Chainwear indicators/measuring tools

[Danneaux]

Santa arrived with a small but very welcome prize for me -- a Shimano TL-CN42 chain-checker:
https://www.sjscycles.co.uk/tools/shimano-tlcn42-chain-wear-indicator-y12160000/?geoc=US
It is a design that tensions the rollers on the same side so real stretch (wear) can be measured:


It is a go-no go design, but seems to work well for determining when the chain has stretched to a point where further use would cause undue drivetrain wear. Of course, I have measured every chain in sight and checked it against my usual method of comparing to a rule to be sure! 

Hoping you all received some nice bike goodies from Santa as well.

All the best,

Dan.

[Andre Jute]

Santa arrived with a small but very welcome prize for me -- a Shimano TL-CN42 chain-checker:
https://www.sjscycles.co.uk/tools/shimano-tlcn42-chain-wear-indicator-y12160000/?geoc=US

Does it work on any chain or only Shimano models, Dan?

[Danneaux]

Works a treat on any chain, Andre. I just used it on my tandem's timing chain and confirmed my other measurements showing it is right at the point of replacement. It works on my Deda, Taya, KMC, Sedis, SunTour (yes, I still have a few...) and Regina (those too!) chains, so not Shimano-specific.

It is perhaps the nicest of the same-sided checkers to use, simply because it is so easy. You don't need two hands, simply engage the spring end and just sort of drop the tooth on the chain. The instructions included with my TL-CN42 say, "If the tool is pressed forcibly in Step2, the diagnosis will be inaccurate. Lightly apply the tool on the chain". Gently carries the day here and the weight of the tool itself seems to be plenty to engage the tool's tooth if the chain is sufficiently worn.

It looks like it would be as nice to pack on a long tour as it is to use in the shop at home. A really ingenious design, brilliant in its simplicity. I especially like the loss-proof laser-etched pictographic instructions on the tool itself. It works on the top or bottom run of chain and so far, gets full marks from me

If you shop carefully (as I er, "Santa" did), you can find them for about half price, well worth it for the convenience and speed.

Addendum: The Shimano TL-CN41 ( https://www.amazon.com/Shimano-TL-CN41-Chain-Wear-Indicator/dp/B00346ZEOE ) gives the same results, but I found it more awkward to use, requiring two hands to get it placed correctly; same with the Pedro's chain checker ( http://pedros.com/products/tools/general-tool/chain-checker-plus/ ).

For a nice treatise on the need for same-sided chain checkers and why they are more accurate, see: http://pardo.net/bike/pic/fail-004/000.html

All the best,

Dan.

[Andre Jute]

Works a treat on any chain, Andre.

I looked into it, read the fascinating link you provided, and decided against it. For the gauge, if I ran my chains to the limit, I could recover the cost in five chains. Against the gauge, I use an inexpensive chain (KMC X8) every few years. I'd be dead before I recovered the cost.

But that isn't the main reason. On the principle that the chain is the cheapest wearing part in my transmission, and I don't want a worn chain wearing my sprocket or chainring, with the associated bother of replacing either, I replace the chain at 0.5mm wear. This is part of the system I've built for a near-zero maintenance bike. Thus it is irrelevant to me, as a low mileage, near-zero maintenance cyclist, whether a better gauge would permit greater precision in observing the wear of chains. I throw off the chain before precision in wear ever becomes relevant.

If I were a high mileage cyclist who fitted new chains often, of course I might take a different view.

Thanks all the same for providing input to come to a reasoned decision, Dan. I'm sure that in your hands, a high-miler, the gauge will soon recover its capital outlay.

[Danneaux]

Thanks all the same for providing input to come to a reasoned decision, Dan. I'm sure that in your hands, a high-miler, the gauge will soon recover its capital outlay.

Very welcome, Andre. Yes, I can pretty easily do 9,000km in four months of summer riding, so I need to keep an eye on my chains' wear while stretching them as far as reasonable without imperiling chainrings and cogs. At USD$20 on sale, the checker is a pretty good deal for me.

That said, I see why "early" replacement works well for you Andre, and how it eliminates much hassle and reduces wear to levels even below what this gauge can indicate.

All the best,

Dan.

[Matt2matt2002]

Thanks for this tip Dan.
Santa left me some money so I'll splash the cash on one.

BTW my notes tell me I have done 6,718 miles on my chain - KMC X1.
Always within a Chainglider. Put on to new front and rear cogs.
Always run on the slack side.

I'll let you know the results when I have measured the chain.

Matt

[alfie1952]

I have the Caliber 2 chain wear indicator which is the same type of tool. I have just checked my SportsTour which has I believe 4100 km on a SLT99 chain with almost no wear. I recently fitted a KMC X1 on my Nomad but doubt if this will wear as well as the Rohloff chain.

Alfie

[Danneaux]

I have the Caliber 2 chain wear indicator which is the same type of tool.

<nods> Yes, the same type, but the Rohloff works by pushing the rollers apart, which will result in earlier replacement of the chain than indicated by tools that push on the same sides of the rollers.

This is no bad thing for drivetrain lifespan, as it offers a wider margin of safety. The downside is earlier chain replacement than may be absolutely necessary. Again, as shown by Andre's experience, this will guarantee extended life for chainrings and cogs and as he mentioned, chains are cheap compared to other components. Chain cost assumes greater importance if one consistently puts in high miles. An additional argument can be made for early replacement, as indicated by the Rohloff tool: On derailleur applications a worn chain also becomes more flexible laterally, and this can cause shifting performance to degrade. A nice thing about the Caliber 2 is it has two scales -- one for drivetrains with aluminum alloy cogs and the other for steel. When used on a steel-cog drivetrain, the aluminum indicator will give a nice heads-up of early wear (0.075mm vs 0.1mm) so you can have a new chain at the ready when the steel side indicates replacement in a little while longer.

Chain wear indications made by opposite-side and same-side tools will vary. One isolates roller wear, the other does not. The Rohloff diagram here... https://www.rohloff.de/fileadmin/_migrated/content_uploads/Beschreibung_Caliber2_de_en_it_fr_nl_es.PDF ...shows how the Caliber 2 pushes the rollers apart, rather than measuring from the same side. Either is a valid measure of chain wear, but will not give the same results.

All the best,

Dan.

[jags]

Oh Lord i just checked the price on that thing Ł29.99 are they having a laugh .
would a fella not be better off making one himself from a piece stainless steel when you buy a new chain  obviously.

anto.

[Danneaux]

...would a fella not be better off making one himself...

The checking tools are mostly a convenience, Anto. Up till now, I've just hung the chain from a nail and used a measuring stick/rule/meter or yardstick to check chain wear. It has worked well and cost nothing. 

All the best,

Dan.

[Andre Jute]

BTW my notes tell me I have done 6,718 miles on my chain - KMC X1.
Always within a Chainglider. Put on to new front and rear cogs.
Always run on the slack side.

What was your previous chain, and what mileage did you get on it, Matt? (Or do I remember correctly, the Thorn is your first bike?)

Even if you're heavy on transmissions, as I am, it seems to me you will have to get at least half that mileage again to justify the price of the X1, unless it has some other advantage than extra longevity. (Nothing to do with the cost of the gauge which is the subject of this thread,  though it would be a nice thing to have if you're a toolfondler; I had to restrain myself mightily from buying the thing anyway, just to have it.)

Chain on the slack side is better than on the tight, according to the Rohloff manual.

[mickeg]

Thanks for posting, I was unaware anyone made a tool that took both measurements from the same side.

I might check a chain about two or three times a year, and then do it when I have the chain off the bike anyway.  So, I think I will stick with the old fashion method of using a really long ruler.

[alfie1952]

As you say Dan it is just a convenience,  your TL CN42 would give a truer measure of chain wear. I  still measure stretch with a steel rule, I do not have the money to replace expensive chains when not needed. Recently I bought a KMC B1 chain, very cheap and was wondering if anyone is using this chain and what are their opinions on it.

Wishing you all the best for the new year.

Regards Alfie

[mickeg]

... Recently I bought a KMC B1 chain, very cheap and was wondering if anyone is using this chain and what are their opinions on it.
...

I always buy the cheapest KMC chains, I have no idea if I ever used a B1.  But quite frankly since I get the cheapest ones, I am quick to replace them instead of push them to the point where they wear out other parts.

[ají]

...would a fella not be better off making one himself...

The checking tools are mostly a convenience, Anto. Up till now, I've just hung the chain from a nail and used a measuring stick/rule/meter or yardstick to check chain wear. It has worked well and cost nothing. 

All the best,

Dan.

so its not necessary to get the rohloff specific chainwear tool?