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I have gotten a hold of a BBB chain wear tool to check my KMC x10sp chain. It seems to indicate I am at least at 75% wear. The chain checker does not have a serial or model number I can use to get more detailed info about it.

Are all chain wear tools universal or are they only to be used on a specific speeds of chain?

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No, not all chain wear tools are universal.

There are two types of chain wear tools:

  • Chain wear tools that measure from different sides of rollers
  • Chain wear tools that measure from same side of rollers

If a chain wear tool measures from different sides of rollers, roller clearance and roller diameter enter into the equation. A tool only works then given some assumptions of roller clearance and roller diameter. A complicating factor is that roller clearance increases as chain wears, but it's not the reason why worn chains are discarded. This kind of chain wear tool may give inaccurate measurement for a new chain if the tool is not compatible with the chain brand. Unfortunately, there's no way to say which tool works for which chain brand.

Chain wear tool that measures from same side of rollers measures only chain pitch, which is the parameter you want to measure. An out-of-pitch chain is the reason why we throw away worn chains.

Tools that measure from same side of roller:

  • Shimano TL-CN40, TL-CN41, TL-CN42
  • Park Tool CC-4 (don't buy any other tool from the CC series, only CC-4 is accurate)
  • Pedro's Chain Checker Plus II
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  • The only chain I know of that use a different roller size is the SRAM flat-top chain. Apart from that, my understanding is that roller diameter is part of the 1"-pitch chain standard.
    – Adam Rice
    Commented Oct 10, 2022 at 21:20
  • I can confirm that some cheaper chain gauges indicate that even relatively or even completely new KMC chains from Dectahlon are worn while the Parktool CC-4 tool indicates that it is still OK.
    – Vladimir F Героям слава
    Commented Oct 10, 2022 at 22:27
  • The outer surface of the roller should not rotate relative to the the chainring surface, assuming proper lubrication inside the chain, so there should be no wear to the outside of the roller. The wear surfaces are between the inside of the roller and the pin, optionally separated by a bushing. A chain that is out of spec for one type of tool will be out of spec with the other type of tool.
    – Emyr
    Commented Oct 25, 2022 at 12:25
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I tried many of them, none seemed to be precise enough.

The best method is to remove your chain, get a new one for same "speeds", lay them side by side. If you chain is worn, it will elongate - the old chain will be longer then the new one with the exact same roller count.

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    It can be hard to detect the stretch visually, though. You also have to remember that your existing chain is probably shortened. Are you going to count links and trim the new chain? How do you keep the chains in tension so that you are actually detecting the length correctly? You might as well use a ruler, and that process is already ,regarded as too imprecise
    – Weiwen Ng
    Commented Dec 6, 2022 at 22:03
  • " the old chain will be longer then the new one with the exact same roller count." - yes, I already know the chain is probably shortened. You don't need to "tension" the chain. Just pull from one end, when lying them both, side by side. It's not imprecise: you gonna be looking for .5mm to 0.75mm elongation in 8-10 links with a chain gauge - that's half to 3/4 centimeter with a shortened chains (never saw a chain shorter then 100 links)
    – Barış Atasoy
    Commented Dec 6, 2022 at 22:11
  • I was under the impression that chain stretch isn't actually stretching the change so it's longer, but more wear in the rollers and pins. Am I wrong?
    – Hursey
    Commented Dec 8, 2022 at 1:21
  • Yes - chains do not stretch. As you pointed out, roller and pin wear cause them to elongate.
    – Barış Atasoy
    Commented Dec 8, 2022 at 9:31

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