Aside from your tires, the most critical and commonly replaced part on your bike is the chain. A worn chain reduces shifting quality and can dramatically shorten the life of your drive train. A worn chain lengthens as the internal bushings in each link wear. The now longer chain puts more pressure on each tooth on your cassette cogs and each tooth on your chainrings, so the teeth wear more quickly. The problem is simple, but so is the solution. If you periodically replace your chain, your expensive drive train parts will last longer and, with a little care, a lot longer. You’ll save money and the gears will shift better – a new Shimano Dura-Ace 10 speed chain retails for $69.99, but a Dura-Ace cassette retails for $264.99 and a new 53 tooth chainring costs nearly as much! Clearly, timely replacement of your chain will save you in the long run.
But, when should you change your chain? If we are keeping it simple, then replace your road chain every 1,500 to 2,000 miles or your mountain chain every 5-6 months. But these are only general guidelines – you are probably not the average rider. For instance, if you meticulously maintain your chain – keep it clean and lightly lubricated – and never ride when the streets are wet, weigh 135 pounds, and always sit and smoothly spin a low gear, your chain will last a lot longer than your 250 pound buddy who grinds a massive gear, rides everyday in a typhoon and doesn’t even know how to spell maintenance.
Clearly the rules do not work for every rider. The good news is that you can easily measure chain wear, and only replace your chain when it is necessary- when it’s worn. The easiest way is to use a chain wear gauge like the Spin Doctor Chain Wear Indicator. To use this tool, put pressure on a pedal so that the top of the chain is drawn taut, then drop the tool in place and read the results.
Don’t have a chain wear indicator handy? There is another way and all it takes is a 12 inch ruler. All modern chains have rivets every ½” and you are going to measure from one rivet to another one 12” away. Once again draw the top of the chain taut then align the end of the ruler (the zero inch mark) with the center of a rivet. Now note where the ruler’s 12 inch mark aligns.
- If it is dead center on a rivet, the chain is as good as new.
- If the rivet is less than a 1/16″ ahead of the 12” mark, then the chain is showing some wear but is still serviceable (this is equal to 1.58mm or .5% wear).
- If the rivet is 3/32” ahead, start thinking about a replacement. Replacing it now prolongs the usable life of the cassette and chain rings (this is equal to 2.38mm or approximately: .75% or 2.29mm of wear).
- If the rivet is 1/8″ ahead, replace the chain immediately and you may need to replace the cassette (this is equal to 3.175mm or approximately: 1% or 3.05mm of wear).
If you measure your chain and determine that’s it is time to replace your chain, it’s actually a relatively easy task to take care of on your own. The only tool that you need is a chain tool, like our Spin Doctor Universal Chain Tool, and your brand new chain. But instead of writing out the steps to replace a bicycle chain, we’re going to show you in one of our handy Spin Doctor How-To Videos:
If you need more help with your bicycle repair needs, head to your local Performance Bicycle store and set up a visit with your local Spin Doctor. Don’t live near one of our stores and need some technical advice? Get in touch with our Spin Doctor Tech Support team by email or phone – they are always ready to help with your technical questions.