How to Use the CC-3.2 and CC-2 Chain Checkers

A worn chain shifts poorly and wears sprockets at an accelerated rate. This video shows the Park Tool Chain Checkers in use, and how to interpret the readings.

The CC-3.2 is a go/no-go gauge designed to accurately indicate when a chain reaches .5% and .75%, the points at which most chain manufacturers suggest replacement. The CC-2 also quickly and accurately determines the wear and stretch of any chain.

For 10 or fewer speed chains, replace the chain as it reaches the 0.75% wear mark. For 11 and 12-speed chains, replace at 0.5%. Single speed chains should be replaced at 1%.

Learn more about the CC-3.2 and CC-2:

See other chain related bicycle repair procedures:

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Park Tool has been manufacturing bicycle specific tools since 1963. Based out of St. Paul Minnesota, we are the world's largest bicycle tool manufacturer. A long-term dedication to quality, innovation, and customer service has made Park Tool the first choice of professional and home bicycle mechanics around the world.

[at]

Thanks. Learned something today. I appreciate the park tool videos because I’m not very experienced with this stuff and you make it very basic so anybody can get it.

[Max]

Dear Park Tool team, I love these helpful mech videos, they are so well-designed and go over every important detail with the utmost clarity. Great products, and great videos for amateur mechanics. Thank you!!!

[fuddle]

in the shop I work in we've had bikes come in so worn that they'd gotten to the point where the chain checker couldn't fit in the chain anymore.

[BrockWarner]

Any explanation as to why 11 speed chains are worn at 0.5 instead of the 0.75 for most other chains?

[schmidtwerd]

Thank you for the amazing content, as always!

[HeatherSpoonheim]

Yeah, so this could have saved me some money had I known earlier. My chain got so worn that it jumped on the ring during a sprint - I managed to avoid a crash, but it could have been a bad one. Changed the chain and the new one kept jumping around the cassette - so had to change that too. Now I use this chain checker every time I clean my chain.

[embiggenator]

After buying the CC-3.2, I verified that I have not ridden my bike very much in the 10 years I've owned it... lol. This year's a different year though.

[shwndh]

This is why I was happier with 10 speed. Now, I have to change the chain every 4 months and chains are no longer $30, they're like $60 for 12 speed stuff. This SUCKS!

Oh, but I own the CC-2 tool and this is a great instructional video, as usual.

[texxs]

You said "Thanks for watching . . ." I say "No, thanks for teaching!"

[ERIN]

What is the reason for placing the rear stud of the CC-2 between two outer plates and the front stud between two inner plates? Thanks for info!

[johnrobinson]

Can you comment on the end of the CC-2 can also be used to see if the cassette or cranks are worn simply by inserting it into the grooves.

[nikoleta]

Hi there! Very nice video and very helpfull, too! But why in a single speed we should replace chain when it reaches the 0.1???

[Treys_Waterboy]

Do they work on the new sram t type flat top chains? If not, what tool should I use? Thanks

[anthonymelidy]

Campagnolo says that on their Record and Super Record 11 and 12 speed chains that the chain is considered worn when 6 links are 132.6mm (132.2 is new). Maybe I don't know the way Park calculates 0.5%, but according to Campy, that is 0.3%. Is it wise to rely on my Park gauge? I don't know where to get a gauge that measures over 6 links for 0.3%

[patrickjones]

My cc-2 chain checker does not come to a stop when I pus the triangle through, what does this mean?? Thanks

[raceface]

I have a CC 3.2 and I am pretty good with my chain checking. However, I normally change when the tool 'drops' into the chain link with a bit of a push (sometimes quite a bit of a push) can I keep going for a bit longer or should I change anyway. Basically the tool doesn't just 'drop in' freely. Thanks.

[Gio-Cat-Mx]

I'm confused so the higher the number, the newer the chain is. Or the higher the number, the older the chain is?

[wheeliemachine]

I’ve got a worn chain and I used the tool correctly and front pin with the marking doesn’t want to come into the outer links is the broken or the pins are damaged?
I really liked the tool but it’s not working any idea why park tool?

[joseantoniorodriguezsanche]

Can you use the 3.2 on a single speed half link chain?

[wiiztec]

So my bike has 7 rear gears but I only ever use 1 of them so does that mean I can wait until 1% to replace?