Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Do Chain Checkers really measure the stated %0.5, %0.75 etc. ?

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Do Chain Checkers really measure the stated %0.5, %0.75 etc. ?

Old 12-04-20, 06:58 PM
  #26  
NJgreyhead
Senior Member
 
NJgreyhead's Avatar
 
Join Date: Sep 2010
Location: South Jersey near PHL
Posts: 779

Bikes: Frequently

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 158 Post(s)
Liked 249 Times in 129 Posts
WRT putting the chain in tension for taking a proper measurement, I put the bike on the workstand with the rear wheel resting on the floor to keep it and the cassette from turning. Then I hang a hammer from one of the pedals in the 3 o'clock position. This puts the upper run of chain in tension. Then I take my measurement (chain checker or tape measure over 12").

I don't think the rear derailleur puts as much tension on the lower run of chain, leading to a less precise measurement.
NJgreyhead is offline  
Likes For NJgreyhead:
Old 12-04-20, 07:15 PM
  #27  
pdlamb
Senior Member
 
Join Date: Dec 2010
Location: northern Deep South
Posts: 8,847

Bikes: Fuji Touring, Novara Randonee

Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 2578 Post(s)
Liked 1,901 Times in 1,193 Posts
Originally Posted by mdarnton
The starting point on most tapes and rules is iffy enough, but when you get to single-purpose tools similar to chain checkers they can be all over the map.
The Park spoke ruler has a very clear starting point, a triangle cut into the ruler at 0. It also goes to 12.5" or so (don't remember exactly and don't care to run to the garage to look at it right now).

Tape measures? I'll usually skip the hook at the end and measure from 1" to 13" (-0/+1/4").
pdlamb is offline  
Old 12-04-20, 07:52 PM
  #28  
2_i 
Senior Member
 
Join Date: Sep 2005
Location: Michigan
Posts: 3,694

Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...

Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 834 Post(s)
Liked 332 Times in 247 Posts
Well, I am late to the party and most of the important points were already made, starting with the fact that the very question of chain wear is not very precise. In any case, in the past I got a chain checker, ProGold Chain Guage, giving continuous wear values and nominally accurate down to about 0.01%. It was the worst checker ever in my hands, off by 0.7%. I returned it and got my money back
2_i is offline  
Old 12-05-20, 02:27 PM
  #29  
NJgreyhead
Senior Member
 
NJgreyhead's Avatar
 
Join Date: Sep 2010
Location: South Jersey near PHL
Posts: 779

Bikes: Frequently

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 158 Post(s)
Liked 249 Times in 129 Posts
Originally Posted by pdlamb
tape measures? I'll usually skip the hook at the end and measure from 1" to 13" (-0/+1/4").
+1
NJgreyhead is offline  
Old 12-05-20, 04:51 PM
  #30  
Bill Kapaun
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,824

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 1774 Post(s)
Liked 1,231 Times in 852 Posts
Originally Posted by pdlamb
The Park spoke ruler has a very clear starting point, a triangle cut into the ruler at 0. It also goes to 12.5" or so (don't remember exactly and don't care to run to the garage to look at it right now).

Tape measures? I'll usually skip the hook at the end and measure from 1" to 13" (-0/+1/4").
12-1/4". I just happen to keep one handy near the computer/kitchen/wheel building table. (I'm obviously single)

Totally agree about NOT using the hook end. They can get bent or simply be wrong. (the sweat shop didn't know it had to be located precisely?)
Bill Kapaun is online now  
Old 12-05-20, 05:38 PM
  #31  
John_E
Senior Member
Thread Starter
 
Join Date: Dec 2020
Posts: 56
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Liked 2 Times in 2 Posts
Ok today I did more measurements on a cold chain. This time I also used a ruler just in case.

It is the same story, I am measuring even less wear with digital caliper which can be explained by the colder weather. However the chain tool still drops in to %0.5. With a ruler on 12" it still measures much less than 1/16". To make sure I remeasured several times and each measurement gave similar results.


