Chain replacement time? Shimano 10 speed (CN 5701)
 

I searched a bit but I don't think I learned shimano's recommendation for chain wear and replacement.

I just purchased a "spin doctor" chain wear indicator and checked my chain, which has 4700 miles on it. This wear indicator is able to fit the 0.75 notch but not the 1.0 notch. Does this mean I need to get a new chain or can I wait until the stretch is enough to fit the 1.0 notch?

The safest bet is to use a ruler and if when measured pin to pin the last pin actually comes out to around the 12 1/16th mark that is usually a good sign to replace your chain.

My experience is that more cog wear happens in the last bit of chain wear. So a chain replaced at 2/3 or 3/4 of it's measured wear migh only have worn the cassette cogs to 1/3 or 1/2 their amount. So you do the math to the cost of each, and when they're repalced, and the performance of lost chain shifting due to increased flex (not measured by any gauge I know of) with a very work chain. Andy.

There are two schools of thought for chain replacement.

1. Replace the chain often, say at 1/2% elongation or less to protect the cassett, particularly the most used few cogs. That way the cassette lasts longer but you may be changing chains at 2000 mile or even less intervals.

2. Run the chain until it's at least 1% elongated and/or shifting poorly and replace it and the cassette together. This can take anything from 5,000 to 10,000 miles for many riders.

So do you pay for several chains to protect one cassette? To some extent it depends on the cost of the cassette. I use 105 and Veloce cassettes at about $50 each so buying $150 or more worth of chains to extend their life 2 or 3x isn't cost effective. If i used Dura Ace or Record cassettes, the cost picture would be a lot different.

BTW, unless you run the chain WAY beyond 1% elongation, you won't damage your chainrings so that's not a factor. I run my chains and cassettes about 8,000 miles between changes and have chainrings with well over 25,000 miles that still look, shift and run fine.

Remove the chain to clean it and replace at 1/16" wear. The cogset should last quite a while. I clean my chain in an ultrasonic cleaner and they (8speed) have lasted 16,000 miles. The cogs go at least 30k miles.

Thank you all for taking the time to give me some insight into chain wear.

It looks like it's falling between 12 1/16 and 12 2/16.


Thanks Andrew and HillRider. I see there is a bit of strategy involved in determining when to replace.

I have gotten into the routine of doing a "full" cleaning about once every two weeks, can be a few days sooner depending on conditions encountered. I always remove the chain and give it a good degreasing and re-lube. In between those washings (usually ay least twice) I just use degreaser on a rag and wipe the chain, cogs and chainrings then let them dry and apply more lube to the chain.