How far to push chain wear

[Ajax Bay]

Run it till it snaps then new cassette and chain

She went over the bars, face first within a second.

At the very least, inconvenient if your chain 'snaps' during a ride: at worst dental and facial (or undercarriage) damage. What do your clubmates in Uttoxeter think of this when it happens on a club ride? An opportunity for them to wait while you demonstrate your prowess with the chain splitter and quicklink you carry, I presume.
Skipping will likely occur on the most used sprocket flagging up the need for action (replacement) This sprocket is invariably one in the middle of the block and hopefully not one that you're in when standing up and putting 'powahh' through. Skipping on a sprocket when seated is (ime) disconcerting rather than a catalyst for 'fast motion'.

 

[KnackeredBike]

As I have already said on here, I have only ever had one chain snap (as a kid) despite never cleaning them, never changing them until they are thoroughly buggered, chucking on some cheap lube from time to time. I honestly think some people are acting as if bushingless chains were never invented, certainly cleaning them every two hours seems like a lot of work for very little gain

 

[Vegan1]

Why not mention them? What pitfalls are there and how is shifting and power transfer affected by a worn chain?

View: https://www.youtube.com/watch?v=qinJjb8_nEs

 

[Yellow Saddle]

View: https://www.youtube.com/watch?v=qinJjb8_nEs

The man is confused. He talks about stretch and wax. Whilst that is good for beauty treatments, it doesn't work with chains. Further, he doesn't address power transfer, only frictional losses which he exaggerates. You omitted to answer my question. How does chain wear affect shifting?

 

[Ian H]

I admit to being entirely unscientific about this. I normally replace chain and block when the changing becomes noticeably less precise, and rings when they look severely worn.

 

[ianrauk]

I admit to being entirely unscientific about this. I normally replace chain and block when the changing becomes noticeably less precise, and rings when they look severely worn.

You and me both.

 

[andrew_s]

From the thread, @Hugh Manatee @MontyVeda @Ticktockmy are with you on the 'ride till it skips' philosophy - not sure about @andrew_s
Provided one is prepared to replace chain and cassette together each time, with the implicit doubling/tripling of expenditure, that's an option a fair proportion take, I surmise.

I ride it until it skips too.

As I use 8-speed, and buy cheap where possible, the cassette doesn't cost much more than the chain. The skipping point is at about 5 times the mileage of the chain checker point, at least. I see no point spending more on chains to protect the cassette.
("skipping" includes any other problem that makes me decide a change is required)

When I worked out my mileages & wear rates, I decided it would be cheapest to have 3 chains and rotate them every 500 miles or whatever until everything was scrap, but ICNBA.