Where does a chain actually wear?

[MudLark]

The conventional view is that a chain wears primarily as between the roller and the pin. But I wonder if this is correct? Disassembling several different makes of chains, I have noticed that the roller doesn't seem to actually rest on the pin itself or to make direct contact with it. Rather, the roller seems to rest on shoulders pressed into the inner plate metal. That seems to be the only contact point. If I am correct  then that would also be logical  in a bicycle as the smaller contact surface would likely serve to reduce friction (albeit at the cost of greater load on the bearing surfaces). But if I  am correct, then it also raises some questions about where the wear in fact occurs* and what one should be aiming to achieve with lubrication (not that one might actually do anything differently).

*Let's accept that chains wear in several different ways, including between plates and between inner plates and pins. Here I'm focused on what happens with the interface between the rollers and the various other components.

[Eldron]

https://bike.bikegremlin.com/3306/bicycle-chain-wear-elongation/

[SwissVan]

Time for a JB masterclass, he covered this topic pretty well in the past, should have been pinned in the tech forum…. Maybe it was 🤨

[Alouette3]

Pop off an old, well used master link and you can often see the wear in the pins

[David Marshall]

JB published a book on the subject.

https://www.amazon.com/Everything-need-about-Bicycle-Chains-ebook/dp/B00O46YUW0

Tech Q&A used to be a great Friday thread.  Miss him. (That and couches in the classifieds.)

[MudLark]

3 hours ago, Alouette3 said:

Pop off an old, well used master link and you can often see the wear in the pins

So there's a case in point. When you pop out the master link, the rollers don't fall out. Why? Because they don't rest on the pin but on the shoulders I have referred to.

[Robbie Stewart]

Boet, you need to sort your sleep patterns out. How on earth does one come up with these ideas at 4 in the morning 🤔

[Knersboy]

My chain only wears when it is on my bike

[dasilvarsa]

Inner plates have grooves for holding the Rollers in place.

Pins Hold the Chain Together. (The Pin Never Touches the Roller).

Wear is between Rollers and Inner Plates.

If you Lube your Chain "Every Ride" or Every 30Km . Your Chain will Last Very Long.

 

Edited April 4, 2022 by dasilvarsa

[jcza]

I thought it stretches? 

[Eldron]

58 minutes ago, jcza said:

I thought it stretches? 

Sat that is a mighty big spoon to be stirring *** 🙂

[jcza]

14 minutes ago, Eldron said:

Sat that is a mighty big spoon to be stirring *** 🙂

Can you remember the arguments? 🤪 

[Eldron]

1 minute ago, jcza said:

Can you remember the arguments? 🤪 

Vaguely.... I think the metallurgist in me died many times during those "heated debates".

[TheoG]

[throttles]

2 hours ago, TheoG said:

I’m surprised nobody asked in 2hours..  but here I go..

Where is picture 7??

 

[TheoG]

Just now, throttles said:

I’m surprised nobody asked in 2hours..  but here I go..

Where is picture 7??

 

In here as posted by @Eldron:

https://bike.bikegremlin.com/3306/bicycle-chain-wear-elongation/