CHAIN MAINTENANCE

     In the previous post I mentioned cross-chaining.  That got me to thinking more about the chain.  Cross chaining happens when the chain crosses the centerline of the cassette.  That is, if you are in the big chainring and large cog or the small chainring and small cog.  Actually, once you are out of the middle four or five cogs you begin to cross-chain..  This wears on the cassette and the chain, resulting in deformation of the chain and premature wearing out of the cassette.
     Several years ago, I was riding through a neighborhood on my way to the country and saw a young (14-16ish) lady sitting on the sidewalk with her bike in front of her.  I stopped to ask if I could help and she said no, thanks.  So I continued on with my ride.  An hour or two later as I returned, she hadn't moved so I stopped again.  She was having trouble with her chain, which somehow had come off the sprocket and wrapped around itself.  This as a Huffy-type bike.  It took quite a bit of doing but eventually I muscled it back into position.  Apparently it have never been lubricated.  I advised to have her dad use 3 in 1 or WD-40 on it.  I could tell they wouldn't have anything better at home.  All of this to get to what I do in terms of actual maintenance.
       Regular readers know that other than air the tire and lube the chain, and occasionally washing it, I take my bikes to the shop to keep them running.  On average I clean the chain quarterly.  But I lube it bi-weekly, or more if I get caught in wet weather.  I keep a shop towel in the car and after a ride will clean the chain.  I don't wait to get home to do it, the chain gets clean before getting put in the car.  Apparently any oil (i.e. lubricant) on the outside of the chain isn't helpful, plus acts as a sponge to extract the oil that is actually doing its job.  So the sooner you remove the excess the better.
     I use Rock 'N' Roll Gold mostly, but also have Pedro's as backup.  Get the chain saturated, then start wiping off the excess.  It is better if the chain sits overnight.  Don't forget to wipe the pulleys and chainring.
     The other part of chain maintenance is to periodically check the chain length.  Eventually the chain will stretch (it really doesn't "stretch" the bushings get smaller, thus increasing the space between links.  Pay no attention).  A stretched chain will cause a lot of wear on the cogs (read:you can destroy a cassette in a matter of weeks if you have an old, stretched chain), and chainring too for that matter.  It's easy to check.  Twelve chain links should measure exactly twelve inches (from middle of pin to middle of pin)  That's a new chain.  What I've read is you can let it go to 12 1/8 before replacing.  I'd rather just get a new chain.  There is a tool, a chain checker, that will save you from measuring or wondering if it's stretched too far.  You just slap it into the chain, and it tells you if you need to replace or not.  If you aren't getting a clean, crisp shift you might want to check your chain.
     Last year during the Tour de France, Lance Armstrong was commenting on a particular day and what cassettes the pros were using.  He said something to the effect of they were putting the low cogs on, not because they were going to use them, but because the ones they were going to use would be in the middle, thus reducing friction.  I wonder how many watts that relates too.