No comments

In the first installment of my bike maintenance series I’d like to address the most important piece of maintenance you can perform. It is also the easiest. Like the camshaft in an engine, the chain is responsible for transferring the power generated by your legs directly to the rear wheel. If you think about how much force you can apply to the pedals it’s actually pretty amazing that the chain holds up as well as it does. That being said, here’s the first hard lesson I learned about the chain: it is designed to be replaced often. How often? That depends on how well you keep it maintained.

Chains are susceptible to “stretch.” This is not the stretching of the links as one might think, but the wearing of a little grooves in the pins of the chain by the rotating “rollers.” As each pin gets a tiny groove worn in it, the sum of all the grooves over the length of the chain can be quite large. You can easily measure this with a ruler, by placing the 1st ruler mark on one of the pins and seeing where the 12″ mark of the ruler lies. If the 12″ mark is right on a pin, then your chain has not stretched. If the pin is 1/16″ over the 12″ mark, you need a new chain. If it’s over that you may even need a new cassette. I usually go around 1000 miles before replacing my chain, but I measure it regularly to be sure. It’s a lesson I learned the hard way when I was young, and I will not soon forget it.

So how do you keep a chain well maintained so that it will last as long as possible? The answer is frequent cleaning and lubrication. What I am going to say here is probably a heresy in some circles, but I learned it from a longtime bike commuter and I trust his judgement. Cleaning/oiling your chain should be the easiest thing you do, because if it’s not you won’t do it as often as you should. I do it once a week when I am riding regularly, and always do it immediately after riding in the rain or on wet roads.

Dirty Chain

Eww, Nasty!

Unfortunately, cleaning a chain the way that most people will tell you to is a pain. This usually involves a special chain cleaning tool (an expensive uni-tasker), or removing the chain to soak it in de-greaser (messy and wasteful). If you aren’t lucky enough to have a chain with a “master-link” removing a chain with a chain tool can even do more harm than good! The secret to an easy chain cleaning is to use the oil itself to clean. Remember what we are shooting for is to lubricate the junction between the pins and the rollers located inside the link, that’s where the main source of chain wear is located. The only way to get in there is with a good penetrating oil, and to work the rollers around the pins lubricating the inner surface. The oil should be thin enough to be drawn into the roller by capillary action. Don’t even think about reaching for the WD-40, that stuff will mess your ride up! Get a good chain lube from a bike store. I was recommended ProLink by my commuter friend and it has not let me down.

Apply the oil to the inside edge of the chain

Apply Oil Here

Once you have your oil of choice you want to soak a good amount of it into your chain. Apply the oil to the inside edge of the chain and run the pedals backwards to work it in. This initial application of excess oil should flush out the small grit that is inside the rollers and draw it to the outside. I usually follow this up with running a rag lightly under the bottom of the chain to get the excess off, and then I will pedal forward running the bike through all of its gears to clean the teeth. Now wipe the chain down well with a rag to get all the dirty oil off, you can run the pedals backwards for this too and hold the chain in the rag to give it a good cleaning. At this point the teeth of your chainrings and cassette are probably covered with dirty oil as well, so I go over them with the rag too, working the edge of the rag in between the rings. Wipe down the derailer cogs as well as these can get pretty dirty, I usually hold the non-chain side tightly with the rag and run the pedals backwards to clean them off.

Work the rag in between the rings to clean the cassette

Wipe off the cassette and chainrings

If this is your weekly maintenance, things should be pretty clean at this point, but you may need to repeat the soak-drive-wipe cycle again if things are really dirty. Once the oil starts coming clean you should be in pretty good shape to actually lubricate the chain. I do this by applying a drop of oil to each roller. It helps if you have a point of reference to start from like a master-link. Could you just squirt a bunch on the chain and run it around a bit? Probably, but remember once the oil goes on it starts flowing out of the chain, not into it, so you may miss some links. By oiling every roller you assure that the lubricant is where it should be right from the start. Once you’ve finished the whole length of the chain, dab the excess off the bottom of the chain with a clean rag. I also put a drop of oil on the inside of each of the derailer cogs. They are not under extreme tension, but they do make a lot of noise when dirty.

All done!

All done!

With that you should be done, and the whole process doesn’t take longer than about 15 minutes. That should be easy enough to get you doing it all the time, which is the goal. Remember, chains are cheap, but a stretched chain can ruin a $100-$200 cassette in no time at all. Don’t neglect this important task!

Feel free to respond with any suggestions or questions you might have!