Dérailleur hanger tools

This is one of those bit I miss from the Cycling Tips gang, are the good articles and chat about tools to keep us rolling smoothly (or maybe just slightly smoother).

My summer bike has spent the winter on the turbo in a couple of years so have put off sorting gears. I’ve tried eye balling the hanger but it’s not straight still.

For a tool I might use a couple times a year I don’t want to spend Park Tools money but equally the really cheap ZTTO (and clones) are too cheap to be accurate according to reviews.

eBay has a Park Tools clone for £30ish and Lifeline do one for £40. Want tools do the well stocked TR mechanics use?

I work at a shop and we do it for $15. For as seldom as they’re needed (I think I’ve straightened hangers twice in 15+ years of riding) it’s probably not necessary to have your own, in my opinion.


For modern bikes, these just aren’t needed. For an old steel bike, sure. For a modern AL or CF bike, you’re going to break something. Modern hangers are a thick hunk of metal attached by two little screws and the axle usually. The axle attachment almost guarantees the hanger is aligned with the cassette. If you’ve somehow bent the hanger, you’re better off getting a new hanger anyway.

It’s always the rear derailleur cage. If it’s not that, check the hub width. If it’s not that replace the hanger.

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Think I’ll get my friendly lbs to check and tune the gears then.

Only reason I think it’s the hanger is I’ve not crashed this mech, the hub/cassette was known working and can only get ~50% of the gears to run smoothly.

Thanks for opinions everyone!

I have an off-brand derailleur hanger gauge & it works ok. My bikes get transported in the back of an auto when I race & the hanger can get bumped…so that tool gets used fairly regularly.

But if it’s something you just gotta use every so often…well, you don’t have to throw money at your local bike mechanic but also it doesn’t hurt to give him some business every now and then, either. As others in this thread have pointed out.

Here is the tool I use:

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I made my own hanger tool using an old wheel axle and steel tube. The hanger thread matches the axle, and the crucial task is to drill the tube at 90 degrees. At the rim end I use an old spoke inserted into a plastic cork as the guide. I use it fairly often as my CX bikes get some abuse if I crash in a race.

This is not true, hangers bend pretty easy, thats their whole purpose. Ive had to straighten my hanger multiple time over the years on my thru axle CF bike. Hangers bend and you can easily bend them back, no need to buy a new hanger.


Or maybe that’s what Big Derailleur Hanger wants you to believe!

On most bikes, the hanger is waaaayyy stronger than the RD b-bolt or the pulley arm. This is a modern road disc (Spec Roubaix) hanger

It’s way too short and thick to realistically bend before the hollow aluminum b-bolt gets ripped out of it. Also, the materials it’s attached to aren’t strong enough to give it any leverage.

Here’s a QR one (2016 Giant TCR). This will totally rip itself out of of the frame or destroy the QR before it bends.

If you’re bending this, you’re realistically just deforming the mating surface temporary. Most carbon and AL bikes solid AL dropouts. That probably aren’t going to bend all that much.

here’s a mid-90s steel frame. Here, you’re probably not bending the hanger either, but the joint of the welds and the dropout tab.

If you’re bending this, you’re realistically just deforming the mating surface temporary. Most carbon and AL bikes solid AL dropouts. That probably aren’t going to bend all that much.

I have one of these, although I admittedly have a tool fetish:

And I absolutely have found them out of spec and needing to be tweaked back on “modern” bikes.

Going to be checking my XC bike soon as the shifting is a little out of whack so need to go through the whole setup anyways, and this part only takes a minute or two.


You adjust the hanger with the wheel bolted in, you are using the rim as a reference when using the tool. You are not putting load on the welds of the whole drop out when making the adjustment on that steel bike or any other bike.

I adjusted 100s back when I was a bike mechanic, when steel bikes were still the most common thing through the shop, and own the park tool myself now. IF we replaced a hanger on an aluminum bike they all needed adjustment. My tool is currently being lent to a friend who was chasing a problem on his daughters bike for a year after it arrived (bikes direct I think), hanger was bent out of the box. For some reason despite my Tri bike spending most of its life on the trainer, I find I need to make an adjustment to the hanger before my first race each season.

It doesn’t take much at all for it to cause it to be out of alignment and cause issues.

This is not a big hanger conspiracy, it is a thing, do I think everyone should go buy a tool? no… but I bet most people here could use an adjustment.

For those curious here is the process for adjusting. How to Align a Derailleur Hanger Using the DAG-2.2 - YouTube


Will most modern drivetrains (especially electronic) shift OK without a perfectly aligned hanger? Yep.

Does having a well aligned hanger improve shift performance and often fix issues that many home mechanics struggle with? Absolutely.

There are a couple guys on my team (including me) that have DAG 2.2’s and they get passed around a bit and have solved many shifting challenges. It’s one of my favorite tools in the box.

In my experience, even brand new bikes often don’t have well aligned RD hangers (bad shops don’t check them before delivery, just run through the gears on the stand). I’m not sure what folks are talking about with carbon frames not having much adjustment here (If I’m reading this right), that’s not my experience. And the short sram universal hanger can certainly be adjusted. With the tight tolerances of 12 speed drivetrains, a small misalignment can affect shifting. Hanger alignment and B gap adjustment are the 2 things I see home mechanics often ignoring, they should both be part of any regular tune up in my opinion and have a significant affect on shifting.

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My modern Eagle AXS 12spd equipped 3T disagrees with this. I adjust the hanger on that bike more than any other

A hanger tool isn’t a necessity per se but it usually can be the difference between good shifting and perfect shifting.

QR axle thread is the same as rear mech bolt thread… so if you have a QR wheel, unscrew the mech, screw the second wheel onto the hanger, use second wheel as a lever to make the two wheels aligned. Job done, no money spent :+1:

Yeah… because you’re not adjusting the derailleur hanger. You’re bending something else or you’re just bending it into the paint for a minute.

Not sure what you’re getting at here.

I’m well aware that the 3T hanger system is different than most (and it sucks) but I’m fairly certain I know better than you what I’m adjusting. Ha. If the axle is tightened in the hanger threads properly then using a hanger tool, like on every other bike, should only be adjusting the hanger. The “paint” has no affect here. Not to mention there’s no paint there anyway.

I just find that on this 12spd AXS I adjust the hanger more than my 12 and 11spd Shimano bikes.

YMMV but that’s my experience. :man_shrugging: