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  1. #1
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    Can a Bent Dropout be Saved?

    There is a difference in gap spacing between the Right / Left Dropouts.
    What do I do? Jury rig attaching a derailleur w/adapter claw?

    Right / Left Dropouts /
    http://www.liquidfusion.net/Peugeot/U08-4L9A.JPG
    http://www.liquidfusion.net/Peugeot/U08-5L9A.JPG

    The Suntour Cyclone Rear Derailleur (as it was setup):
    http://www.liquidfusion.net/Peugeot/U08-14LCA.JPG

    The Suntour Cyclone Rear Derailleur showing bent alignment:
    http://www.liquidfusion.net/Peugeot/U08-10LCA.JPG
    http://www.liquidfusion.net/Peugeot/U08-12LCA.JPG


    My bike:
    http://www.liquidfusion.net/Peugeot/UO8-1LC9.JPG
    http://www.liquidfusion.net/Peugeot/UO8-3LC9.JPG

    http://www.bitrot.de/bbook_drive.html
    It is absolutely critical to adjust the limit screws of rear derailleurs precisely. If the chain overshifts and falls off the smallest cog, it may block the wheel. If it overshifts at the other end, the derailleur might get caught in the spokes, which will probably crush or snap the derailleur in half and bend the dropout of the frame. A good mechanic may be able to bend the dropout back into shape (this requires special and very expensive frame alignment tools) but this is an excellent way of destroying frames.
    Last edited by Liquidfusion; 01-01-07 at 03:39 PM.

  2. #2
    cab horn
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    Well, either try resetting the derailleur hanger yourself or i'd bin it.
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  3. #3
    biked well well biked's Avatar
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    It appears the dropout is bent and will need to be straightened, and that the adapter claw derailleur hanger is also bent, and will need to be replaced. A shop would probably align the dropout for you for a few bucks, or you might be able to do it yourself using a large adjustable wrench, although you will have to rely on "eyeballing it" in doing it that way. I think www.loosescrews.com carries replacement adapter claws that should work-

  4. #4
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    Thought came to my mind --- if the derailleur / adapter claw were already on the bike, then the dropout was bent a long time ago!!! When you say "align the dropout," do you mean narrow the gap? If I get an adapter claw, then I can leave this dropout alone and not risk breaking the frame.

    This experience reminds me of rebuilding a Triumph Spitfire way back when......

  5. #5
    biked well well biked's Avatar
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    Quote Originally Posted by Liquidfusion
    Thought came to my mind --- if the derailleur / adapter claw were already on the bike, then the dropout was bent a long time ago!!! When you say "align the dropout," do you mean narrow the gap? If I get an adapter claw, then I can leave this dropout alone and not risk breaking the frame.

    This experience reminds me of rebuilding a Triumph Spitfire way back when......
    It appears from the photos the dropout is bent in two different ways, with the space where the axle slides in being spread apart more than it's supposed to be, and also the face of the dropout is bent inward. When I said "align the dropout" I was referring to the face of the dropout being aligned, I really didn't mention anything about the other issue, although I should have. I think to get smooth, reliable shifting, even with friction shifters, you'll need to align the face of the dropout, and of course you'll also have to bend the dropout back so that the space where the axle goes is the correct dimension for the axle nut to be tightened down against it. And then you'll still need a new adapter claw, unless you can bend that back, too-

  6. #6
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    to align the face of the dropout
    Ok I see the need for that.

    to bend the dropout back so that the space where the axle goes is the correct dimension for the axle nut to be tightened down against it.
    Frame is steel - magnets don't fall off. Do I need to bring this to a frame builder to bend in the dropout? Can it be jury rigged well enough with the adapter claw?

    Possibly when I changed gears, the rear derailleur wasn't fastened securely and therefore the adapter claw on the bike was not clamped down right. Maybe that's why it all jammed even though I was going slow on a flat surface road. There's alot happening when you change gears!!!

  7. #7
    biked well well biked's Avatar
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    Quote Originally Posted by Liquidfusion
    to align the face of the dropout
    Ok I see the need for that.

    to bend the dropout back so that the space where the axle goes is the correct dimension for the axle nut to be tightened down against it.
    Frame is steel - magnets don't fall off. Do I need to bring this to a frame builder to bend in the dropout? Can it be jury rigged well enough with the adapter claw?

