Bicycle Mechanics - Trying to find a workable derailer hanger for an old MTB

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TheatreME
12-23-08, 07:52 AM
Hello, all.

I am turning and old Iron Horse AT-50 MTB into a touring rig. I have already upgraded the drive train and added drops and barends. Everything is falling into place. However I do not have the right derailer hanger. The drop outs are horizontal and with a single set of braze ons, but nowhere to attach the hangar securely to the bike. It's the rear hangar off an old road bike and it has a in effect a horizontal dropout itself. Right now I am simply lining everything up and using the nutted axle on my rear wheel to keep everything tight. This setup works but makes fixing flats etc is a bigger pain than usual as the rear derailer/ hangar assembly falls off as soon as the wheel is removed. Any help would be appreciated. I checked http://www.derailleurhanger.com/ after looking through some old threads, but no luck.

Sorry for the long post,

thanks


Little Darwin
12-23-08, 08:00 AM
Do you have a bike that was not built with an integrated hanger? If so, you may need an adapter claw like this:

http://www.loosescrews.com/index.cgi?d=single&c=Derailleur&sc=Rear%20Hanger&tc=&item_id=LS-1701PD&id=55373818028

It basically attaches your derailleur into a horizontal dropout and would allow you to remove your wheel while leaving the RD in place.

TheatreME
12-23-08, 08:03 AM
That's exactly what I need. Thanks so much.


Little Darwin
12-23-08, 09:30 AM
One minor caution, this basically turns your RD into a "cheap" rear derailleur like what is used with bolt on rear wheels, and I am not sure how well it might work with a quick release, as the effective thickness of the right side drop out is about twice as thick as normal.

I have used them successfully on a couple of bikes with bolt on rear wheels. QR should work, just use caution until you are sure of it.

Also, they are available from other sources than Loose Screws, that is just one of my favorite online sources for small parts.

LarDasse74
12-23-08, 11:05 AM
One minor caution, this basically turns your RD into a "cheap" rear derailleur like what is used with bolt on rear wheels, and I am not sure how well it might work with a quick release, as the effective thickness of the right side drop out is about twice as thick as normal.

I have used them successfully on a couple of bikes with bolt on rear wheels. QR should work, just use caution until you are sure of it.

Also, they are available from other sources than Loose Screws, that is just one of my favorite online sources for small parts.

The derailleur claw is really the only simple option - that is what the frame was designed to use.

A quick release will generally work fine with the claw... it is the other side you need to be concerned about - the thin dropout may not be squeezed between the QR and the axle locknut. The axle stub on the non-drive-side may have to be cut slightly shorter.

The clw does not make a good deraiileur into a poor derailleur - the onjly thing that cheap derailleurs and good derailleurs w/claw have in common is the fact that the hanger for both is held under the axle. A good derailleur will still be more precise and last longer.

As long as you make sure to use the screw and little half-moon washer with the claw it is a very solid attachment.

cascade168
12-23-08, 02:05 PM
On many early '80's Japanese bikes those type hangers were the standard. I have an old Nishiki with one of those that has a modern 105 RD mounted on it. Works fine with no problems. Plus, very cheap to replace.

Also, there is no problem using a QR with one of these, as long as your axle is not too long.

Little Darwin
12-23-08, 02:13 PM
The clw does not make a good deraiileur into a poor derailleur

Good point, In rereading my message it did seem to say that, but it is not what I meant. I just meant that it replicated the way cheap derailleurs used to be attached. ;)

I have attached some very nice RDs this way and as mentioned they still functioned very well.