Jim’s Tech Talk
By Jim Langley
Before getting to the technical Q & A, I goofed last week and didn’t show you Bruce Ross’s favorite bike bling saddle. It’s this tri-color masterpiece by Busyman Bicycles. Nice, huh?
Now, to get on with the show, an important question (read to the end to find out why it’s important) came in from retired RoadBikeRider founder and Team RAAM record holder, Ed Pavelka. Since he handed over the RBR reins almost exactly eight years ago, Ed, now 72, moved south and still rides lots, averaging 12,000 miles a year. “It’s more fun during Florida’s winters than in its long hot summers,” he notes.
Ed’s Important Question
Ed wrote, “I have a question that you may have already covered for RBR or perhaps somewhere on your website. It’s about SRAM PowerLinks.”
Editor’s note – SRAM PowerLinks are special links provided with new chains. Sometimes called “quick,” “connecting,” or “master links,” they are used during chain installation to join the ends of the chain without tools. SRAM and other chain companies make these special links. You can see how the SRAM links work in the photo. For the model of chain Ed is asking about, SRAM calls the link the PowerLock Chain Connector 11-Speed.
Ed continued, “For more than a decade my main bikes were 9-speed and I ran SRAM PC-971 chains. I loved the PowerLink feature and used it to easily remove chains for cleaning and lubing. I never saw a warning against using a PowerLink more than once and I never experienced a chain problem from a reused link.
“Now I’ve upgraded my steel and titanium Independent Fabrication Club Racers to SRAM eTap and 11-speed drivetrains with Red22 chains. According to SRAM, the PowerLock can be used just once — for initial installation. That is, if the chain is removed for any reason a new PowerLock must be used to rejoin it. Find the PowerLock on Amazon.
“Why can’t a PowerLock be reused? I lube with Rock & Roll Extreme so I never need to remove a Red chain for cleaning. But I do remove the chain sized for my 11-26 Florida cassette when I put on the 11-36 for annual cycling vacations in the hills of Pennsylvania and upstate New York. Then I’ll remove that longer chain when I return home and put the shorter one for the 11-26 back on.
“This means I could reuse a given PowerLock several times during the life of the chain. If I do this instead of installing a new PowerLock each time, what’s the problem? After all, the PowerLock is being pulled tight by the direction of chain travel. How could it fail?
“I did snoop around online and found a pretty even divide — some people say the 11-speed PowerLock is reusable, no problem; others say it’s strictly for one-time use. Which is correct?”
Answer
Great question, Ed! I wasn’t 100% sure myself, because I have reused about every connecting link going. So I decided to go straight to SRAM for an answer. I reached out to Road Marketing Technical Rep, Nate Newton through SRAM’s online link
What Nate wrote back surprised me because like Ed, I assumed that a connecting link will hold the chain together no matter what. It turns out that’s completely wrong. Read Nate’s explanation — I put the important part in bold:
“Our 10- and 11-speed PowerLocks are one-time use only, because as they are removed, there’s enough deformation at the interface where the pin clicks into the plate that a second install will not be as secure. The potential failure mode is the PowerLock opening on its own when the chain goes slack. You can hear and feel that on initial install, the PowerLock installs with a loud click, and requires a tool to re-open. But on subsequent installations, it installs silently and with no effort, and can be re-opened by hand.”
I wanted to also get an opinion from an impartial tech expert, so I sent the same question to one of my most trusted industry friends — someone with extensive current experience testing all brands and models of connecting links. He prefers to remain anonymous.
What my tech guru says is almost the same as what SRAM said, and he shared some failure examples:
“Jim, I STRONGLY urge you not to recommend your readers reuse those links. Some may weigh in saying they have reused them without issue but it truly isn’t a question of IF they fail but WHEN, once you go off schedule and choose to ignore the manufacturer’s recommendation.
“The failures I have seen in testing are in two places. First, at the pin / outer plate junction. On one I had fail on my bike, I literally saw the pin fall out of the outer plate on the side where it was (previously) permanently fixed at the factory.
“With the master links like SRAM’s you also ‘feel’ the link positively snap into position. As the link is reused the positive engagement disappears as the engagement hole becomes enlarged and elongated.
“This creates a second point of potential failure especially if a rider hits a bump or has a sticky freehub that detentions the chain (think forces that replicate pedaling backwards) allowing the pin in this now oversized hole to partially or fully fall out while riding.
“If that happens, the unsuspecting rider re-tensions the chain only to experience a very sudden failure. And, as I’m sure you’ve seen or perhaps had happen to you, this usually results in a bad crash. So, again, please advise your readers for their own safety to not reuse the links.”
I’d like to thank Nate at SRAM and my anonymous expert for clearing up this uncertainty.
A Link You Can Reuse
As Ed mentioned, having a link you can open and close more than once comes in very handy for cleaning and changing chains. It’s also smart to carry such a link in your repair kit for easy repairs should you break a chain on the road (some roadies call these links “chain patches” — always liked that name).