Originally Posted by _ForceD_
I ended up getting the Park CC 4 chain checker because I had a discount at Nashbar and ended up getting it for like $7.00. I find it accurate enough for me. I had been measuring with a 12” steel ruler, which is just fine. But, as mentioned in one of the posts above...for real accuracy the chain needs to have some tension. And I suppose the rear derailleur puts enough tension on the chain to measure the bottom of the chain (coming off the chain wheel and going to the rear). But I always felt kinda like I wasn’t holding the ruler precisely in the right spot. The Park CC 4 checker has a little area that, after you hook it into the link, you pinch the chain to the tool to provide the tension required. The end where the reading is taken has two notches on it. If the prong doesn’t fall into the link at all, the chain is 0-49% worn. If it falls to the first notch it’s 50-74% worn. If it falls completely through the link it is worn 75% or greater.

Dan
Park tool cc-4 works the same way Pedro's cc and Shimano's chain checkers.
How are your results compared to the ruler?
John_E is offline  
Old 12-05-20, 06:43 PM
  #32  
_ForceD_
Sr Member on Sr bikes
 
_ForceD_'s Avatar
 
Join Date: Jul 2015
Location: Rhode Island (sometimes in SE Florida)
Posts: 2,306

Bikes: Several...from old junk to new all-carbon.

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1012 Post(s)
Liked 759 Times in 408 Posts
Results are comparable.

Dan
_ForceD_ is offline  
Old 12-06-20, 12:28 AM
  #33  
John_E
Senior Member
Thread Starter
 
Join Date: Dec 2020
Posts: 56
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Liked 2 Times in 2 Posts
Originally Posted by _ForceD_
Results are comparable.

Dan
So, whenever you measure less than 1/16" with a ruler the checker also showed less than %0.5 wear? (The other way around is expected to hold since these tools seem to be over measuring). Asking because it is easy to forget that you never actually cross checked it when the ruler showed less than 1/16" over 12".
John_E is offline  
Old 12-06-20, 06:19 AM
  #34  
NJgreyhead
Senior Member
 
NJgreyhead's Avatar
 
Join Date: Sep 2010
Location: South Jersey near PHL
Posts: 779

Bikes: Frequently

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 158 Post(s)
Liked 249 Times in 129 Posts
Originally Posted by Bill Kapaun
Totally agree about NOT using the hook end. They can get bent or simply be wrong. (the sweat shop didn't know it had to be located precisely?)
The hook end has movement slots so that an accurate inside or outside measurement can be taken (e.g. inside measurement between two walls) allowing for the thickness of the hook.
As they get older and abused (e.g. letting the tape snap back into its housing), tape measure hook-end slots will lengthen, making outside measurements (which use the hook end) inaccurate.

Again, measuring with a tape is most accurate using 1" and 13" to bypass the hook end.
NJgreyhead is offline  
Old 12-06-20, 08:36 AM
  #35  
DaveSSS 
Senior Member
 
Join Date: Sep 2008
Location: Loveland, CO
Posts: 7,213

Bikes: Cinelli superstar disc, two Yoeleo R12

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 1090 Post(s)
Liked 554 Times in 443 Posts
Temperature is not relevant when measuring only a 12 inch length. A 10 degree change would expand the length by 0.0008 inch. Just get a 12 inch machinist's rule and place one end on the edge of a pin. The pin at the other end will be completely covered when the chain is new. When 1/2 of that pin is exposed, you have a little over .5% elongation. As I've already noted, some chains will show little elongation even when severely worn, so the elongation measurement may be worthless. That's why Campy suggests measuring with calipers between outer plates to a length of 132.6mm. It deliberately adds roller wear to elongation. The roller wear is greatest on the hole in the roller.
DaveSSS is offline  
Likes For DaveSSS:
Old 12-06-20, 09:12 AM
  #36  
_ForceD_
Sr Member on Sr bikes
 
_ForceD_'s Avatar
 
Join Date: Jul 2015
Location: Rhode Island (sometimes in SE Florida)
Posts: 2,306

Bikes: Several...from old junk to new all-carbon.