    Possibly when I changed gears, the rear derailleur wasn't fastened securely and therefore the adapter claw on the bike was not clamped down right. Maybe that's why it all jammed even though I was going slow on a flat surface road. There's alot happening when you change gears!!!
    Steel is really the only frame material you could do these types of repairs on. I'd take the bike into a bike shop and see if they can help you out with this. I think it's likely they can at least get it aligned for you, but I'm not sure what method would be best for bending the dropout back up so that it's shaped properly to accept the axle, adapter claw, and nut. If it were mine I'd probably take a hammer and a block of wood and see if I could bend it back into shape. And as for the alignment, I think you could use a large adjustable wrench to get it straight, but again, for a few bucks it might be worth it to let a bike shop do at least that part of it for you-

  8. #8
    Senior Member masi61's Avatar
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    Quote Originally Posted by well biked
    It appears from the photos the dropout is bent in two different ways, with the space where the axle slides in being spread apart more than it's supposed to be, and also the face of the dropout is bent inward. When I said "align the dropout" I was referring to the face of the dropout being aligned, I really didn't mention anything about the other issue, although I should have. I think to get smooth, reliable shifting, even with friction shifters, you'll need to align the face of the dropout, and of course you'll also have to bend the dropout back so that the space where the axle goes is the correct dimension for the axle nut to be tightened down against it. And then you'll still need a new adapter claw, unless you can bend that back, too-
    I thought it looked bent 2 different ways as well. Sorry to say but the frame looks pretty cheap with just the basic dropouts and no built-in ear for the rear derailleur. Unless the frame holds a lot of sentimental value I wouldn't hesitate to give it a go in my own shop. If you have a big machinist vice securely mounted to a bench you could mash the dropout face flat, then once very tight, just bend the rest of the frame as the dropout remains stationary in the vice. Eyeball it until it appears parallel to the front fork dropouts or until your derailleur pulleys are in line with the freewheel cogs with the derailleur remounted.
    You're going to need to close that gap where the drop out opens downward. How in the world did it get that way BTW? Not sure how to achieve that. If you were successful with the vice technique I might even go back to the vice and try to carefully close that gap. If not, you could always take a hammer and a big drift pin and whack on it until it submits. Those dropouts look stamped, not forged which to me means they are somewhat maleable.
    Just had to ask, What's the deal with the funky handlebars?
    Good luck.

  9. #9
    Senior Member Retro Grouch's Avatar
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    If you have average or better mechanical ability, you can do this. Just clamp a big crescent wrench onto the individual parts and bend them back straight. On a 5 or 6-speed bike with index shifting it doesn't have to be perfect.

  10. #10
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    I'm not sure what method would be best for bending the dropout back up so that it's shaped properly to accept the axle, adapter claw, and nut.
    Seems to me this is critical to get right before adding another rear derailleur back on.

    If it were mine I'd probably take a hammer and a block of wood and see if I could bend it back into shape.
    Where would you put the wood? How would you do this?

    You're going to need to close that gap where the drop out opens downward. How in the world did it get that way BTW?
    Don't know either. Bike is a recent gift from a friend who can't ride. Said he had a fall a few years ago. No vice grip here.

    take a hammer and a big drift pin and whack on it until it submits.
    Please describe more....... wack the metal dropout from the bottom to close the gap? What's a drift pin?

    If you have average or better mechanical ability, you can do this.
    removed the rear derailleur / opened it / removed the chain / reassembled it all back again - OK on this

    Just clamp a big crescent wrench onto the individual parts and bend them back straight.
    This takes care of sideways vertical alignment. What about closing the fork / dropout "gap?"

    BTW a bike shop here that does repair said they can do this for ~ $8.00. I asked are they experienced? They said yes.
    Right now getting all info before making a move.

    Thanks / Brewer

    PS

    Just had to ask, What's the deal with the funky handlebars?
    Italian "Bullhorns" !!!! They were put on high like this as the person who used to own the bike had back pblms.
    Last edited by Liquidfusion; 01-02-07 at 11:10 AM.