While we now know that the SRAM PowerLock is not designed for reuse, there is a popular connecting link that is — Wipperman’s Connex link. It’s said to work on any brand of chain. Learn more: https://www.connexchain.com/en/connex-connector-bike-chain.html. They are available at bicycle shops and Amazon.
Ride total: 9,122
The only problem us that Wipperman, in turn, claims non-reusability of the 11-speed ConnexLink (unlike to their 8-, 9- and 10-speed models).
A funny thing is that I cannot find this warning regarding non-reusability on the Wipperman anymore.
I had a Wipperman 10 speed link fail even though it was installed new and never opened. It happened after I had travelled with the bike in the car with the wheels off. It probably released when the chain was slack and never fully locked again. Now I check it whenever I remove the wheel to be sure it’s fully engaged.
I stopped using the Sram links because they wear faster than my Campy chains.
I’ve never liked Power-links all that much. I never found them all that easy to open, and I always wound up with filthy hands. However, using a chain tool takes very little skill. And even if one removes a chain multiple times, the likelihood of opening it at the same link is very low.
I usually ride fixed gear and have several bikes with different gearing. I never use a Power-Link on a fixed gear bike out of a surfeit of precaution because a chain that suddenly loosens up on a fixie can lead to its popping off the chainring and then wrapping around the crank and locking up the rear wheel, which usually results in a crash.
I did notice on the Connex website, that they sell half-links, which are one of the best inventions ever for single-speed or fixed gear bikes converted from geared bikes. Frames from the 1970’s and earlier had fairly long horizontal dropouts. Those of the 1980’s had considerably shorter dropouts. A half-link substantially increases gear choices on these 1980’s frames. Since one tooth moves the rear axle 1/8″ and a full link moves it 1/2″, a half link finds the sweet spot by moving it 1/4″. For those riding single speed or fixed gear who would like to make a minor change in gearing, a half-link is often the perfect solution.
I’m confused, why is that some 40 years ago when I use to hot wax my chains I could disconnect chains to clean and hot wax them repeatedly with no issues of the chain breaking even after many times of taking the chain apart, so what’s changed over the years?
Also today I never take a chain off to clean it, I simply clean it with a damp sponge and non citrus Dawn for Dishes, then rinse with a gentle spray of water.
Back in the day, chain plates were thicker and the pins were friction fit. You could push them out and push them back in with little to worry about. Perhaps if you pushed the same pin in and out repeatedly you might find a problem, but that was an unlikely scenario.
Advance a few decades and chain plates are much thinner and the pin ends are peened to hold them in place. When you push one of them out, it takes a lot more force on the chain tool and it removes the peened end of the pin. On Campy chains, it takes so much force to remove a pin that you often see a spark when the pin breaks loose. Now that pin can much more easily come out of the thinner plate without that peened end.
I had my sram power link fail .I. Didn’t know it was a one time use .
I use the KMC Missing Links on my 11 Speed Chains. I like to completely remove them and throughly clean at roughly 750 mile intervals in normal (mostly dry) road riding conditions. You get a large amount of grit and dirt off when rinsing the chain off after degreasing a completely slack chain. Given the minimal cost of these Missing Links (and the controversy), I just use a new one when I reinstall the chain. Why tale the risk that it fails 40 miles from your car or home? Plus, I feel like I extend the life of the chain this way which can save you a few bucks to offset the cost of the links. KSS….
Ok here’s my two cents I’ve been riding since the mid 70’s. Started using the “missing link” in the 80’s? In all the years it has come apart ONCE and that was when I was using paraffin and there was too much wax on the chain so when free wheeling it came apart with a 9-speed drive train. Fast forward to my current situation and the last 15years of cleaning. With my current 11 speed eTap drive train I pull apart the chain about every 1000-1500 miles it goes into a ultrasonic cleaner filled with mineral spirits (then the cassette) front chain rings and derailleur pulleys are wiped down/cleaned with degreaser. All is re-lubed and ready for riding. The chain is always wiped down after each ride with the chain stretch measured every couple of weeks. I measure it in several different places with the Park Chain Checker CC-3.2 at 50% for me it’s done. Once or twice when I measured the chain including the SRAM Power Link it was at 50% I replace the link only and not the chain. I normally get 2500-3500 miles on my chains. Here in western NC I average 8500 miles a year and about 450,000′ of climbing so as you can image I do plenty of shifting. My only caveat is to make sure you keep an eye on the replaceable link you use while measuring the chain to include the link. I know this goes against the info stated above but I feel comfortable with what I do. P.S. I do carry a spare link and for those who don’t care about drive train maintenance as much as I do I would recommend to just replace the link each time you pull apart the chain.
Problem solved master link.was disconnecting.after a few uses I put a dab of grease on.pins before reassembling. and. Inever happens but.master link.must wear out eventually. I think chain crack after shifting gear means there’s too much play there but that’s aftern12 or more uses