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1012 Post(s)
Liked 759 Times in 408 Posts
I don’t quite understand why so many have doubts or skepticism about the accuracy of chain measuring tools. I get that your preferred way of measuring a chain is using a steel ruler, or a caliper. That’s fine. There’s nothing wrong with that. It’s an acceptable method. Before I got the tool I currently have that’s how I did it. But why is there skepticism about the accuracy of tools specifically designed for the task? I feel like it’s akin to saying something like “I don’t trust Park Tool wrenches because they’re inaccurate. Their tools aren’t the size they say they are.” No...Park (and others) makes quality tools (IMO). They produce a tool that they say is precisely a 15mm wrench and it fits 15mm nuts/bolts, or a crank remover with a specific thread count that screws into your cranks (for examples). Why wouldn’t they be able to produce a chain measuring tool that precisely measures 12 inches?

Dan

Last edited by _ForceD_; 12-06-20 at 09:45 AM.
_ForceD_ is offline  
Old 12-06-20, 10:13 AM
  #37  
Sy Reene
Advocatus Diaboli
 
Sy Reene's Avatar
 
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,613

Bikes: Merlin Cyrene, Nashbar steel CX

Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4717 Post(s)
Liked 1,526 Times in 997 Posts
Originally Posted by _ForceD_
I don’t quite understand why so many have doubts or skepticism about the accuracy of chain measuring tools. I get that your preferred way of measuring a chain is using a steel ruler, or a caliper. That’s fine. There’s nothing wrong with that. It’s an acceptable method. Before I got the tool I currently have that’s how I did it. But why is there skepticism about the accuracy of tools specifically designed for the task? I feel like it’s akin to saying something like “I don’t trust Park Tool wrenches because they’re inaccurate. Their tools aren’t the size they say they are.” No...Park (and others) makes quality tools (IMO). They produce a tool that they say is precisely a 15mm wrench and it fits 15mm nuts/bolts, or a crank remover with a specific thread count that screws into your cranks (for examples). Why wouldn’t they be able to produce a chain measuring tool that precisely measures 12 inches?

Dan
I'm with you. I have a pedro's which I think is fine for checking and provides a simple methodology. But to use your 15mm wrench example, I think what folks are saying, is that a chain checker can be off a bit.. So if you're targeting .5%, if a tool is off by .2%, that would allow your same 15mm wrench to really possibly measure 15.03mm -- and you might actually not be able to say whether or not that might be the case. 3/100 of a mm is very small.
Sy Reene is offline  
Old 12-06-20, 12:59 PM
  #38  
DiabloScott
It's MY mountain
 
DiabloScott's Avatar
 
Join Date: Sep 2006
Location: Mt.Diablo
Posts: 9,991

Bikes: Klein, Merckx, Trek

Mentioned: 70 Post(s)
Tagged: 0 Thread(s)
Quoted: 4311 Post(s)
Liked 2,954 Times in 1,601 Posts
Originally Posted by NJgreyhead

Again, measuring with a tape is most accurate using 1" and 13" to bypass the hook end.
What is the width of the index marks on your tape measure?
DiabloScott is offline  
Old 12-06-20, 01:10 PM
  #39  
Sy Reene
Advocatus Diaboli
 
Sy Reene's Avatar
 
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,613

Bikes: Merlin Cyrene, Nashbar steel CX

Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4717 Post(s)
Liked 1,526 Times in 997 Posts
Originally Posted by DiabloScott
What is the width of the index marks on your tape measure?
If I had a second one of these, I might be able to tell you.

Sy Reene is offline  
Old 12-06-20, 07:16 PM
  #40  
NJgreyhead
Senior Member
 
NJgreyhead's Avatar
 
Join Date: Sep 2010
Location: South Jersey near PHL
Posts: 779

Bikes: Frequently

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 158 Post(s)
Liked 249 Times in 129 Posts
Originally Posted by DiabloScott
What is the width of the index marks on your tape measure?
Seriously?
NJgreyhead is offline  
Old 12-06-20, 08:36 PM
  #41  
John_E
Senior Member
Thread Starter
 
