I just bought the Park pliers for opening and closing quick-links, because the kid's new bike came with a SRAM 12-speed and their version, which I think they call a power-link.

I then noticed Shimano sells a version of their XTR chain (which I use) that has a (presumably genuine) Quick-Link for an extra $3.

Is there any downside to this? Does it weaken the chain? Does it wear stuff out any quicker? Does it shift less smoothly, cause infertility, projectile diarrhea, cancer, heart disease, premature Alzheimer's, or other potentially negative side effects?

I broke my ankle a few years ago and am a bit irrationally paranoid about snapping a chain when I am climbing a steep hill.

If there’s a down side to using a quick link, I have yet to discover it. Most of my bikes have KMC chains with their “Missing Link” connector and I’ve never had a problem with them.

Only downside for me is finding the other half when I want to put the chain back on. One half is always missing. It is eventually found hiding somewhere, but it never seems to be where I swore I put them.

John

I keep an old cat food can on my bench with a slosh or two of mineral spirits in it. When the quick links come off they go right into that can. I, then, know where both are and they come out clean. Down in the dungeons of my LBS all the new SRAM and KMC chains now come with quick links. They seem to believe in them and I've had no problems. I'm using them on 10 bikes.

They have worked flawlessly for me. Besides the new chains have swaged pins, and I dont trust them not to come loose if they are pushed out and then back in.

The only time I didn't use one was when I replaced my wife's chain with a new shimano that didn't come with one. Never had one fail. or cause erectile dysfunction.

I always now use quick links, so easy to split chain to remove clean etc, never had one fail, the Park chain tool is great. I think 1 am more likely to have a failure pushing out & replacing pins, if however if its an older steel bike I'm rebuilding then I use the original pins to keep it more in character.

The only issue with quick links is to ensure you use the correct type link for the chain speed, its always marked on the little packets, as they come in different ranges.

Add me to the line of others who endorse quick links. Very convenient to use. 'Never had a failure.

Dean

Another supporter of quick links. Over 100K miles without failures. I have even used the same link on successive chains. I think 9-10K miles including many removal/re-installs is what I got out of one before deciding to trash it after the pins started showing wear grooves. I would guess that yes, it's probably the weakest link in the chain but proven to be strong enough. No difference in performance or extra wear. No medical issues that I can think of. Just look closely when you install them to make sure the link is snapped together properly as I have seen when showing non-mechanical friends how to install them that sometimes they have difficulty getting both pins in the slots properly. Easy to correct if they get it wrong the first time though.

No downside. I've been using them for 15 or 20 years.

Shimano DA/Ultegra/105 chains now come with Shimano quick links. No more pins.

The correct KMC part for 11 speed shimano chains is CL-555R (reusable) and CL-555 (non-reusable). The difference is not apparent and I've reused the non-reusable versions many times.

I've had a SRAM 11-speed PowerLink install tight. It loosened up after a mile or so but I try to avoid them.

SRAM, KMC and Shimano all work with Shimano chains.


-Tim-

I've used Craig (the original "quick link"), KMC, SRAM and Wipperman Connex master links all with great results. The Shimano chains I have in inventory still use their joining pin so i have no experience with their master link.

Master links for wide chains have 3 parts.. those do have their PITA issues ,
due to the little fork spring clip that holds the side plate with 2 holes , snapping on to both pins on that one.

The only disadvantage of quick links is that most 10-11-12 speed ones are only specced to be used once. This can reasonably be extended to a handful of uses, but I've seen them literally fall apart after removal from a worn chain.

The new Shimano chains with quick links are nice. I wouldn't worry about it. No other option for 12 speed.

Those are limited to single speed and department store bike chains and motorcycle chains. I don't think any master link for current derailleur bike chains are of that design.

Of Course not , but the 'master link' is Old stuff , the 2 piece keyhole locking ones recent.

Another supporter of the links. I used SRAM chain and links for several years and the last couple of years I have been using KMC's. Knock on wood, no problems with either.

No significant downsides. Supposedly the pins on the master link wear slightly faster than normal pins, maybe.

Thanks, everyone.

Does "single use" mean replace when you replace the chain, or does it mean replace each time you open the chain (which would defeat the purpose, from what I can tell)?

By single use, they do mean to replace every time you open the chain. In practice, people frequently reuse them--this requires a bit of good judgement--if it doesn't take any force to close, it's definitely not in good shape. This varies a little--SRAM says to use a new link every time with 10-12sp, and that you can reuse 8 and 9 speed links. KMC says don't reuse 11 and 12 speed links, good for 10sp. Shimano's new 11 speed link is officially not reusable. Wipperman/Connex advertises reusability for all their links.

I think the real point of them is that it's much harder to mess up installation than with a pin, which can be under or over driven. Also, even if you use a new link, you're not recutting the chain and pressing in a bunch of different pins.

I reuse them several times, SRAM & KMC until they are noticeably easier to disconnect, then replace.

Outer plates get thinner and thinner, as the number of "speeds" increases. That means the marked part in the picture is thinner for 10, 11, 12 than it is for 7, or 8 speed chains. Some manufacturers recommend not re-using quick links with 10+ speed chains, probably because the safety margin is lower with such thin outer plates. My guess (and experience) is that, like others have said, with some common sense, even 10+ speed quick links can be reused as long as they lock securely (not too easily).
... although, common sense also tells me there's no need to go with more than 8 speeds unless racing.

That's why it's called a "missing" link.

I'm also paranoid. But, I've been using them for years and never had a problem. Except for trying to locate it when I want to open the chain. The eyes ain't what they used to be.

KMC links up to 10 speed can be re-used. From their site:

HOW MANY TIMES CAN THE MISSING LINK BE USED?

The Missing Link on chain models X11SL and X11L can not be reused. All other Missing Links can be reused between 2-3 times per life cycle of the chain. If you purchase a replacement chain, the used Missing Link should not be reused and is not interchangeable. Missing Links offer riders ease of maintenance and quick chain replacement when there is an emergency on the road or trail.

I just bought a card of 6 KMC links (before I read your post, now I wish I looked harder for the reusable version ). Here is a picture of the top of the package. Notice that they call out the details (the "Safety Lock" features highlighted in red on the drawing) that make the link non-reusable. I don't know what the reusable version looks like, but I do intend to try to reuse these (at least the non-reusable one that came with my KMC chain).

Generally accepted best practice is to replace the quick link when you replace the chain. If the chain is to be removed and reinstalled, for cleaning for example, then the same quick link is reused with the chain. The link goes in the recycle bin when the chain is retired.

I'm not saying that anyone should do this, only that this is what most people do, including myself.

Personally, I've never purchased the reusable version.


-Tim-

I've used 9- and 8-speed quick links for a long time. First SRAM and more recently KMC. Cost-effective when bought in multiples on a card. I try to always have a couple in the emergency repair stash I carry on all rides. Came across a tandem team on the side of the road a few years ago who had dumped their chain on a climb and had lost half of a quick link in the process. I was able to gift them one of my spares to get them back on the road.
I'm in the habit of replacing the link when the chain is replaced.