Mr. Road BIke above is fanatical about chain changing!  Of course they love you at your Trek store.  I don't really get the logic though.  Changing your chain as frequently as every 1,200 miles and keeping it super clean and lubed greatly minimizes the need to change your gears as frequently as you do.  I'm still on my originalDura-acechain rings on my four year old Felt F1C (somewhere around 18,000 miles on the bike, maybe more), and while I do altenate my cassettes the one with the most miles on it, probably about 12,000 is not skipping yet. 

As posted earlier, using a chain checker is probably the best method of assessing chain wear though unless all you do is ride up steep hills my bet is that your chain can last longer and certainly your gears will.  You change it frequently enough that I'm sure that your wear and tear is minimal.  Can I have your "worn out" ones?

EJ

For a couple of seasons this was my story, too--replacing chains twice a season. But when I sniffed around a little, I found that a 1400 mile replacement cycle was very much untypically short. I didn't spend a 'thousands' on my bike, but I don't skimp, either. I do think it's a huge waste spending money on chains which could be spent on gear to improve riding. Between regular cleaning and good pedaling technique (primarily staying off the small sprockets and using a lower gear to keep from stand on the pedals) I'm getting 2 or 3 times the life out of a chain that I used to. And it's even more fun.

CPW

I'm going to risk beating this topic to death with a hint I got from Bicycling Magazine's _Complete Guide to Bicycle Maintenance…_ . On a new chain 12 full links are exactly 12 inches long with a little tension on the chain. You can get a pretty good indication of chain wear by laying a 12 inch ruler along the top of your chain and noting how long 12 links measure out. Replace the chain when 12 links measure 12 1/8 inches or more. This works out to about a 1% stretch or about 0.005" per pin--not much and not something you're likely to pick up by feel. The gauge that shops use is probably more precise, but it only does one link. The Complete Guide's method may give you a better indication of the condition of the entire chain. It also has the advantage of being something you can do at home when you're doing routine maintenance. If you're suspicious that you might be wrong, you can always ride up to the shop and have them take a look.

CPW

I probably mistook what I saw when I was looking over the tech's shoulder.

MS,

You have missed the point entirely.  The previous emails have made this point repeatedly.

Don't change your chain and you will wear out the cogs and chain rings so that  when you do get the skip you are in for the big bucks to replace those items as well. I suggested checking the chain about 1,500 miles in but my bet is that most will get 2,500 miles to 3,000 before it gets to about .75 on the scale which to me means time to change the chain and still keep your cassette and chain rings as they did not wear out unevenly because you thought you were saving money.

My previous note even suggested that some shop personell wait too long to suggest to you to change the chain.  Wait til it gets to 1.0 on the scale and you may have to replace the more expensive items.

If it were your car, why change the oil? It is probably running just fine.  Just wait until your engine seizes up while on a cross country driving trip and you have to call for a ride home.  Change your chain as you would your oil. Or in my case I should change my oil as I would my chain. 

Now, since you have gone 7K, I'd measure it but if it is stretched beyond 1.0 I'd now ride it to oblivion but expect to by a new cassette and prossibly chain rings too. That will cost you.

EJ

To minimize the risk of wearing out the cassettes prematurely it is advised to change your chain more frequently. What does that mean? I would say when it is at .75 on the checker tool.  Waiting until 1.0 as others may advise may be a little too long in my mind.  Many don't have the luck you did with changing a chain at 10K and not having a new chain skip on the cassette. Good for you that you didn't.  I am not advising to change it as frequently as 1,200 miles but most will feel the improvement whenever a change takes place. Experience is the evidence you've requested garnered from many riders and mechanics whom I polled.

To me, the point of changing the chain is to avoid having to incur the cost of changing the cassettes or chain rings frequently. Most mechanics recommend, first, keeping the drive chain clean and lubricated. Secondly, change the chain when the checker is at .75.  It seems prudent to do so.  Your point about the engine at 50K is my point exactly. Change your oil frequently, etc. and you will most likely have an engine that will last longer. No need to replace it.   Likewise, change your chain frequently and keep it clean and your gears will last longer too.

EJ

What kind of riding do you do, what kind of bike and most important what kind of mileage do you get from what kind of chain. I used White Lightning for a couple of years. I understand from the ad, WL comprises paraffin in a solvent which evaporates leaving the rubbing surfacces with a paraffin coating. I didn't get the longevity I'd hoped for, and I began to suspect the the lubricant wasn't getting to the wearing surfaces betweem the pins and the side plates. Or maybe the solution simply ran off the surface. This would depend a lot on how the solvent 'wets' the chain surfaces. I started using Finish Line dry teflon lube and have been getting better results, but I can't tell whether it's the lube, more conscientious cleaning or better pedalling technique. It's very bad science to change two variables simultaneously in a test, but no one's perfect.

CPW

PS--I think this topic would make a really good FAQ on how to maintain chains.

Thank you. If it hops on the highest (smallest sprocket) gear on the cassette, it's worn out. Otherwise don't waist your money.

Also, the lubricating properties of the best synthetic oils greatly exceed any bicycle chain lube or they wouldn't use it in the most abused engines in the world!

This thread is amazing!]:)