Join Date: Dec 2020
Posts: 56
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Liked 2 Times in 2 Posts
Originally Posted by _ForceD_
I don’t quite understand why so many have doubts or skepticism about the accuracy of chain measuring tools. I get that your preferred way of measuring a chain is using a steel ruler, or a caliper. That’s fine. There’s nothing wrong with that. It’s an acceptable method. Before I got the tool I currently have that’s how I did it. But why is there skepticism about the accuracy of tools specifically designed for the task? I feel like it’s akin to saying something like “I don’t trust Park Tool wrenches because they’re inaccurate. Their tools aren’t the size they say they are.” No...Park (and others) makes quality tools (IMO). They produce a tool that they say is precisely a 15mm wrench and it fits 15mm nuts/bolts, or a crank remover with a specific thread count that screws into your cranks (for examples). Why wouldn’t they be able to produce a chain measuring tool that precisely measures 12 inches?

Dan
I wasn't until I actually measured the stretch with a digital caliper( tool is quite accurate not sure about my way of taking measurement). Understand that we are not making these claims out of nothing.

I am not a machinist but I have experience with cnc machines and know a bit about how accurate/inaccurate they can be. The 15mm tool you are talking about may be 15.05 mm (%0.33 deviation) and it will still work well. I believe some of the standards will let a tool have even a larger deviation which will not hurt functionality.

Here the objective of the tool is to measure a very small difference in chain length,%0.5, so you can not have the deviation percentage that would have been ok with a 15mm wrench.

Since the tool is measuring a distance of 5" it should be accurate enough. It would be ok if it was around %0.45 but it seem to be measuring less here.

If someone who can also verify that these tools are not as accurate as they are advertised it would be great. Especially a machinist's help will be much appreciated.

There are a couple of explanations if they are under measuring:
  1. The companies can not manufacture these checkers with small enough tolerances. They are making them shorter on purpose so that even in the worst case it will not show "no wear" on a chain that has worn to %0.5 (being safe then sorry)
  2. Maybe for some reason they are intended to measure less than %0.5 , say 0.35-0.4 and it would be nice to know why.

I think these tools are useful no matter what. I am also ok with chaining the chain early.

But I am curious as I would like to have a way of measuring the chain wear more precisely than just a couple of threshold points like %0.5,0.75 etc. I would like to see the progression of wear under different riding conditions, lubes etc.
John_E is offline  
Old 12-06-20, 11:14 PM
  #42  
2_i 
Senior Member
 
Join Date: Sep 2005
Location: Michigan
Posts: 3,694

Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...

Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 834 Post(s)
Liked 332 Times in 247 Posts
Originally Posted by John_E
But I am curious as I would like to have a way of measuring the chain wear more precisely than just a couple of threshold points like %0.5,0.75 etc. I would like to see the progression of wear under different riding conditions, lubes etc.
The tools need to be affordable and easy to use. Compact tools are easier to display and ship. For faithful continuous measurements, the tool would need very precise elevating it costs. You can see how much the digital KMC costs.

Chain wear is self-accelerating. With this, when one part of the chain wears more, the difference in wear compared to other parts will grow. Usually the part of the chain after the master link wears most. Are you going to tell the consumers to go around the chain and measure everywhere? You can get a bit different results when you measure distance between pin centers and push the rollers away from each other. When you see an elongation, it will be there in any measure and you may argue in which you pass specific threshold first. For all the factors, 0.25% accuracy for an average consumer in any measure is good enough. If you want to pursue it a scientific level, the field is open.

Overall, lube does not matter. Dust and dirt, riding on small cogs and bad master links are all quite detrimental to the chain.
2_i is offline  
Old 12-06-20, 11:37 PM
  #43  
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Posts: 27,274

Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones

Mentioned: 150 Post(s)
Tagged: 1 Thread(s)
Quoted: 6147 Post(s)
Liked 4,093 Times in 2,325 Posts
Originally Posted by DaveSSS
Temperature is not relevant when measuring only a 12 inch length. A 10 degree change would expand the length by 0.0008 inch. Just get a 12 inch machinist's rule and place one end on the edge of a pin. The pin at the other end will be completely covered when the chain is new. When 1/2 of that pin is exposed, you have a little over .5% elongation. As I've already noted, some chains will show little elongation even when severely worn, so the elongation measurement may be worthless. That's why Campy suggests measuring with calipers between outer plates to a length of 132.6mm. It deliberately adds roller wear to elongation. The roller wear is greatest on the hole in the roller.
This is one of the things that bothers me about people who say to use a 12” rule. Yes, a chain is “exactly” for 24 links...although how much variation is in that measurement. But if you are trying to be so accurate, how do you measure about 12” + 3/32” on a rule that is only 12” long? That is as much of an estimate as the chain checker tools give. “When 1/2 of that pin is exposed” is even less accurate.

