# Inexpensive Derailleur Hanger Adjustment Tool?



## DavidR1 (Jul 7, 2008)

I bent my rear derailleur hanger and would like to repair it myself instead of taking it to a shop. Is there an alternative to the $60 DAG-2? It looks like a pretty simple tool, has anybody made one?


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## Birdman (Dec 31, 2003)

*Crescent wrench?*

I've straightened them using a large crescent wrench snugged up onto the faces of the hanger and "eyeballing" it.

The DAG does work pretty good, though. Maybe a local shop will lend you one?

JMJ


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## 3034 (Apr 12, 2006)

I've had my derailuer be out 1" as measured at the rim using a DAG-2
this is after 'eyeballing' and thinking its perfect.
The DAG is a must if you ride rough stuff


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## MikeyLikesIt (Dec 9, 2007)

Dag is good...bought one this summer and it has already paid for itself. I could eyeball it and get it so it shifted OK but couldn't get it close enough to eliminate all the chainline noise. I have also straightened the non-removable hanger on my titanium road bike with it...no telling how much money that saved me. 

I'm sure you could rig something that would work but there is more to the DAG than meets the eye. You could use the cresent wrench for bending and maybe make a gage out of PVC or wood etc. Simpler just to buy the DAG and it is one tool that will pay for itself quickly if you ride the ruff stuff. 

If you buy a new hanger from your LBS, maybe they'll straighten your old one to keep as a trail spare. Just a thought.
M


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## neex (Mar 30, 2005)

Try this... Thread an axle (use a full wheel with the QR pulled out) into the derailleur... Make slight adjustments to retune the hanger till the two wheels are completely parallel. You can also use a 10mm/12mm (not 100% sure which) allen key but the wheel trick is the best I've seen. If you have an oversized axle then you're outta luck. Good luck. A.


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## highdelll (Oct 3, 2008)

neex said:


> Try this... Thread an axle (use a full wheel with the QR pulled out) into the derailleur... Make slight adjustments to retune the hanger till the two wheels are completely parallel. You can also use a 10mm/12mm (not 100% sure which) allen key but the wheel trick is the best I've seen. If you have an oversized axle then you're outta luck. Good luck. A.


clever


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## neex (Mar 30, 2005)

highdelll said:


> clever


I can't take credit for that tip as I learned it somewhere. I can't recall where but it has always ranked high as a good tip for sure. It really works!

Thanks,
Andrew.


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## Dremer03 (Jun 19, 2009)

I actually had to adjust mine the other day, we used a crescent wrench and some patients. I was riding, and then I tried to shift into my biggest rear cog and I threw my chain into my spokes. I was 1 full gear off, I cound't get into my smallest cog which was fine but it is kind of annoying having to think about what gear you are in so you dont over shift.


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## bvibert (Mar 30, 2006)

Tweaking a hanger with pliers, or whatever, is easy, getting it lined up perfectly in all directions by eye is the tricky part. That's where having the tool would come in handy.

I like the wheel idea, sounds like it would work pretty well.


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## jeffscott (May 10, 2006)

DavidR1 said:


> I bent my rear derailleur hanger and would like to repair it myself instead of taking it to a shop. Is there an alternative to the $60 DAG-2? It looks like a pretty simple tool, has anybody made one?


Nope, but here is what I did with good sucess.

Hand bend the thing straight for a field fix, just close enough to get home...

Remove Der Hanger from bike...

Place Der Hanger on my nice flat spot on my vice...(I did trim the flat spot up with a file).

Gently tap straight with a small ball peen hamer (flat end).

measure with a known straight edge, mechanics square....

When perfect reinstall....

I get perfect shifts and no chain noise just like before.


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## dcp_nz (Apr 16, 2009)

Well I just used my new DAG-2 the other day and report from my wife is that shifting was perfect.

I'd previously tried to align the visibly out of alignment hanger with the plier/wrench method and eyeballing based on chain alignment as it ran through the derailleur. Had got it shifting OK but not great. Using the DAG showed it was still at least an inch out of alignment at the rim. Found I had to bend the thing pretty hard so appreciated the construction of the DAG.

Definitely a tool I didn't know I needed but now would not be without.


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## GEARHEAD_ENG (Jul 22, 2009)

jeffscott said:


> Nope, but here is what I did with good sucess.
> 
> Hand bend the thing straight for a field fix, just close enough to get home...
> 
> ...


I used the same method, but with a granite surface plate and a dead blow hammer. I was able to get it within .003 surface flatness.


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## ettore (Nov 13, 2004)

GEARHEAD_ENG said:


> I used the same method, but with a granite surface plate and a dead blow hammer. I was able to get it within .003 surface flatness.


Insane, the surface of my hangers on every bike I have ever owned have WAY more than 0.003" divets in it bone stock ... I guess not all hangers are made of that porous aluminum my bikes have.


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## GEARHEAD_ENG (Jul 22, 2009)

Yeah mine was made out of really smooth forged aluminum. Set it on the surface plate and then set a dial indicator on top and did a quick sweep. Probably didn't need to be that accurate but I have the tools.


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## thefuzzbl (Jul 5, 2006)

making it perfectly straight only works well if the frame is perfect, which is rarely the case. the dag-2 is the best solution.


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## fluffypanda (Jul 6, 2009)

neex said:


> Try this... Thread an axle (use a full wheel with the QR pulled out) into the derailleur... Make slight adjustments to retune the hanger till the two wheels are completely parallel. You can also use a 10mm/12mm (not 100% sure which) allen key but the wheel trick is the best I've seen. If you have an oversized axle then you're outta luck. Good luck. A.


this worked like a charm! saved me a trip to the bike shop. thanks!


