Bicycle Mechanics - Measuring chain wear - unusual question

Hi all. With temps below 20 degrees, I have time to ponder my bike...Hence this question that has long nagged at me.

I use a Park CC2 chain checker tool, which measures wear between the rollers: http://www.parktool.com/products/detail.asp?cat=5&item=CC-2

Even if I use the chain almost until the checker reads 1% (=replace), I still have no perceptible chain stretch as ascertained by the ruler method (measuring twelve links).

So here's the question: do the rollers wear from constant contact with the teeth on chainrings and cogs, even without the chain "stretching"? In other words, if these two measurement methods give different results, which should I use? I'd hate to replace chains more frequently than necessary, but would also hate to wear out cassettes more frequently than necessary, too.

Thanks...

So how does your chain checker work on a brand new chain?

I don't put a lot of faith in chain checkers because they sample such a short section of chain. For my personal bikes I rely on the 12" ruler method. I think that chain checkers are more appropriate for shop work because they give the customer an objective, easy-to-read indication that he needs to buy a new chain. I think that the one that I have tends to sell chains a little sooner than is necessary too.

So how does your chain checker work on a brand new chain?

I don't put a lot of faith in chain checkers because they sample such a short section of chain. For my personal bikes I rely on the 12" ruler method. I think that chain checkers are more appropriate for shop work because they give the customer an objective, easy-to-read indication that he needs to buy a new chain. I think that the one that I have tends to sell chains a little sooner than is necessary too.

Huh?

The customer would never be using any shop tools from the shop.

I don't much care for chain checkers, I just use a ruler.

Huh?

The customer would never be using any shop tools from the shop.

You put the chain checker on the chain in the customer's presence. "Oh, oh, look here. You need a new chain."

I guess in Canada they'd say "Oh, oh, look here eh? You need a new chain eh."

I guess in Canada they'd say "Oh, oh, look here eh? You need a new chain eh."

:p :p

The ruler only shows stretch not lateral wear.

I don't much care for chain checkers, I just use a ruler.

You put the chain checker on the chain in the customer's presence. "Oh, oh, look here. You need a new chain."

I guess in Canada they'd say "Oh, oh, look here eh? You need a new chain eh."

Not all Canucks end every sentence in "eh"... it's an eastern thing.

This one uses a ruler as it is more accurate.

So how does your chain checker work on a brand new chain?

I don't put a lot of faith in chain checkers because they sample such a short section of chain. For my personal bikes I rely on the 12" ruler method. I think that chain checkers are more appropriate for shop work because they give the customer an objective, easy-to-read indication that he needs to buy a new chain. I think that the one that I have tends to sell chains a little sooner than is necessary too.

i check the chain in several places but let's face it when you've been doing this as long as some of us have either a chain checker or ruler or usually a best guess will work :eek:.

ed rader

i check the chain in several places but let's face it when you've been doing this as long as some of us have either a chain checker or ruler or usually a best guess will work

I doubt using a chain checker in several places helps very much. To me the issue is measuring wear over a 3" length vs. a 12" length. When you're trying to identify 1/2% to 1% wear I think that the longer distance is always going to be more reliable because you're trying to measure a tiny length. My personal experience with using chain checkers hasn't changed my opinion.

You put the chain checker on the chain in the customer's presence. "Oh, oh, look here. You need a new chain."

I guess in Canada they'd say "Oh, oh, look here eh? You need a new chain eh."

Gee, that's really funny. I've never heard that one before. You should do stand-up.

I use a ruler.

EDIT: Gee, that's really funny, eh. I've never heard that one before, eh. You should do stand-up, eh.

I use a ruler, eh.

With the CC2 you need to be very careful to not apply too much pressure, this could give you an inaccurate measurement. Just take out all of the slack. Using too much pressure can bend the tool's small pins.
One expert on another forum says that it is possible to wear the rollers faster than the rest of the chain and that you really need to check for roller wear as well as chain stretch, that's what I do. I also replace chains at .75 with the CC2 or 12 1/16 inches over any 24 pin interval using a good steel ruler.

Al

The ruler only shows stretch not lateral wear.

A chain checker shows lateral wear? http://planetsmilies.net/confused-smiley-17478.gif

Each time I remove the chain for cleaning I stretch it on a table and measure the full lenght.