Generally speaking, the chain checker tools are good enough. They don’t tend to overestimate chain wear which would lead to drivetrain damage. They actually tend to underestimate the chain wear. If they do underestimate the wear, how much of an impact does that have on the mileage that one can get out of a chain? 100 miles? 200 miles? I really doubt that it would be a significant decrease in chain mileage.
__________________
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!




Last edited by cyccommute; 12-07-20 at 09:11 AM.
cyccommute is offline  
Likes For cyccommute:
Old 12-07-20, 01:39 AM
  #44  
John_E
Senior Member
Thread Starter
 
Join Date: Dec 2020
Posts: 56
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Liked 2 Times in 2 Posts
Originally Posted by 2_i
The tools need to be affordable and easy to use. Compact tools are easier to display and ship. For faithful continuous measurements, the tool would need very precise elevating it costs. You can see how much the digital KMC costs.

... If you want to pursue it a scientific level, the field is open.
...
KMC's digital checker is a vastly overpriced tool, it is nothing more than a $15 digital caliper fitted with flat tips and a spring.

On the other hand I agree that these tools has to be affordable.

As I have mentioned in my post my objective here is mostly scientific. I like to know a confirmation with proof that these tools are overestimating the wear. It would also be good to see if someone can advise a precise way of measuring the wear.
John_E is offline  
Old 12-07-20, 08:43 AM
  #45  
pdlamb
Senior Member
 
Join Date: Dec 2010
Location: northern Deep South
Posts: 8,847

Bikes: Fuji Touring, Novara Randonee

Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 2578 Post(s)
Liked 1,901 Times in 1,193 Posts
Originally Posted by cyccommute
This is one of the things that bothers me about people who say to use a 12” rule. Yes, a chain is “exactly” for 24 links...although how much variation is in that measurement. But if you are trying to be so accurate, how do you measure about 3/32” on a rule that is only 12” long? That is as much of an estimate as the chain checker tools give. “When 1/2 of that pin is exposed” is even less accurate.
I prefer a tape measure, or the Park spoke gauge (with ruler) I mentioned before, for these reasons. Of course, with a little bit of looking you can find a 15" steel rule. If you've got the time to worry about the accuracy of these tools, you've got the time to find one of the 15" rules.

It's going to be a long winter...
pdlamb is offline  
Old 12-07-20, 08:56 AM
  #46  
Racing Dan
Senior Member
 
Racing Dan's Avatar
 
Join Date: Aug 2015
Posts: 2,224
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 1332 Post(s)
Liked 316 Times in 214 Posts
Originally Posted by John_E
This is my first post in the forums. Lately I was interested in doing a little experiment on how lubes/riding style affected chain wear on my bikes. I posted this question on ****** but soon realized that the user base for cycling was not the right one for such questions, not a single answer but some dismissive posts, oh well that is another story. Here is the original post.
I always relied on simple chain checkers like Park Tool cc 3.2 or Pedro's chain checker plus 2.

Lately I began using a digital caliper to measure chain wear to see the progression under different lubes, riding styles etc.

I measure 5 full links from outside, hence roller wear is not included in my measurements. Here are some results :
  1. Brand new Kmc 11speed chain around 5.007-5.011" so <= %0.22

  2. Waxed Kmce 11 speed chain , around ~650miles, almost identical to new, 5.006-5.011" hence <= %0.22

  3. Same Kmc chain on an emtb, around 850 miles, measures 5.012-5.019 hence <= %0.38

  4. Road bike chain, Sram, around 2k miles, measures 5.019-5.022 hence <=%0.44

  5. 10 speed Kmc mtb chain, around 1300 miles, measures 5.032-5.039 hence <=%0.78

Here is what Pedro's show (Park tool seem to agree although it measures the length with added roller wear):
  1. <%0.5, the checker tool show that 0.5 has not been reached.

