No matter how carefully you maintain your bike’s chain, you will, eventually, have to replace it. After testing eight of the most promising examples, we think the Park Tool CT-5 Mini Chain Brute Chain Tool is the best for most people. It works with anything from an 8-speed chain to the newest 11-speed chains, and it’s surprisingly comfortable to hold, given its small size.
Yes, you could have a bike shop replace the chain, but if you want to do it yourself the Park Tool CT-5 Mini Chain Brute Chain Tool can do it for the cost of that labor. Many of the smaller chain tools available have difficult-to-hold, uncomfortable cranks, but the Mini’s are surprisingly workable for its size. This matters because you have to turn the handle hard at times to force the pin through the chain, no matter which tool you use. Also, that small size makes it easier to maneuver if you’re working on a chain from the back—some mechanics believe that inserting the pin to relink the chain from the side facing away from you makes it stronger.
In addition, it’s also incredibly versatile. There are a lot of bike parts, in a lot of different sizes, and chains are no exception. The Mini Brute will work on chain sizes from 8-speed up to 11-speed, which covers just about everything you may encounter. It won’t work on Campagnolo parts (“Campy,” for short; it’s an Italian manufacturer of bicycle components), but that isn’t unusual.
If your bike has Campy components, your ears will have pricked up—Pedro’s Pro Chain Tool uses a patented “retracting pin guide” borrowed from its top-of-the-line (and very expensive!) Tutto Multi-Chain Tool, and works on all sizes of chain, including Campy chains. However, its list price is more than four times that of the Mini Brute. If you’re planning to make a habit out of working on friends’ and neighbors’ bikes, the Pedro’s Pro might make sense for you, otherwise, it’s overkill.
After five years of commuting daily to my desk job by bike, I now split my time between writing at my home in San Francisco and working at my local bike shop, pitching in with minor repairs when the real mechanics are swamped. With six bikes in my garage, I also have plenty of opportunities to put into practice what they’ve been teaching me.
A chain tool “breaks” a chain by screwing a pin into the rivet joining two links, forcing it out and thus separating the links. To connect two links, you use the tool to drive a new rivet—confusingly called a connector pin—into the empty rivet holes.
After researching all the chain tools available in the US, checking in with the experts we’d contacted for our recent bike-repair-kit guide, and digging up as many reviews as we could find (bike tools are a sorely underrepresented category) we put the eight best options to work. We spent about six hours breaking and reconnecting chains of many different widths, from single-speed to 11-speed, over and over again.
Even the shop-quality tools we tested had some problems. For instance, although the Park Tool CT-4.3 Master Chain Tool With Peening Anvil is aimed at pro mechanics—and does, therefore, have comfy, rubber-cushioned handles—it wasn’t able to cope with the single-speed chains I tried it on, despite the fact that it’s supposedly compatible with them. Instead of driving its pin into the rivet I wanted to remove, the tool twisted the link itself beyond repair time and time again.
Other pro-level tools that we did like, such as the Birzman Damselfly Universal, were just too big an investment for a tool that most people aren’t going to use day in and day out. Although, if you are going to be—and you don’t have any Campy-philiac friends, relations, or customers—you might want to look into this one. The Damselfly Universal has a wide, wing-shaped crank that is easy to grip and doesn’t feel like it will fall apart in your hand. Also, an internal spring pushes the chain guide up against the chain, meaning you can use it with anything from the newest, thinnest 11-speed chains to older, thicker 8-speed chains and even single-speed chains, which are heavier still. Not having a stationary chain guide, though, has a downside: You can’t use the guide to straighten out a kinked chain. And unlike the Pedro’s Pro Tool and the Park Tool CT-4.3, this tool won’t work with Campy chains.
The other category of tool, outside of the shop-quality options, are typically dual-purpose products, meant to be stuck in a pocket and used on the trail as well as at home. Our pick, the Park Tool CT-5, falls into this category, as do the more expensive Pedro’s Six-Pack Chain Tool and Lezyne Chain Drive, which did both perform as they should. This couldn’t be said of the Super B TB-CC50 Rivet Extractor, which not only isn’t comfortable to hold or easy to use, but whose chain guide broke off when we tried to drive a Shimano connector pin into a chain link.
Please don't overwater the ficus.