Bicycle Mechanics - Worn out integrated hanger - options?

I have an aluminum frame that has had the rear derailleur/dropout area bent and straightened one too many times. Now the hanger will bend if I stare at it long enough. (I'm working my way up to bending spoons with my telekinetic abilities....)

The hanger is part of the frame - it is not a separate piece. What options - if any - do I have to make this area more secure again? Right now, this area has the consistency of Jello, and one more re-straightening will cause this piece to fall right off.

Hold on a second... you were rebending AL?

sounds like time for a new frame.

Hold on a second... you were rebending AL?


Ummmm....yeah....maybe....

I assume it was AL, since the frame is AL. Could this piece possibly be steel? Bike is a Spec Rockhopper Comp. The hanger is simply a threaded hole right by the dropout in the chainstay, where the rear derailleur threads into.

How should I have straigtened it? Are you saying that if you bend your integrated hanger (even once) with an AL framed bike, the frame is toast?

A local framebuilder may be able to help you, but it might cost more that the frame is worth. I agree with you that if a derallieur hanger is bent, you have no choice but to realign it, aluminum or not, or you will have shifting and chainskip problems. I also agree with Urban Assault that it might be time for another frame. I'm sure you could find a used frameset at the Rockhopper level or better for a good deal. Good luck.

if you do end up getting a new frame....buy one with replaceable hangers

I don't see any reason that it can't be refitted with a new piece, which could then be reattached with heli-arc. Unless, money is no object!

You will have to retemper the aluminum either way if you add or repair. Aluminum is dependent on its heat treatment for rigidity in that application. Welding, even with Tig/heliarc will alter this condition. The condition you are running into with the current peice is called work-brittelment. There are 2 options for you without going to a new frame or modification.
First, and the one I would be most inclined to do unless there are cracks already(which there could be), is to aneal and reheat treat the dropout. The feasibility is up to you, but the highest the heat needs to be is 900 deg. The cool down is the trick, and likely you will loose a fair bit of paint either way. A good framebuilder or weld shop should be able to perform this process. Doing so(assuming no cracks) will reform the crystaline structure of the aluminum and restore the strenght once treated. Pure anealing will not give strenght, so it has to be done all the way. Mere anealing will make the aluminum like butter.

Second is adding a dropout of similar variety, or even a part of a dropout. This is a precarious task but one that may be more doable to a good welder. It is very important to mind your weld quality and keep the tubing adjacent (3-4 inches)from getting too hot, as this will remove some of the heat treatment. Again, a good welder will be familiar with this.

Another option, which I have done on some bikes is to merely grind the derailleur tab off. Take a low profile derailleur plate(which is usually steel) and bolt it in place. Usually the holes are aligned easily. These plates are not the most common, but they are a simple solution and have a similar effect to the newer replacable hanger without the lengthy process of installing a dropout to match or boring the existing one to fit.

one word...singlespeed

:)

How about using a combined washer/hanger, as works on cheaper department store bikes. Steel, and about 1/16th inch thick, it hooks over the axle, replacing a washer, and accepts deraillier's threaded mounting bolt.

That is a variation of option #3 that I listed. Valid and functional.