  2. <%0.5 , same as 1

  3. There is one section where Pedro's show %0.5, it just fits in !!! the rest seems to be a bit smaller than %0.5

  4. =>%0.5 Pedro's 0.5 mark fit in comfortably in every section I measured !

  5. Both Pedro and Parktool fit comfortably and show >>%0.75 wear. !

Now I may be making a measurement error while using the caliper but I have tried many times and several different ways and my measurements seem consistent. I also tried to measure from inside but the knife edges of these calipers make it quite hard to take consistent measurements from the roller to roller since they may not stay parallel to the chain or knife edges may go in between side plates and rollers etc.


Also the problem is not the addition of roller wear as you can see I also use Pedro's chain checker which offsets that.


Although taking the whole chain out and hanging it side by side to a brand new one (same brand/model) would have been much better but I don't have the space for such a setup.




To explain this discrepancy between the checker tools and measurements I tried to measure the distance at the %0.5 wear mark in Pedro's. Measuring this distance is somewhat hard but it seems to be around 5.018 which is interesting since it should be 5.025.


It is still possible that I am making a mistake in my measurements.


So the question is:


-- Has anyone actually checked the accuracy of these tools ? Especially measuring these tools' length as accurately as possible? I want to know If these tools really measure %0.5 wear or something smaller like %0.35-0.4?

I will appreciate if the discussion stays focused on this particular question.

Thanks in advance.
Well obviously they do not gauge true elongation.

Can you Please measure the Pedros and Parp tool with your digital calliper. Should be interesting to know what length Pedros and Park considers "0.5 %".
Racing Dan is offline  
Old 12-07-20, 09:14 AM
  #47  
DaveSSS 
Senior Member
 
Join Date: Sep 2008
Location: Loveland, CO
Posts: 7,213

Bikes: Cinelli superstar disc, two Yoeleo R12

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 1090 Post(s)
Liked 554 Times in 443 Posts
With some chains, like Campy's, measuring only elongation is worthless, since the chain rollers and side clearance wear far faster. Using a 12 inch precision rule is plenty accurate, since 0.5% is a totally arbitrary amount of elongation that someone decided to advertise as the best time to change a chain. While changing at that point will make the cassette perform longer before new-chain skip occurs, there's no proof that 0.4% or 0.6% isn't better. If several chains are used in a rotation, each chain can be used longer, since new-chain skip will never occur and each chain could be used until 1% elongation was reached, IF it's the type of chain that wears primarily by elongation - not all do.

Well known Jobst Brandt postulated that only using a chain with too much elongation would cause new-chain skip, but I proved that wrong by using a Campy 10 chain for 6000 miles on a new cassette. The chain had less than 0.25% elongation at that point, but a new chain skipped on the two most worn sprockets, due to the wear pockets the worn rollers created. A chain with only a few hundred miles of break-in wear did not skip on those same worn sprockets.

https://yarchive.net/bike/sprocket_wear.html
DaveSSS is offline  
Old 12-07-20, 09:15 AM
  #48  
2_i 
Senior Member
 
Join Date: Sep 2005
Location: Michigan
Posts: 3,694

Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...

Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 834 Post(s)
Liked 332 Times in 247 Posts
Originally Posted by John_E
KMC's digital checker is a vastly overpriced tool, it is nothing more than a $15 digital caliper fitted with flat tips and a spring.

On the other hand I agree that these tools has to be affordable.

As I have mentioned in my post my objective here is mostly scientific. I like to know a confirmation with proof that these tools are overestimating the wear. It would also be good to see if someone can advise a precise way of measuring the wear.
I suspect that you never ran an economic forefront of a business. The market for a digital chain checker is none compared to the market for a caliper and the costs are there like for the other product.

