Vernier caliper for chain wear measurements

Discuss light weight issues concerning road bikes & parts.
jesper2913
Posts: 46
Joined: Sun Jul 28, 2019 5:15 pm

by jesper2913

I think I get know, where you're going. But isn't it important as well, what the equivalent "lengt"/diameter of cassettes, chaingrings and pulleys are? The zero you are looking for has to be matched up against those, no?

DaveS
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by DaveS

Numbers in the 144mm range would indicate a measurement that is between pair of outer plates at one end and a pair of inner plates at the other. Campy's 132.6mm measures between outer plates at both ends. Other brands should not vary by more than .1mm. If they do, then the rollers are smaller than the normal 7.75mm diameter, or the holes in the roller are sized differently.

Getting a length for a new chain should not be that hard. Buy a new chain and ride it once, then measure it. No rocket science to that. A measurement taken with the chain coated with factory grease will not be accurate.

There is no such thing as negative stretch. Campy chains tend to elongate less than most other brands.

Anytime you mix a measurement of elongation and then add the wear on a roller at each end, the number becomes meaningless. Better to measure individual pairs of rollers to get the difference in spacing between them and check true elongation (change in pitch) with a ruler.

0.5% increase in chain length is also a meaningless number. It doesn't insure the longest cassette life. It's more likely to insure that the most chains will be sold.
Last edited by DaveS on Tue Feb 11, 2020 3:13 pm, edited 1 time in total.

by Weenie


jesper2913
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by jesper2913

DaveS wrote:
Mon Feb 10, 2020 3:40 pm
Better to measure individual pairs of rollers to get the difference in spacing between them and check true elongation (change in pitch) with a ruler.
Do you mind posting a picture of how this is done? Not sure if it's language barrier or if I'm just to dumb to understand it.

bm0p700f
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by bm0p700f

It still way to.much effort. I left home at 8:20this morning and got back on the bike at 9:30pm. No way I am going to do this sort of shit now. That's normal working hours for me so those that manage this obviously have more time on there hands than I do.

The point 0.5% wear limit is a guide and a reasonable one as most people are not going to be as fastidious as Dave's is.

This thread is becoming a bit obsessive
Last edited by bm0p700f on Tue Feb 11, 2020 12:44 am, edited 1 time in total.

TobinHatesYou
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by TobinHatesYou

Replace your chain immediately when you can feel your shifting starting to be compromised. Wax many chains and rotate through them if you want to extend the life of your entire drivetrain. Fin.

musiclover
Posts: 109
Joined: Mon Sep 30, 2019 11:58 pm

by musiclover

DaveS wrote:
Mon Feb 10, 2020 3:40 pm
There is no such thing as negative stretch. Campy chains tend to elongate less than most other brands.
If we assume that 132.6 it is 0% of the brand new chain minus 0.5% we come to know that a new chain should be 132.05mm. How come my brand new Connex 10SX comes up at 131.6 (with factory grease removed). This is effectively less than 0.
DaveS wrote:
Mon Feb 10, 2020 3:40 pm
0.5% increase in chain length is also a meaningless number. It doesn't insure the longest cassette life. It's more likely to insure that the most chains will be sold.
It does. If one replaces a chain at less then 0.025% cassette life is even longer. But then it is less practical. Many professional riders replace chains after 1000 k, and their cassettes and chainrings last 3 years of pro use. But then again, we digress from the subject.

All
I will hopefully post some numbers from Shimano here if I am able to get them.

bm0p700f
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by bm0p700f

The small sprockets on my cassettes are toast before shifting becomes compromised.

Also one of the roads I rode down tonight was covered in farmers field mud. That's every where. Its filthy in the u.k and that knackers drivetrains.

How the *f##k* do married men like me get away with waxing chains. What are you doing dear? I'm waxing chains my darling. Are you know. Well you can sleep in the garage with your bikes then. That's how it would end in my house.

typ993
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Joined: Fri Feb 22, 2013 4:10 am

by typ993

bm0p700f wrote:
Tue Feb 11, 2020 1:01 am
How the *f##k* do married men like me get away with waxing chains. What are you doing dear? I'm waxing chains my darling. Are you know. Well you can sleep in the garage with your bikes then. That's how it would end in my house.
That's where the guy with 25 bikes sleeps.

bm0p700f
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by bm0p700f

She's quite tolerant but there are limits.

DaveS
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by DaveS

musiclover wrote:
Tue Feb 11, 2020 12:48 am
DaveS wrote:
Mon Feb 10, 2020 3:40 pm
There is no such thing as negative stretch. Campy chains tend to elongate less than most other brands.
If we assume that 132.6 it is 0% of the brand new chain minus 0.5% we come to know that a new chain should be 132.05mm. How come my brand new Connex 10SX comes up at 131.6 (with factory grease removed). This is effectively less than 0.
DaveS wrote:
Mon Feb 10, 2020 3:40 pm
0.5% increase in chain length is also a meaningless number. It doesn't insure the longest cassette life. It's more likely to insure that the most chains will be sold.
It does. If one replaces a chain at less then 0.025% cassette life is even longer. But then it is less practical. Many professional riders replace chains after 1000 k, and their cassettes and chainrings last 3 years of pro use. But then again, we digress from the subject.

