Bob Ross

I'd like to think this isn't user error -- it's not like a drop-in style chain checker is a particularly difficult tool to deploy, but I guess that's always a possibility -- so I'm kinda baffled by the results I'm getting.

The chain on one of my bikes has ~3,200 miles on it. The cassette on that bike has over 6,200 miles on it.
Cassettes I can sometimes get more life out of...but usually only if I've been changing the chains every 1,500-2,000 miles.
So purely based on the accumulated miles, I fully expect that I'm due for at least a new chain, if not also a new cassette.

And sure enough, the drivetrain has been behaving exactly as I would expect it to when it's time for at least a new chain, if not also a new cassette.

So far so good, right? Just change the freakin' chain (and maybe cassette) Bob and be done with it!

But I have this Park Tool CC-4 chain checker, and on a whim I used it to check this used-for-3,200-miles chain.

No wear. Not .50%. Not .75%. None.

Da hell?!?!

Is there any possible way to (mis)deploy a CC-4 and get false-positive readings? Or, is it common to have a chain that doesn't register any wear on a CC-4 and yet shifts like crap, because it's actually got ~3,200 miles of use on it? Is this chain checker tool useless, or am I a tool?

Thanks.

Bill Kapaun

Typically, they tend to show more wear than actual.
Mine show's .25% on a new chain.
I use a tape measure and check a 3' section. I use the 1" & 37" marks to avoid an often inaccurate "hook end".

shelbyfv

Just in case....

Bob Ross

Thanks. That confirms that I'm using the tool correctly.

Rolla

You’ve probably done this, but be sure to check the chain at different sections; they don’t wear evenly across all the links.

79pmooney

Now there's the old fashioned and labor intensive process of measuring 12 pairs of links to see how much whey have stretched beyond 12". Requires a steel ruler marked in those ancient inches. 12 1/16" and the chain has done its job. Replace now and the next one should run just fine.

I always use a ruler or tape measure. Consistent, reliable and easy to replace for minor bucks when it chooses to hide in a creative place.

Being snarky here but I simply won't use a chain checker until I've calibrated it against known chains and that's enough work that why bother?

DaveSSS 

I have a length of scrap tape measure with a hole drilled through the 10 inch line that fits over a pin in my work bench. I can easily check the full length for true elongation. Only check a chain after cleaning. I alternate the use of several chains so I don't have to toss them prematurely to avoid new-chain skip.

Some chains, like those from Campy may show little elongation, even after 6,000 miles, but the roller and side clearance wear can be huge. Run one that long and you'll get new-chain skip. Use calipers to check the increase in length between rollers. Measure between the outer plates. A new chain will check around 1.200. 1.220 is a lot of wear.

oldukbkr 

A worn cassette can cause skipping regardless of the condition of the chain. So it might be that your chain has not worn enough to fail the chain checker but the cassette needs replacing, especially if you have replaced the chain previously.

ClydeClydeson

I have only had poor results from 'chain checkers' - esp. 0.75% wear reading on chains new from the box. I don't know if it is a design issue or if the manufacturing tolerances on the tool are crap.

THe more reliable and simpler method is a ruler to measure 12 links (edge of pin to edge of pin) against 12 inches.

Although I generally do prophylactic chain replacements after a few 000s of kms (maybe at the start of the season or some other arbitrary point in time) without worrying about measuring anything, and then a 'functional' test for cassette wear - if the chain skips under load or otherwise doesn't mesh well with the cassette then the cassette is worn and needs replacement

jccaclimber

Unlikely, but just to be sure, is the chain too worn to pass the tool rather than not worn enough? I have a Park CC3.2 (and a ruler). Every now and then I run into a chain so worn that the tip on the tool hits the next roller back instead of slotting in between rollers, implying a pass when there should not be.

Bob Ross

Doesn't seem to be. And using a steel straightedge ruler and measuring in several locations along the chain, the pins are still almost exactly at 12.00"

zandoval 

Yep... Tape measure will give you a better idea of how much wear you have. I also once had a KMC chain that had more wear/stretch over a section of just 10 links. The rest of the chain was fine. I have no idea if it was manufactured that way or if I did it. The chain tools and the tape measure will not detect worn or misadjusted cogs and chain rings but, you already know this...

gearbasher

I have 3 different chain checkers. My eyes just aren't good enough for the ruler method anymore. The three I have are :
ProLink This one shows 100% wear on new chains. So it's useless
KMC digital. This one reads very little wear on worn out chains, Again useless.
Park CC-3.2 This one is the most accurate and my go to checker.

As someone mentioned above, check the chain in various places. I've noticed if you straddle the quick link with the checker, the chain shows more wear than other areas.

Koyote

Yep.


And yep again. If you replace the cassette, throw on a new chain at the same time.

deacon mark

I don't use chain checkers I use a machinist ruler and measure much better. I generally get 7000-8000 miles on a Shimano 11 speed with little wear and at least 20,000 on a cassette. I do keep the chain clean and I normally do not ride in the rain and on decent roads. I live in the flatlands also but chains can last some folks a good long time. If you are a spinner and take reasonable care a chain should last at least 3000 miles. I suppose if you are big and climb they wear much fast but I don't think you need to do a thing. Except throw away the chain checker and use a good machinist ruler.

79pmooney

Bob, I"m curious. You're cassette was 3000 miles old when you put this chain on. Did it shift well then? Also, did you start the cassette with a new chain 6200 mils ago? I ask because neither of those mileages are especially far unless you are strong/big/ride hard hills. Now, riding small ring, small cog combinations increases wear quite a lot as does large crossovers. Dirt and low lubricant are also chain killers. That said, I have never been meticulous re: chain cleaning,spend the vast majority of my time on the 39-42 tooth chainring and use the entire cassette with that chainring. (I also do not use index shifting. It may be that my shifting adopts and I simply never notice.)

Shimagnolo

I wasn't even aware of the CC-4, but it is good to see that Park has finally followed Pedro's in mimicking the design of the Shimano TC-CN41.

Bob Ross

To the best of my recollection everything shifted fine when I put this most recent chain on, it's only been in the past couple weeks that I've noticed things getting sloppy. And yes, I always put a new chain on when I put a new cassette on.

Don't consider myself particularly "strong" or "big" but I do often ride hard hills. I'm pretty sensetive to -- though not dogmatic about avoiding -- cross-chaining. And I wipe down my chain with a paper towel after every ride, and keep it lubed at appropriate intervals.
I agree, ~3,000 miles isn't especially far for a chain's lifespan, but I'm usually pretty happy if I can get that much out of one.

Drew Eckhardt 

1. Increased flexibility from side plate wear can degrade shifting although a chain has not elongated
2. Some chains elongate slower than others, notably Campagnolo. I replace mine after 4500 miles because front shifts are slowing although they're just reaching 1/32" of elongation over 11".
3. $1 rulers are more accurate than most chain checkers because they measure pitch change without error from roller/bushing/pin clearance