Jim’s Tech Talk
By Jim Langley
Game-changing derailleur hanger alignment
Easy to use – sight across rods then adjust hanger until rods are parallel
More accurate alignment
Small and light to take along as a ride-saver
Price: Quick Release Kit: $59.95; Thru Axle Kit: $99.95; Quick Release and Thru Axle Kit: $119.95
Weight: Quick Release Kit: 175 grams; Thru Axle Kit: 297 grams; Quick Release and Thru Axle Kit: 324 grams
Materials: 7075-T6/6061-T6 aluminum and 303 stainless steel
Made in the USA
Frames with standard M10x1 threaded derailleur hangers
Frames with 12mm thru axles or 5mm quick releases
Frame spacing: Quick release: all widths; Thru axle: 12×142 to 12×197
How obtained: Company sample
RBR advertiser: No
A Brilliant New Tool for Aligning Bent Derailleur Hangers
I think this new derailleur hanger aligner from Wolf Tooth is one of the most impressive cycling inventions to come along in years. It’s a completely new take on a tool that’s been around – essentially in the same form, for at least 60 years, maybe even longer.
And here’s the thing, that old tool became the only tool available for the job. Lots of companies have made improvements over the decades (since 1971, I’ve owned five of them). Yet no matter which one you used – it was always a difficult tool to operate and it didn’t align hangers very accurately as a result. In the photo the two tools on top are of the old design and Wolf Tooth’s is at the bottom.
That’s why it’s so exciting to see Wolf Tooth’s ingenious solution. Unlike the old standard tools, theirs is easier to use, makes more accurate adjustments, is only $59.95 for the quick release kit ($99.95 or thru-axle), and is even small enough to fit in a pack and take along on rides. I like it so much I’m giving it 5 stars, our highest rating.
A better mousetrap for derailleur hanger straightening and alignment couldn’t have come along at a more appropriate time. Now that our bikes have tightly spaced 10-, 11-,and 12-speed drivetrains, it’s essential for rear derailleurs to be properly aligned to the rear cassette for crisp, consistent shifting. Perfect alignment is even more important with electronic drivetrains that rely on exact steps of a motor for each shift (versus cables that develop play).
Yet, just when it’s so important to have perfect hanger alignment, the majority of bicycles today come with easily bent aluminum derailleur hangers. Something as seemingly harmless as your bike falling over can result in the rear derailleur hitting the ground (or if the bike itself falls over, such as when it’s precariously parked). Crashing and hitting the derailleur will bend the hanger worse, as can getting something stuck in the derailleur.
What’s more, lots of roadies are discovering the dirt, and long gravel rides. Meanwhile, touring, randonneuring and bike camping are becoming popular again. These types of riding increase the chances of bike-dropping, crashing and bending a derailleur hanger. So Wolf Tooth making a pro tool that actually works and gets small enough to carry is genius (all the pieces fit inside the handle).
Is a bent derailleur hanger that big a deal?
Whether or not you should worry about a bent hanger depends on how badly bent it is. Sometimes it’s bent even on a new bike, and you may not notice the occasional shifting hiccup or a bit more noise than there should be. But ideally, your bike wouldn’t have these issues and straightening the hanger would fix them.
With worse bends, you also might not realize anything’s wrong. But in that case, the hanger is badly bent and now angled in too close to the rear wheel. This usually causes shifting into the spokes. If you’ll pardon the pun, that can create a chain reaction, the rear derailleur diving into the spokes, getting mangled by them and probably tearing some of them out. Obviously you want to avoid this.
Hangers are supposed to bend
The ironic thing is that because the derailleur is so much longer than the hanger and can exert so much leverage on it, hangers are actually designed to bend so that they don’t break. That design originated with steel frames on which a broken hanger might require a difficult and costly repair (replacing the entire dropout plus repainting).
Today’s mostly aluminum hangers are almost always replaceable, but you still don’t want to risk breaking them. Because it might ruin the attachment point, which could wreck the frame.
All these reasons are why I think a lot of roadies would like to own a hanger alignment tool, and especially one as revolutionary and easy to use as Wolf Tooth’s.
Using Wolf Tooth’s Aligner
Because this new tool checks alignment by referencing the rear axle (instead of the rear rim like all previous designs), Wolf Tooth has two kits. One is for bikes with quick-release axles, and one is for thru-axle bikes (you can purchase a combined kit and you can upgrade a thru-axle kit to add the quick-release option, too).
Whichever axle type you have, when the Wolf Tooth kit is in place on the bike, it gives you two protruding rods. One extends from the rear axle and is fixed in position for reference. The other rod extends from the hole in the derailleur hanger (you remove the derailleur first).
Once the two rods are in place, you’re ready to both check the alignment and fix any issues. To check, you simply sight from all angles and ensure that the two rods are always parallel to each other. If so, you’re good to go – nothing to straighten or fix.
If the hanger is bent like the one in the photo, it’s easy to see. And to align the hanger just takes gently pressing on the hanger rod until it is parallel to the fixed axle rod. You sight from every direction and keep fine tuning until you see parallel lines looking across both rods.
This is much easier than the way it’s done with all the “old” conventional hanger alignment tools, which use multiple reference points on the rim. And, comparing my results with both tools, Wolf Tooth’s better mousetrap gets more accurate results. That’s the most important part and why I’m err.. howling with excitement over Wolf Tooth’s terrific new tool.
Comparison of Wolf Tooth’s and a convention hanger alignment tool
In this video, I show how both tools work to demonstrate why I think this new design is such a game-changer.
For step-by-step video instructions on tool setup and use, watch Wolf Tooth’s videos:
Quick Release: https://www.youtube.com/watch?v=IpWoySCg0BA
Ride total: 9,310
Jim Langley is RBR’s Technical Editor. He has been a pro mechanic and cycling writer for more than 40 years. He’s the author of Your Home Bicycle Workshop in the RBR eBookstore. Check out his “cycling aficionado” website at http://www.jimlangley.net, his Q&A blog and updates at Twitter. Jim’s streak of consecutive cycling days has reached more than 8,000. Click to read Jim’s full bio.