All
I will hopefully post some numbers from Shimano here if I am able to get them.
Any measurement that involves rollers is NOT a measurement of chain pitch. The standard pitch is 1/2 inch, measured pin to pin. If you measure over the full length, all brands should be very close to the same. What differs is roller diameter and the size of the hole in the roller.

Any measurement of chain pitch should NOT involve the rollers. When wipperman performs chain wear tests, they measure each chain over the full length, between the pin holes. NO ROLLERS are included in the measurement of the true increase in chain pitch.

TobinHatesYou
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by TobinHatesYou

bm0p700f wrote:
Tue Feb 11, 2020 1:01 am

How the *f##k* do married men like me get away with waxing chains. What are you doing dear? I'm waxing chains my darling. Are you know. Well you can sleep in the garage with your bikes then. That's how it would end in my house.

You get away with it because it really takes less time than maintaining even one traditionally lubed drivetrain.

Buy a big crockpot. Stick it in your garage/shed. Make 5 swisher tools out of disposable wire coat hangers. Thread your chains on them. If it's your first attempt, put several blocks of paraffin in the pot. Turn it on and do whatever for several hours. Come back and dunk all 5 chains in the pot for about 10 minutes, enough to get the chains up to temp and for no more air bubbles to appear. Turn crockpot off. Pull chains out one at a time and wipe the excess with an old rag. Hang them somewhere for 15min and allow them to cool.

All in all you spend maybe 15min attending to 5 chains that will last 500km each...That's 15min for 2500km worth of riding. You never really have to degrease or wash your drivetrain after that. If I want to remove excess wax build-up from my cassettes. I just boil a kettle of water and pour it over the cassettes. This is way less work than lubing one chain per bike every single week and then periodically wiping the black gunk build up off the chain, cassette, chainrings, pulleys, etc.

musiclover
Posts: 109
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by musiclover

DaveS wrote:
Tue Feb 11, 2020 2:01 am
Any measurement that involves rollers is NOT a measurement of chain pitch. The standard pitch is 1/2 inch, measured pin to pin. If you measure over the full length, all brands should be very close to the same. What differs is roller diameter and the size of the hole in the roller.

Any measurement of chain pitch should NOT involve the rollers. When wipperman performs chain wear tests, they measure each chain over the full length, between the pin holes. NO ROLLERS are included in the measurement of the true increase in chain pitch.
It seems that we are going around in circles. Let's just say that I trust the parktool cc-3.2 which is no way different than measurement by a vernier caliper and just leave it at that.
You may prefer the ruler method - good for you.
PS and I do trust the digtal KMC tool which is just a modified vernier caliper as well.

DaveS
Posts: 2819
Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

Here's a link to ISO 9633 bicycle chain design standard. It has a drawing that shows how the chain pitch P, that defines the chain length is measured between the pins - not the rollers. It also lists the maximum roller diameter, but no minimum. There is also no mention of the roller bore diameter. That's why all brands are not the same. Also listed is the maximum pin diameter and the minimum bushing bore diameter in the inner side plates. It's the wear between the pin and bushings formed into the inner plate that causes a chain to get longer over time and creates a change in chain pitch. Wear on the roller (OD or ID) has no effect on chain pitch. It's the roller ID that wears the most, by a large margin and causes the space between the rollers to increase.

https://www.sis.se/api/document/preview/617622/
Last edited by DaveS on Tue Feb 11, 2020 8:07 pm, edited 1 time in total.

icantaffordcycling
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Joined: Wed Jan 09, 2019 5:03 am

by icantaffordcycling

TobinHatesYou wrote:
Tue Feb 11, 2020 2:12 am
Buy a big crockpot. Stick it in your garage/shed. Make 5 swisher tools out of disposable wire coat hangers. Thread your chains on them. If it's your first attempt, put several blocks of paraffin in the pot. Turn it on and do whatever for several hours. Come back and dunk all 5 chains in the pot for about 10 minutes, enough to get the chains up to temp and for no more air bubbles to appear. Turn crockpot off. Pull chains out one at a time and wipe the excess with an old rag. Hang them somewhere for 15min and allow them to cool.
You are not accounting for the countless hours spent explaining to people why waxing takes less time and is cleaner. :thumbup:

by Weenie


DaveS
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Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

Those wanting the cleanliness of wax without the crock pot should try a mixture of 1 part wax, to at least 3 parts naphtha (camp stove fuel). Apply a drop or two to each roller and allow sufficient time for the solvent to evaporate. I prefer to also add 1 part heavy gear lube or other high quality oil to the wax, before dissolving in naphtha.

If needed, the chain can be relubricated without removing the chain. I always clean the chain if it's off the bike.

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