Crazy Cyclist

also what is the average cost of a new chain? I ride a mountain bike.

mtbkanata

Two ways, you can use a chain gauge (www.parktools.com), or you can get your chain and hang it from a nail, and a new chain beside it... when your old chain is about a link longer, it's time to replace! Chains are really cheap ~$20, but don't forget that the drivetrain all wears together, and depending on how worn/old your chain is, you may need a new cassette, and new chainrings (usually only the middle one). Anyway, just something to think about.

Joe

KleinMp99

12 links should be exactly 12 inches, measure the chain with a ruler. If its far from that, then replace it. $12

Pete Clark

I stole this from Sheldonbrown.com/chains.html

Sheldon Brown's website is a trustworthy source.

Measuring Chain Wear
The standard way to measure chain wear is with a ruler or steel tape measure. This can be done without removing the chain from the bicycle. The normal technique is to measure a one-foot length, placing an inch mark of the ruler exactly in the middle of one rivet, then looking at the corresponding rivet 12 complete links away. On a new, unworn chain, this rivet will also line up exactly with an inch mark. With a worn chain, the rivet will be past the inch mark.
This gives a direct measurement of the wear to the chain, and an indirect measurement of the wear to the sprockets:


If the rivet is less than 1/16" past the mark, all is well.

If the rivet is 1/16" past the mark, you should replace the chain, but the sprockets are probably undamaged.

If the rivet is 1/8" past the mark, you have left it too long, and the sprockets (at least the favorite ones) will be too badly worn. If you replace a chain at the 1/8" point, without replacing the sprockets, it may run OK and not skip, but the worn sprockets will cause the new chain to wear much faster than it should, until it catches up with the wear state of the sprockets.

If the rivet is past the 1/8" mark, a new chain will almost certainly skip on the worn sprockets, especially the smaller ones.

mtbkanata

Pete: Do you have that in Metric for us Canadians?

Joe

Pete Clark

1 inch = 25.4 mm

Inoplanetyanin

Geez, this simple task is written so complicated as it was attempt to explain Shreidenger's equation...

chip

Grab both hands on chain close together and try to push and pull apart...if there is play you need a new chain

Pete Clark

I think one important thing to determine is how much a chain has worn. A chain that wears too far will wear out the sprockets, and you will be facing a repair equivalent to several chain replacements.

bmw_maniac

12 inches = 30.48cm / 304.80mm

ask ME if u got any other conversions to do!!

mtbkanata

You can pull the chain off the cassette with your hands to see if both are worn. under regular tension, you should not see light through the chain and cassette (Pull the chain right off). Just pinch one link and pull, see how much stretch you get!

Joe

lotek 

sigh,

where's D*Alex when we need him?

SheldonBrown overcomplicated? I think not!

Marty

Inoplanetyanin

Trying to sound professional and use "smart words".

How to make a peanut butter sandwitch.
Two main components should be included in preparing such an important source of fiber as a peanut butter sandwitch, which consists of carbohudrates- nutritious peanuts, bread. On the structure with four legs, and usually made of wood (table), a peace of food described above (bread) is put in such a way so it will not fall on the floor.............

this is my point.

Inoplanetyanin

If you got a clear image and understood everything from the first time reading of this text - you are genius...

posted above:

The standard way to measure chain wear is with a ruler or steel tape measure. This can be done without removing the chain from the bicycle. The normal technique is to measure a one-foot length, placing an inch mark of the ruler exactly in the middle of one rivet, then looking at the corresponding rivet 12 complete links away. On a new, unworn chain, this rivet will also line up exactly with an inch mark. With a worn chain, the rivet will be past the inch mark.
This gives a direct measurement of the wear to the chain, and an indirect measurement of the wear to the sprockets:


If the rivet is less than 1/16" past the mark, all is well.

lotek 

uh, I hate to burst your bubble (well not really) but
Sheldon Brown has probably forgotten more about every
aspect of cycling than you or most of us here will ever know.
Yes he is a professional.
what is unclear in his instructions? he tells you exactly
how to measure the chain, and when it needs to
be replaced.
I would prefer to be treated as having a modicum of
intellegence than have Sheldon dumb down his
website.

marty

Pete Clark

It seemed pretty clear to me...