is the chain, chain rings, cassettes, and derailleurs. Chains and Chain Rings - A worn out and stretched chain can cause some serious shifting issues and wears out the other parts of your bike very quickly. There is a tool to measure chain stretch, but you can tell if you need a new one two ways. First, look at the bottom of the chain ring with the chain in the biggest gear. If there’s a gap, or you can see an entire tooth on the ring, the chain is pretty much shot. If you ride a lot, and ride hard, it’s pretty common to go through a chain every other month or so. Cassettes - When the chain goes, the cassettes are sure to follow. Chains and cassettes wear at the same rate, and they actually wear to each other. Putting a new chain on an old cassette won’t do much to improve shifting because the cassette is worn a particular way and won’t line up very well with a fresh, tight chain. Some mechanics preach that replacing the chain when it is at about 75% wear makes it possible to keep the same cassette for much longer. A somewhat common practice is to use switch the cassette every two chains, or roughly 3,000 miles. If you ride hard and push a big gear, it might be better to change both at once.
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A chain ring, however, lasts much longer than both. When the teeth of the chain rings get shorter and sharper, it may be time to replace it. Ask your mechanic when the right time comes. Derailleur - The derailleur is a complex, fickle and testy component that has a huge impact on the quality of your shifting. Luckily, making sure they are working is as easy as turning the crack and trying to move the chain around the cassette. Make sure the derailleurs are tight by grabbing them and moving them side-to-side. If there is some lateral play, carefully tighten them if you feel comfortable. If the derailleur is way off, look to see if there is worn paint above or below the derailleur. If you see some chipped off, the entire derailleur may have moved, throwing it off-line of the cassette or chain ring. Try to line it back up and make sure everything is lined up straight before tightening the derailleur back down. These are some quick and easy ways to make sure your bike is up for a new season of fun and adventure. These simple checks make your ride safer and the bike last longer, so try to look them over every once in a while. Keep it safe, keep it clean, and keep it rubber side down in 2012!
Northern Motion