After how many miles should you replace your chain and rear cassette? I’ve gotten conflicting recommendations. Thanks!
measure it.
A chain wear indicator is a pretty good investment. Performance is currently selling them for $4.99, and they’re even offering a 15% discount at the moment. If you keep on top of chain replacement and overall drivetrain cleanliness, your cassette should last a pretty long time.
After how many miles should you replace your chain and rear cassette? I’ve gotten conflicting recommendations. Thanks!
Hard to give an set answer, due to variables like how well/often you clean/maintain it, and the type of loading you put on it (spinner vs masher, whether you run cross-chain gear combos a lot, shift under heavy loads, etc). As suggested, measuring tool is a better bet than just throwing out a number.
measure it. OK fine, I have done this in the past and replaced my chain as needed.
But i have also measured it and the chain was so bad that it is past the worst case scenerio on the measuring tool. At the same time my bike seems to be working just fine. What is the downside to riding with an old chain and old cassette? Is it more likely to break? Am i losing out on efficiency?
You will wear down the teeth on your rings, deraileur and cassette due to the longer space that is a result of the stretched chain. Instead of swapping out chains you will be replacing a cassette and front chain rings. Not worth it, just swap chains out regularly.
Dave
the teeth on the cassette and rings are spaced to mesh with an outstretched chain. When the chain stretches out, it no longer meshes well with the cogs and it starts to wear down the teeth to match the new spacing. Since the cogs wear to match the chain, you could ride a chain until it snaps, and you probably wouldn’t notice a huge drop in performance, but when you install a new chain, with the correcting link spacing, it’s going to ride like crap because the tolerances on the cogs have opened up so much. Once you hit this point, you have to replace the cassette and rings.
So you can choose to replace a $30 chain a little more often, or spend a few hundred dollars on a new cassette and rings every time to wear out a chain.
Some of us keep several chains in rotation. While one or more is off the bike getting cleaned and lubed, the other is on performing its duty. I keep 3 in rotation, each gets pulled off after about 2 weeks’ riding, or after one wet ride. I only have to replace a chain or two after one gets physically damaged pretty much, they never seem to really wear out this way. I occasionally see a good deal on a wipperman and pull a chain out of service for a new one.
In all the years I have been riding - about 15 now, I have never had to replace a cassette due to wear, and as far as I can recall, they have all been D/A cassettes. Chain rings do see wear and when they get “pointy” they get replaced.
measure it. OK fine, I have done this in the past and replaced my chain as needed.
But i have also measured it and the chain was so bad that it is past the worst case scenerio on the measuring tool. At the same time my bike seems to be working just fine. What is the downside to riding with an old chain and old cassette? Is it more likely to break? Am i losing out on efficiency?
I just got a pretty good demonstration of this a few weeks ago. I was visiting my parents, and while I was down there I tuned up all of their bikes. Two of the bikes in the collection are their older hybrids, now mostly replaced by straight-bar road bikes, but still used for sloppy road conditions and beach expeditions. The hybrids’ chains were REALLY worn out, so I replaced them. No major problem on Mom’s bike post chain replacement, other than a little bit of skipping on the smallest cog when really mashing. My dad’s, however, skipped badly on three of the small cogs. (Not too surprising; Mom is a spinner, and Dad is a masher.)
Fortunately the LBS had a 7-speed cassette on hand, so I was able to get everything working properly before I left. Also fortunate that the chainring teeth hadn’t gotten badly enough hooked to start causing chain suck. (Aptly named phenomenon.) The bike has a triple chainring, it’s spent its whole life in a salt-air environment, and I’m not sure that the bottom bracket has ever gotten any maintenance. VERY happy not to have had to pull the crankset to replace the chainrings.