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## emeterio (Jul 11, 2007)

may you upload some pics?


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## PauLCa916 (Jul 1, 2013)

I recently bought a Park Tool DAG-2 when I was setting up my new SRAM XX 1 drive train.
Even thou my shifting was perfect with the original 2 x 10 set up.
When I checked with the DAG-2 it was off about 3/4".
I highly recommend the DAG-2 watch for sales I got mine for under $60 and it was money well spent.


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## Birdman (Dec 31, 2003)

thefuzzbl said:


> making it perfectly straight only works well if the frame is perfect, which is rarely the case. the dag-2 is the best solution.


Agree - just flattening the hanger does not account for any misalignment in the dropout/hanger mount itself.

JMJ


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## noapathy (Jun 24, 2008)

Dremer03 said:


> I actually had to adjust mine the other day, we used a crescent wrench and some patients. I was riding, and then I tried to shift into my biggest rear cog and I threw my chain into my spokes. I was 1 full gear off, I cound't get into my smallest cog which was fine but it is kind of annoying having to think about what gear you are in so you dont over shift.


This sounds less like an alignment issue and more like poor adjustment. Adjust the rear derailleur and that should cure what you describe (barrel adjuster for a MTB is on the bar, but otherwise the same).

*edit: if you have a SRAM derailleur B screw is different (not as close as Shimano)


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## Bigmatt125 (Aug 24, 2015)

The DAG-2 is great and well worth the ~60 bucks. I use mine liberally. It's amazing how often I find out a hanger is misaligned even when it looks OK or when there's no trauma related complaint. It's especially good on bikes that get transported a lot and for those non-descriptive "It just doesn't shift right" complaints. Slight adjustments make huge differences. Granted, I don't charge for my time anymore, but the frequency of misaligned hangers seems so great that I rarely find a good reason not the throw it on. I even keep it at close hand at races and for sag support work. 

The only other tool I've tried was an old Shimano Dura-Ace tool, which had a graduated rule, but seemed kinda flimsy. The current Shimano tool looks better, but why not just buy the factory that makes them if you have that kind of cash? ut: I have not experienced a DAG-2 with too much play. I think the DAG-2 is tough to beat.


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## JonathanGennick (Sep 15, 2006)

Bigmatt125 said:


> but the frequency of misaligned hangers seems so great that I rarely find a good reason not the throw it on.


Some here. It's often the first thing I reach for in response to complaints about shifting. Bikes get banged around in garages. Kids drop them on lawns. In the non-enthusiast world bikes get banged around a lot and people don't really realize how just a little bump can knock their alignment out of whack and gum up their shifting.


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## Bigmatt125 (Aug 24, 2015)

DavidR1 said:


> It looks like a pretty simple tool, has anybody made one?


To answer to OP's original question, I did make one once in a pinch. It was a complete waste of time. The additional time I would have spent to get it right would have overshadowed the cost for a Park. The idea of using a wheel with a threaded axle to thread into the hanger sounds like a better impromptu solution than making one, but if you buy one I bet you'll us it all the time.


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## customfab (Jun 8, 2008)

With modern drive trains accuracy is everything. With floating top pulleys going away and more and more gears getting placed onto the freehub the tolerance for alignment is a lot smaller than it use to be. I shoot for +/-2mm measure at the rim and it makes a difference.


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## Flamingtaco (Mar 12, 2012)

Dremer03 said:


> I actually had to adjust mine the other day, we used a crescent wrench and some patients. I was riding, and then I tried to shift into my biggest rear cog and I threw my chain into my spokes. I was 1 full gear off, I cound't get into my smallest cog which was fine but it is kind of annoying having to think about what gear you are in so you dont over shift.


Always adjust the set screws anytime you tweak the hanger. Quick way to end up replacing drive side spokes.

LBS tweaks my hangers, no charge. Takes them about two minutes.


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## poimein (Jun 2, 2015)

DavidR1 said:


> I bent my rear derailleur hanger and would like to repair it myself instead of taking it to a shop. Is there an alternative to the $60 DAG-2? It looks like a pretty simple tool, has anybody made one?


Try these: X-Tools Pro Gear Hanger Alignment Tool (around $53 new at Chain Reaction Cycles) or the IceToolz Xpert Derailleur Alignment tool (around $56 new on eBay)


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## mgreene888 (Oct 21, 2013)

Has nobody seen this video? 




I made these and they work great - $0 cost if you already have threaded rod but it is cheep at Home Depot.

Mike


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## santacruzr (Aug 11, 2015)

I'm a big fan of "the right tool for the job". I have used a DAG for years and it is indispensable for making shifting right. With that said, I cannot recommend Abbey tools HAG even more. It addresses the short comings of the DAG's indicator movement around the stays and will let you gauge the entire wheel to the hanger. 

To me it is worth every penny and I haven't touched the Park unit since I bought it.


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## poimein (Jun 2, 2015)

Will that idea with the 8 mm threaded rods, washers, and bolts work with a through axle? I would think it would work only with standard, quick-release axles.


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## mgreene888 (Oct 21, 2013)

I dont see why not. The bolt that goes through the dropouts is only used as a straight reference for the derailleur bolt. I would assume that you would hold it in with nuts and washers - just like on a bike with dropouts. The cool thing about this system is that it is so intuitive - you can easily see if the hanger is not parallel with the axle. And theres no need for a tool to bend the hanger - they are soft and the rod gives plenty of leverage to make reasonable tweaks.

If you try it - make sure the rods you buy are straight. To check, just roll them on the concrete at the store. 

Mike


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## poimein (Jun 2, 2015)

Thanks.


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