In any case, for your task you can buy two identical chains and keep one as a reference and put the other on a bike and then subject them to any measurements that you want. The most relevant is to look at the chain from the point of view of ring teeth and then the distance between the same side of the rollers matters on a stretched chain. The only commercial instruments that test that, which I am aware of, are Shimano TL-CN41 and TL-CN42. However, they tell you again thresholds for chain change. However, yourself you can stretch the chains, put some pins in and measure distance. I.e., you can build up your own scientific/engineering apparatus.

If you measure the wear at 1 day intervals you will see no difference. I may need to wait 2-3 weeks, with bike used every day, to see a 0.05% increase in length. If you treat chains in different ways, such as clean them or not, you will need to wait 2+ months to discern any difference in wear between them. In the meantime the rest of the drivetrain wears off. A drivetrain that is worn wears the chain faster. How are you going to ensure that the drivetrain is in the same shape when trying to quantify in detail chain wear under different conditions unambiguously? Anyway, good luck there.
2_i is offline  
Old 12-07-20, 10:32 AM
  #49  
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Posts: 27,274

Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones

Mentioned: 150 Post(s)
Tagged: 1 Thread(s)
Quoted: 6147 Post(s)
Liked 4,093 Times in 2,325 Posts
Originally Posted by DaveSSS
With some chains, like Campy's, measuring only elongation is worthless, since the chain rollers and side clearance wear far faster. Using a 12 inch precision rule is plenty accurate, since 0.5% is a totally arbitrary amount of elongation that someone decided to advertise as the best time to change a chain. While changing at that point will make the cassette perform longer before new-chain skip occurs, there's no proof that 0.4% or 0.6% isn't better. If several chains are used in a rotation, each chain can be used longer, since new-chain skip will never occur and each chain could be used until 1% elongation was reached, IF it's the type of chain that wears primarily by elongation - not all do.
Again, how can a 12 inch precision rule be accurate at measuring 12” plus any amount? It is precise to exactly 12 inches. Anything over 12” is an estimate and, therefore, inaccurate. Over 12 inches and you might as well use axe handles as a measurement.

As for your assertion that some chains don’t wear by elongation, then why does Campagnolo say to measure the elongation? The suggestion I’ve found says


Here, you need to use a set of calipers to measure the distance between the rollers over 6 outer chain plates. If the length is 132.6 mm it is time to change the chain.
That’s a length measurement. In other words, a measure of elongation. The numbers, by the way don’t seem to work. 12 inches is 304.8mm. 12 inches of chain is 24 links. Divide that by 4 and you get 76.2mm over 6 links. That’s 56.4mm short. Something is not right here.

However, Campagnolo chains aren’t really that widely used. Chain gauges work for 99.9% of chains as a quick measurement. Using one isn’t going to deprive a rider of too many miles on their chain.
__________________
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!



cyccommute is offline  
Old 12-07-20, 11:44 AM
  #50  
Racing Dan
Senior Member
 
Racing Dan's Avatar
 
Join Date: Aug 2015
Posts: 2,224
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 1332 Post(s)
Liked 316 Times in 214 Posts
Originally Posted by cyccommute
Again, how can a 12 inch precision rule be accurate at measuring 12” plus any amount? It is precise to exactly 12 inches. Anything over 12” is an estimate and, therefore, inaccurate. Over 12 inches and you might as well use axe handles as a measurement.

As for your assertion that some chains don’t wear by elongation, then why does Campagnolo say to measure the elongation? The suggestion I’ve found says




That’s a length measurement. In other words, a measure of elongation. The numbers, by the way don’t seem to work. 12 inches is 304.8mm. 12 inches of chain is 24 links. Divide that by 4 and you get 76.2mm over 6 links. That’s 56.4mm short. Something is not right here.

However, Campagnolo chains aren’t really that widely used. Chain gauges work for 99.9% of chains as a quick measurement. Using one isn’t going to deprive a rider of too many miles on their chain.
How do you know? To date I have never seen ANY post on any forum identifying what length Park or any other tool uses to gauge if a chain is worn out or not. Im betting you didnt measure a gauge either?
Racing Dan is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.