Derailleur Hanger Thread Repair

If the mounting threads of your derailleur hanger become damaged, it can be difficult or impossible to install the derailleur. If hanger replacement isn't an option, then it is time to repair the threads. This video will walk you through a variety of derailleur hanger thread repair methods including: Tapping Damaged Threads, using a Coil Repair Kit, and T-Nut Systems.

Questions or comments? Leave them below!

Video Contents:
00:00 Video Start
00:50 Tapping Damaged Threads
03:08 Coil Repair Kits
05:32 T-Nut Systems

➤ Tools & materials used:

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[pattskatoey]

Calvin is the man! What a coincidence this video is up when I have this issue.I will have to purchase a coil kit.

[nemeczek]

I bought a new set of allen keys and used them for the first time to install a deraileur. After applying way too much force I damaged the thread. I bought a helicoil set to fix it but have not used it yet. This video will motivate me to do the job. Thank you. Never use too much force to install your deraileur, kids.

[neutralscreenname]

The tap from the opposite side method worked! Threads were pretty cross-threaded, except the last couple looked good still. So the derailleur would screw on pretty easy (albeit slightly crooked), but then stop suddenly when it hit the good threads. Just got an M10-1 tap + cutting fluid at the hardware store, followed the video, and now it’s on straight and tight.

[bmxscape]

thankfully i havn't had to do this yet but i know my future holds this job somewhere so thank you for showing some solutions. Never seen a t-nut that wasn't meant for woodworking, seems like a perfect solution

[paisfr]

Bonjour Calvin , c'est un travail très délicat 😊 Thank you

[larryt.atcycleitalia]

Back-in-the-day I "barnyarded" a Klein (aluminum) hanger that was bent AND split with a T-nut quick-epoxied into a hole prepared with a reamer. Ugly-as-sin, but the tour company client rode his bike for years afterward with zero issues!

[dorian]

Thanks for help i have an old german city bike (>2000) from alu 7071 and ear thread is damaged and is on same piece with frame . Is very handy bike for city comparing with a mtb narow frame and front fork perfect for tide places . Now i will be able to repair it . Thanks so much .

[dawbool]

Thank you! I guess that in some cases a rear derailleur re-alignment might be advisable...

[type]

If you aren't lucky enough to have a nice M10 x 1mm tap, you can use an angle-grinder to cut some sharp-edged grooves into a spare quick-release M10 axle (which are usually cro-moly, or some other hard metal), and use it as a tap for the hanger. Not a recommended method, but might get help someone out in an emergency.

[Hidenberg]

There is solution of my every problem on this channel

[johngoldenbritt]

No more chain crossing for me after Record Short Cage/Hanger destruction in 53/30. Forgot to look down and confirm gearing before 😩😩😩. We had to file my T nut down on inside to work with 10 speed 13 cog so that chain would not rub it. Klein Quantum Race was 9 speed originally, so space is tight!. Coil might have been better? Great Video!!

[dandel]

Hace un par de años hice las mismas reparaciones con el mismo orden. Primero el inserto roscado. No me gusto la terminación. Luego opté por la tuerca embutida. Funcionó correctamente hasta qué se terminó de quebrar el fusible. En el agujero agrandado. Al ser la pieza fija al cuadro (aluminio) terminé optando por cortar, amoldar un fusible postizo de diseño sencillo.

[adriankelly_edinburgh]

Great video as usual, Calvin. Can you use a similar approach to repair damaged crank arm threads?

[mm-levo]

Buen vídeo, pero no saldría mas barato comprar una puntera nueva?😅

[AdamOmidpanah]

I would only say that metal splinters are the f@#$ing worst and a pair of shop gloves goes a long way in a tap job. Of course, Calvin is the GOAT and has no need for such precautions.

[siedliko]

I don't know about heli coil.
That will add 2 grams to the bike, it will slow me down by 0.001mph. So I will pass on that fix and get a new $5000 bike.

[bobissik]

The Tee Nut (or "Sleeve Nut") seems like a good idea; anyone knows where to get them (in Canada, preferably) ?

[SamPrince]

My problem is I can't unscrew the derailleur from the(snapped) hanger at all, even after attaching a long spanner to my allen key for more torque. Possibly the threads are mangled but Ive no idea how to get the pieces apart

[SatyaSanaatan]

How can i repair the threads of the rear derailleur barrel adjuster ( the tube of adjuster seems fine but the part of derailleur where the barrel adjuster tube goes is missing first 2 threads

[cfieber]

More often the hanger is bend or broken. I never had to do something like this but now it is written. 🙄 Yeah I really want to spend more time to retap and helicoil it than it is worth. More often I do this on cranks 😅