good or bad chain

[zaku]

how do we check if the chain is still good or should be replaced? is there any indicator on the chain that shows the wear? or any tests we can do to figure it out?

i know there's a method we can check by measuring the length of the chain. but how about a method without removing the chain?

[sideshow_bob]

you measure the chain length without removing the chain. there is a little $10 tool that measures it. you simply drop it in and it'll give you a measure of 50 and 75% wear usually. takes about 2 seconds.

--brett

[CAMPYBOB]

Chain 'stretch' tools can give false or inaccurate reading on chains from varying manufactures.

One of the easiest ways of determing how worn a chain has become is simply to measure it from pin-to pin over a one foot distance. The most often quoted acceptable stretch dimension is 12-1/16" maximum. 12-1/16" to 12-1/8" is replacement time. Use only an accurate steel scale with the chain pulled tight.

[threaded]

I tend to wax my chains so I just wait until I crank the pedals and there's a grinding noise without much forward movement, then replace the chain ring, chain, and rear cogs all at once.

Sometimes I will wait a couple of weeks or so, just to watch the look on peoples faces when I set off from the lights, IMHO also good for training souplesse as well. Well, they're better excuses than saying I'm a cheapskate. ;)

[p38lightning]

I'm with Campybob, there is no need for a special tool, a good ruler does just fine. It's the top run of the chain that you measure.

[dhk2]

Chain 'stretch' tools can give false or inaccurate reading on chains from varying manufactures.

One of the easiest ways of determing how worn a chain has become is simply to measure it from pin-to pin over a one foot distance. The most often quoted acceptable stretch dimension is 12-1/16" maximum. 12-1/16" to 12-1/8" is replacement time. Use only an accurate steel scale with the chain pulled tight.
CB, I've used it on SRAM and Shimano with good results, and don't see why it wouldn't work for all. Aren't the dimensions of chain pitch and rollers set to a close industry standard? My chainrings and cogs expect the same pitch and roller diameter, regardless of what brand of chain I use. If one manufacturer has rollers on the small diameter side, or the pitch on the long side, that would just mean his chain "wears out" faster in my mind.

The gauge does measure wear on the rollers in addition to just the wear on the pins that we measure with a rule; perhaps that gives a different result, but between the rollers is really where it counts anyway.

[CAMPYBOB]

http://www.velonews.com/phorum3/read.php?f=2&i=134903&t=134903

http://www.fagan.co.za/Bikes/Csuck/STRETCH-MEASURE.htm

Yes, all chains are manufactured the same 1/2" pitch standard. However, design clearances and manufacturing tolerances vary...not considerably, but enough that significant tool readings can occur over the very short length of chain being measured.

Eh. I'm giving up. Scientists will soon be along to correct the technical errors of the methodology and suggest we all run heavier chains and finish 4 seconds apart after 100 miles of hills.

My original post was not meant to disparage the manufacturers and/or users of chain stretch tools, just to point out possible read errors.