  11. #11
    biked well well biked's Avatar
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    Quote Originally Posted by Liquidfusion
    I'm not sure what method would be best for bending the dropout back up so that it's shaped properly to accept the axle, adapter claw, and nut.
    Seems to me this is critical to get right before adding another rear derailleur back on.

    If it were mine I'd probably take a hammer and a block of wood and see if I could bend it back into shape.
    Where would you put the wood? How would you do this?

    You're going to need to close that gap where the drop out opens downward. How in the world did it get that way BTW?
    Don't know either. Bike is a recent gift from a friend who can't ride. Said he had a fall a few years ago. No vice grip here.

    take a hammer and a big drift pin and whack on it until it submits.
    Please describe more....... wack the metal dropout from the bottom to close the gap? What's a drift pin?

    If you have average or better mechanical ability, you can do this.
    removed the rear derailleur / opened it / removed the chain / reassembled it all back again - OK on this

    Just clamp a big crescent wrench onto the individual parts and bend them back straight.
    This takes care of sideways vertical alignment. What about closing the fork / dropout "gap?"

    BTW a bike shop here that does repair said they can do this for ~ $8.00. I asked are they experienced? They said yes.
    Right now getting all info before making a move.

    Thanks / Brewer

    PS

    Just had to ask, What's the deal with the funky handlebars?
    Italian "Bullhorns" !!!! They were put on high like this as the person who used to own the bike had back pblms.
    In regard to the block of wood and hammer, I meant that the block of wood would be placed at the bottom front edge of the dropout, and by hitting it with a hammer you might be able to bend the dropout back into shape. Obviously the bike would need to be secured or at least stable when you do this, as well as upside down. It might work, it might not, but it would be the first thing I would try. Masi61's suggestion is probably better, use a hammer and drift pin or something similar, this would be more inclined to bend the dropout I think. A drift pin is basically a metal punch, with enough flat surface on the end to be useful for something like this. They're usually made of a soft metal such as brass so that they don't mar the surface of whatever harder metal they're in contact with. If the wood or drift pin doesn't work, I'd probably hit it directly with a hammer, that would surely bend it although it might mangle the dropout some.........With all of that said, if a bike shop is willing to do all of this for $8, I'd go for it. As Retro Grouch said, this is not a job that needs to be absolutely perfect to get good shifting with friction shifters. The main thing I'd be concerned with is that the dropout gets reshaped so that it will hold the axle securely-

  12. #12
    feros ferio John E's Avatar
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    It's a UO-8, and the dropouts are malleable stamped steel. You can easily close the dropout gap with either a rubber mallet or a vise. Work carefully and watch what you are doing, and you are unlikely to damage anything. Been there ... done that.
    "Early to bed, early to rise. Work like hell, and advertise." -- George Stahlman
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  13. #13
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    You can easily close the dropout gap with either a rubber mallet or a vise. Work carefully and watch what you are doing, and you are unlikely to damage anything. Been there ... done that.
    Great Advise!!

    OK Here is what I did / Thanks to all who helped!!!! Waiting for the rear derailleuir to arrive.

    Full View both dropouts (from above):
    http://www.liquidfusion.net/Peugeot/U08-RD6L9.JPG

    Are these ok?

    Left side:
    http://www.liquidfusion.net/Peugeot/U08-RD4L9.JPG

    Right Side (Flywheel/Derailleur side):
    http://www.liquidfusion.net/Peugeot/U08-RD3L9.JPG

    Hammered Dropout (used crescent wrench / heavy rubber hammer):
    http://www.liquidfusion.net/Peugeot/U08-RD2L9.JPG
    http://www.liquidfusion.net/Peugeot/U08-RD1L9.JPG

  14. #14
    Non Tribuo Anus Rodentum and off to the next adventure (RIP) Stacey's Avatar
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    Smokin'!

    You can now trade in your n00b badge for a well earned Rookie badge.

    Congrats!

  15. #15
    Senior Member masi61's Avatar
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    Sweet! They look entirely normal now.
    Good job!

  16. #16
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    Thanks!!

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