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  1. #1
    cdouble
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    Disposable hanger vs Alternator

    Bought myself a geared el mariachi in April. Riding with a buddy last weekend, he picked up a stick and busted his derailleur hanger, it got me thinking about the regulator dropouts. They have an integrated hanger, and the bike shop tells me they are extremely rugged. So now I'm wondering if i have the bad luck my buddy had, is my X9 derailleur going to pay the price? It seems the idea of a cheap, relatively weak "breakaway" hanger has merit. Why did salsa go a different route?

    cdouble
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    cdouble

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  2. #2
    Harmonius Wrench
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    Well, the obvious answer is that the Altenator's main purpose is not as a breakaway hangar. It is primarily a tensioning mechanism for running single speed, and secondarily is a way to alter your wheel base/chain stay length.

    In my years as a mechanic, break away hangars almost never save the derailleur they are attached to. That is not the purpose of a break away hangar anyway. The reason that they were made popular was that they save the frame from becoming dumpster food if you whack a derailleur while riding.

    Previous to break away hangars, many aluminum frames were susceptible to becoming junk if the hangar was bent too far or broken. This wasn't such a big deal with steel frames, where the material was more lenient to bending, and could be repaired relatively inexpensively. Not so with aluminum frames.

  3. #3
    cdouble
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    Yep, I get that and agree that saving the frame is most important. But having seen a couple of hangers break when sticks were sucked into the derailleur (and the derailleur did survive), I can't help but think the hanger also saved the derailleur. After all, the forces were enough to bust the hanger. With a beefier hanger (like the regulator) the frame is definitely safe but I can't help wondering if the derailleur is more likely to get busted up? Why not protect both the frame and the derailleur by using a relatively weak hanger?
    cdouble

    http://mo7s.blogspot.com

    "It never gets easier, you just go faster"
    Greg LeMond

  4. #4
    Harmonius Wrench
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    [QUOTE=cdouble;9598667 Why not protect both the frame and the derailleur by using a relatively weak hanger?[/QUOTE]

    Tough to negotiate that. On one hand, you could make the hangar easier to bend/break, but then you have a hangar that's always bending and breaking. Plus, shifting quality suffers when hangars are softer, easier to bend, and this isn't very acceptable when 10 speed systems are so sensitive to being out of adjustment.

    Or you could make hangars that are really hard and brittle and bust off easier, saving the derailleur, but then you have a hangar that is easier to bust off. You would protect the shifting integrity by doing this though, since the hangar would be less likely to come out of alignment.

    Finally, my thought for saving derailleurs would be to utilize the old trick we used in the 90's on our 8spd rear derailleurs. We would replace the main hangar pivot with an alloy one that was designed to shear off when the derailleur was twisted or yanked backward by a stick, for example. I always thought that was a smarter way to save a derailleur from getting whacked. Unfortunately that isn't an option these days.

    Shimano's new Direct Mount may be an answer here though, but as of now, it is too new and no designed fail mode has been offered for derailleur protection. I could see how it might be done though.

    I'm rather skeptical about any high percentage derailleur saving devices coming to market though. It would seem that bending forces typically will pull a derailleur into the rear wheel anyway, and with the chain linked through this component, saving a derailleur intact from stick, stone, or crash damage is going to be rarer than destruction of the component in my opinion.

    In light of this, I would rather see a hangar that saves my frame first. If the derailleur makes it through unscathed, that is gravy.

  5. #5
    cdouble
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    Makes sense. Maybe I'll just grow a pair, run it as a single speed, and stop fretting.

    Thanks

    cdouble
    http://mo7s.blogspot.com
    cdouble

    http://mo7s.blogspot.com

    "It never gets easier, you just go faster"
    Greg LeMond

  6. #6
    Birthday Collector
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    Quote Originally Posted by Guitar Ted View Post
    In light of this, I would rather see a hangar that saves my frame first. If the derailleur makes it through unscathed, that is gravy.
    I agree 100% - first, save the frame, then worry about being able to re-use the derailleur. Cascading value-of-items logic. Seeing a lot of bikes with weak hangers as the MFR's play with designs. I think the strong and stiff but brittle hanger is the way to go, with the frame material that the hanger is attached to being a bit thicker and stronger than the hanger, and hopefully just a bit maleable/flexible as the impact/chain suction that breaks the hanger sometimes still puts a load on the frame and they get tweaked a bit... The Alternator drop outs are thick, pretty beefy aluminum. It may bend back after a tweak (if the derailleur survived!) With the adjustable chain-stay length, the derailleur breaks, you SS it out. The Alternator drive-side drop outs are not expensive - the same or lower price as a lot of hangers.

    First off, hopefully you miss that rock/stump/branch and don't tweak things, but in reality it's a good idea to carry a spare hanger or one of the generic emergency hangers. It might at least give you a spot to mount a mangled rear derailleur as a chain tensioner to SS it out... If I start riding geared again this winter I'll toss one in the seatpack. IF I start riding geared again!
    R.I.P. Corky 10/97-4/09
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  7. #7
    mtbr member
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    Quote Originally Posted by ATBScott View Post
    ...but in reality it's a good idea to carry a spare hanger or one of the generic emergency hangers.
    Carrying a spare Alternator dropout is asking a lot. I do carry a generic hanger in my pack, but that's of no use with my El Mariachi. It is useful on my other bikes though.

  8. #8
    Harmonius Wrench
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    Quote Originally Posted by JonathanGennick View Post
    Carrying a spare Alternator dropout is asking a lot. I do carry a generic hanger in my pack, but that's of no use with my El Mariachi. It is useful on my other bikes though.
    It's not as big of a deal as you might think. I've carried an Altenator spare before for my Ti Muk and it's no bother at all. They are super-simple to install, probably easier than many replaceable drop outs, since the bolts are so big and you use standard sized Allen bolts and not fiddly chain ring bolt based fasteners, or tiny screws. In my opinion anyway.

  9. #9
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    I just stripped the threads in the 'swing plate fixing bolt' on the non-driveside assembly of my Selma Ti.

    Guitar Ted, do you know the most efficient way I can get my hands on a replacement? You think it would it be covered under the warranty of the frame? (not that a warranty claim is the fastest way to do anything)

    Hoping not to miss this weekend's 35 miler...
    Selma Ti.

  10. #10
    Harmonius Wrench
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    Quote Originally Posted by adinpapa View Post
    I just stripped the threads in the 'swing plate fixing bolt' on the non-driveside assembly of my Selma Ti.

    Guitar Ted, do you know the most efficient way I can get my hands on a replacement? You think it would it be covered under the warranty of the frame? (not that a warranty claim is the fastest way to do anything)

    Hoping not to miss this weekend's 35 miler...
    Order a replacement hangar through QBP/your nearest LBS tomorrow. That probably won't be a warranty issue, since it isn't necessarily a material defect.

    A temporary fix might be to get a longer bolt and secure it on the back side with a nut and lock washer, which may work on the non-driveside only.

  11. #11
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    Thanks. The bolt solution will enable to get out with the crew this evening to celebrate the first Autumn-like day here in Western MA.
    Selma Ti.

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