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.
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.
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.
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.
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.
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
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.
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