Is Shimano's TL-CN42 the only reliable tool for chain wear?
12-15-14, 09:53 AM
#1
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Is Shimano's TL-CN42 the only reliable tool for chain wear?
https://pardo.net/bike/pic/fail-004/0...easuring-tools
Above article claims that Shimano's TL-CN42 is the only tool that correctly measures chain wear.
What do you think?
Above article claims that Shimano's TL-CN42 is the only tool that correctly measures chain wear.
What do you think?
12-15-14, 09:55 AM
#2
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There are two reliable tools for measuring wear:
a) Steel ruler
b) The Shimano tool
I use the latter.
ETA: I use the TL-CN41. I wasn't aware they had changed the design.
It looks like it works on the same principle, but sells for half the price.
a) Steel ruler
b) The Shimano tool
I use the latter.
ETA: I use the TL-CN41. I wasn't aware they had changed the design.
It looks like it works on the same principle, but sells for half the price.
Last edited by Shimagnolo; 12-15-14 at 10:01 AM.
12-15-14, 11:10 AM
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The Park tool is ok but the real definitive chain wear guide is a decent steel or aluminum ruler. Measure over 24 pins. On a new chain it should be almost exactly 12.00". If it measures 12-1/1/16" your chain is ok. If it measures 12-1/8", it's replacement time and possibly cassette replacement time also.
12-15-14, 11:16 AM
#5
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Here's my chain-checker. Since I had to use a hand to operate the camera, I couldn't capture using one hand to hold the chain taut:
12-15-14, 11:25 AM
#6
Senior Member
I have had the Rohloff for years and use it as a guide. When it shows a chain is worn out I then use a ruler. I replace at 1/16" in 12".
12-15-14, 11:39 AM
#7
Senior Member
Chain checkers are best used by people who want a simple go/no-go device for checking chain wear. Most won't give you the optimum answer, but they're good enough. I've got a cheap one with measurements for 0.5% and 0.75%. If it fails at 0.5%, I order a new chain, when it fails at 0.75% I plan to replace the next time I'm doing maintenance (Yes, I check the new chain to validate that it passes the 0.5%). I'm sure I could use the chain longer, but I tend to get relatively long life from the chain, and they aren't that expensive (9/10-speed bikes).
If you want to maximize chain life, the accurate measurements are key. If you're more of a mind-set of preventative early replacement a simple $5 chain checker is plenty good.
If you want to maximize chain life, the accurate measurements are key. If you're more of a mind-set of preventative early replacement a simple $5 chain checker is plenty good.
12-15-14, 11:44 AM
#8
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My chain checker is the calendar. New chain every two years whether I need it or not.
12-15-14, 11:45 AM
#10
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Like Data? KMC has a digital LCD display chain wear checker KMC Digital Chain Checker
12-15-14, 11:53 AM
#11
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Chain stretch (wear) isn't something to be anal about. From a pure accuracy standpoint, a 12" steel rule is probably the most accurate because most of the checkers exaggerate stretch by mixing roller play with stretch. This is an issue because the sample is so small.
But, keep in mind that stretch (pin wear) isn't the only wear. There's also roller wear (increase in roller play) that is equally important though we don't measure it. There's no rigid rule for the relative wear rates at the pin and the roller, so even with the most accurate tool in existence you only have a ROUGH INDICATION of the condition of the chain. That's OK, because the 1/16" per 12" rule itself is only a ROUGH GUIDELINE.
In the final analysis, you're making a rough measurement of the chain wear, then comparing it to a rough rule of thumb. So any attempt at precision is an act of self deception. Buy a tool or use a ruler to kind of know where things stand, but don't go crazy over it because all that matters is getting into the right ball park.
But, keep in mind that stretch (pin wear) isn't the only wear. There's also roller wear (increase in roller play) that is equally important though we don't measure it. There's no rigid rule for the relative wear rates at the pin and the roller, so even with the most accurate tool in existence you only have a ROUGH INDICATION of the condition of the chain. That's OK, because the 1/16" per 12" rule itself is only a ROUGH GUIDELINE.
In the final analysis, you're making a rough measurement of the chain wear, then comparing it to a rough rule of thumb. So any attempt at precision is an act of self deception. Buy a tool or use a ruler to kind of know where things stand, but don't go crazy over it because all that matters is getting into the right ball park.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
One accurate measurement is worth a thousand expert opinions - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
One accurate measurement is worth a thousand expert opinions - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
12-15-14, 12:47 PM
#12
Banned
Found Old Full bushing Chains On my single /IGH Drive trains , to last much longer than a 5~8 speed Derailleur chains .
largely a Surface area increase sharing the load .. now Most-all derailleur chains Punch the inner-link in such a way to create a flange ,
out of the steel as the Hole is Made .
The edges of the roller ride on that , so not much surface area ... But the Click shifters work faster, because the chain is Laterally Flexible .
+ no little bushing tubes to make, so that now dominates the market ..
largely a Surface area increase sharing the load .. now Most-all derailleur chains Punch the inner-link in such a way to create a flange ,
out of the steel as the Hole is Made .
The edges of the roller ride on that , so not much surface area ... But the Click shifters work faster, because the chain is Laterally Flexible .
+ no little bushing tubes to make, so that now dominates the market ..
12-15-14, 06:05 PM
#14
Mechanic/Tourist
I agree with FB - buying ANY type of chain gauge when you only have a few personal bikes is nothing but a feel-good exercise for someone who wants to have every tool, whether needed or not. The Park tool and other similar ones are nothing more than a great way for shops to sell more chains.
12-15-14, 06:06 PM
#15
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When I use my steel ruler I also go from 1" - 13". Makes it a little easier to center things.
12-15-14, 06:32 PM
#16
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If you take out your chain for cleaning and lubing, you can hang it alongside a new one and compare length. 1% over 100 links is 1/2", so it's easy to see.
12-15-14, 06:46 PM
#17
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the pedros one works like the shimano. we use the rohloff with good results in the shop. we have used the rohloff for many years. at least 10
12-15-14, 07:57 PM
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I am retired, spend winters in Southern AZ so ride every day, avg 20 miles every day with usually a five or six bike rotation, maintain 9 bikes for me and 5 for daughters and in-laws, and find the accuracy and speed in using a 15" steel rule unbeatable. However, I remember a time when if I took an extra minute to do maintenance on the bike it would cut my ride by that amount, so back then a less accurate but quick check would be well worth the money.
