measuring chain wear

[belgiangoth]

Just followed the advice on sheldon (etc) and found that 12" measures from one rivet to half way between the links, or 1/4" wear. Surely that's not possible as the links can't be that thick to start off with? Any thoughts what obvious thing I'm doing wrong?

[philg]

What are you using to measure? - a tape measure may not be that accurate; a metal engineering ruler is best.

Or use the Park chain measurer, cheap, simple & accurate (others may disagree)

If it really is 1/4" you have a very worn chain!!

[belgiangoth]

Does it make a difference that it's a track chain, so 1/8th?

[Mike McGeever]

Thinking about changing your chain?
You will need to eventually.
Modern speed links are brilliant.
So
Knock a masonary nail or cut head off "wire" nail after you have knocked it into say, the garage doorframe.
Must be horizontal!!
Hang old chain and new chain on the nail.
It is now very easy to measure total wear- NOT STRETCH-cos if it is stretch then they have made the chain from wrong material.

[BigG]

+1 for that. Hangong the chains is the easiest and most accurate way of checking their length. Half a link extension is acceptable; three quarters is not. This applies more or less equally for any normal chain length of108 to 116 links.

[Mick F]

Half a link over the length of the chain?
Sorry, there's no way that I would have a chain worn even half a half of a link.

I use a 39" steel rule, and I retired my last chain when it was a eighth of an inch worn at 39".
6,000miles of use.

[vorsprung]

I used to use the "measure with a ruler" method but found it a bit imprecise and faffy. I missed a very worn chain before a long audax with bad results The park chain tool checker is a lot easier

[belgiangoth]

Compared the chain with a new one on another bike, yes, massively stretched.
Mick, I am not surprised that you take better care of your chain than I do. I am shocked that my bike did not break due to poor chain wear. Oh well, it's been about 6 years...

[BigG]

Half a link over the length of the chain?
Sorry, there's no way that I would have a chain worn even half a half of a link.

I use a 39" steel rule, and I retired my last chain when it was a eighth of an inch worn at 39".
6,000miles of use.

I think that the Park tool has a go/no-go point at 0.75%. This is slightly more wear than three-quarters of a link over a full chain length. I change after half a link wear on 114 links. This is about 0.43%.

[belgiangoth]

Not too surprised to be fair, as the chainring was proper knackered. On the other hand the cogs look fine, which confuses me.

[Brucey]

On the other hand the cogs look fine, which confuses me.

appearances may be deceptive....1/8" chains are cheap enough to sling in the bin once every few months if needs be; the last ones I bought cost £2.40 each or something stupid like that (Parker mail order; see 'cheap as chips chains' thread)

cheers

[Aushiker]

Or use the Park chain measurer, cheap, simple & accurate (others may disagree)

They do See http://pardo.net/bike/pic/fail-004/000.html

Andrew