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  1. #1
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    Oh the torment...

    You framers, I have access to a TIG,MIG and a lathe. If I start with a frame and modify it to use for touring/trekking/expedition use what would YOU start with? 26" old school frame no suspension. I keep hearing Specialized. Better than Trek,Univega??? Non disk. Surley et al too rich for my blood plus I like to wrench... be kind now.

  2. #2
    Bicycle Repair Man !!! Sixty Fiver's Avatar
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    If you can handle thin walled tubing with the TIG... go nuts.

    Those mid eighties rigid mtbs are all good choices and the only problem is that sometimes they don't need a thing. My 1987 Kuwahara Cascade was essentially a 26 inch wheeled touring bike and required no frame work as everything I wanted was already there and it was just a matter of refitting a few parts.


  3. #3
    Senior Member ftwelder's Avatar
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    A decent MTB frame from the 90's should be plenty strong. I would make sure and find one fairly large compared to what you might use for trails only.
    1886 Surrey machinists Invincible, 1900 Nashua, 1937 Raleigh Golden Arrow, 1938 Raleigh Silver Record, 1951 Armstrong tourmalet, 1970 Motobecane Grand Record, 1971 Raleigh Professional, 1971 Gitane TDF, 1972 Legnano Gran Primio, 1973, Peugeot PX-10, 1975 Roberts, 1984 Battaglin Giro, 1985 Grandis Speciale, 2012 FTW

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  4. #4
    Randomhead
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    Maybe an old GT?

    I would start out with tubes, modifying something is just too much compromise

  5. #5
    THE Materials Oracle Falanx's Avatar
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    I'll second the old Max Mudroom steel Univegas.
    "While my father fought for you, I learnt. While my father glorified your petty administration, I learnt. While he longed every day for our line, Adun’s line, to be restored, I learnt. He sent me away to bring the Dark Templar back when the time was right!
    "And you tell me that I cannot do this? That I cannot feel the weight of the universe?
    "Damn you, Tellan! Aldaris killed my father!"

  6. #6
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    ..any favorites?

    Which Univegas y'all favor?

  7. #7
    Senior Member GrayJay's Avatar
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    MTB frames tend to have freakishly long top-tubes when setup as a road bike. If you select a MTB frame just based on the top-tube length, then the seattube (and headtube) will be very low and require a longish seatpost and very hi-rise stem to get road bars to a comfortable touring position. Bottom Bracket height will also be fairly high in comparison to a purpose built touring bike. A sturdy steel MTB will be nice and stiff for handeling load, just make sure it is not pre-thrashed and ready to crack in half. 26" wheels can be more sturdy/stiff but will be slower if you are staying mostly on pavement.
    A lightweight road frame can definitly be too flexible if you are carrying a load, the extra stiffness of a heavier frame is well worth the weight tradeoff.

    If you are up for a big project, I suppose you might start with a steel MTB with appropriate seattube length, then cut out the headtube, shorten top tube and downtube (to get TT length to fit better) and then add a new taller headtube back in.
    You can also change position of the cantilever bosses if you want to set it up for 700c wheels.

  8. #8
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    You can do what I did for a friend.. start with a cheap heavy frame from the 70s, pick nearly any manufacturer. I took an old Ross frame that somebody left at the LBS, added a bunch of braze-ons, put 9 speed STI, racks, a triple Ultegra groupset, fenders...it has room for at least 35c tires and makes a great touring rig. I'm going to hack it once more soon and update the dropouts to a modern vertical dropout that'll make changing tires less of a pain with the fenders, and I'm going to add disc mounts to it.
    Kendall Frederick

    Orange Park, FL

  9. #9
    Senior Member squirtdad's Avatar
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    Why not look for a frame that need less modification (not sure what you thinking for mods) A lot the japanese basic 12 speeds from the early 80's had more of a touring geometry than race and had at least basic eyelets. think Univega, Nishiki, panasonic, bridgestone
    '82 Nishiski commuter/utility
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    looking for: De Rosa 58cm ELOS frame and fork internal cable routing

  10. #10
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    Much like sixty fiver said, some of the mid to late 80's MTB frames make ideal conversion candidates, requiring little more than adding racks and fenders. I've got an 85 Peugeot Canyon Express that has all the accoutrements of a quality touring bike minus the downtube gear lever bosses and mid fork braze-ons. Check this thread for more info:
    http://www.bikeforums.net/showthread...s-heavy-photos

    Here's one featuring MTB conversions if you're interested:
    http://www.bikeforums.net/showthread...MTB-conversion

  11. #11
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    27" wheel frames with 700c wheels and extra long reach calipers. Typically can fit 35s with fenders, and you get a lower bottom bracket due to the smaller wheel diameter. Longer chainstays give you good heel clearance for bags--probably better than an old MTB frame. Maybe stick a couple extra little braze-ons on there (another bottle cage, fender eyelets, what-have-you.) I did this for a commuter and have been loving it.

    One little additional mod I am thinking about is brazing in a second top-tube, several inches below and parallel to the first top-tube, because my frame is quite tall and therefor a bit noodley. Thinking I could stabilize the main triangle by making it smaller this way.

    Like this:

  12. #12
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    Quote Originally Posted by jharley View Post

    One little additional mod I am thinking about is brazing in a second top-tube, several inches below and parallel to the first top-tube, because my frame is quite tall and therefor a bit noodley. Thinking I could stabilize the main triangle by making it smaller this way.

    Like this:
    /IMG I hate it when people endlessly requote big files)
    I should probably start a new thread asking: Is there any actual evidence that this works?

    Seems a silly way to try to stabilise a flexible structure to me, adding more material where it's least effective (in the middle).

  13. #13
    Randomhead
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    on a 65cm frame like that it might add a little stiffness, smaller frame almost certainly not. There are better places to add weight if you want stiffness

    I think we recently had a thread about the second top tube. If someone was willing to do some simulation or testing, it might help, otherwise it's just speculation. "this isn't an argument, it's a contradiction," "no it isn't"

  14. #14
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    Well then, I will be the first to try it. Adding a top tube to a frame I already know well should provide good evidence.

    I should clarify that what I looking for is not more stiffness in the sense of the bottom bracket moving side to side when you mash on the pedals, but less noodliness or twistability in the front triangle. My front triangle gets really twisty when I make quick steering adjustments...which has been common to every large standard diameter steel tube frame I've ridden.

    Incidentally, my reasoning for the double top tube is that for a large frame (say 63cm and up), you don't really have a front triangle.... you have a 4 sided shape. The difference between a triangle and a four sided shape is that you can twist the latter. The longer the headtube gets, the more it can twist. By adding the lower top tube, I am thinking that you essentially create the less twisty front triangle that short frames have, but still have the height you need.

  15. #15
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    It also occurs to me that most people probably don't know what the hell us tall riders are talking about, since you've not ridden these really tall steel frames before. To try to explain it better, as I am riding along in a straight line, it takes very little effort applied at the handlebar to set up a fairly dramatic front end shimmy in the frame. I can clearly see the head tube and top tube bending left and right when I get this going. It gets annoying/uncomfortable in the situation where you are going pretty fast and have to make a quick steering adjustment. I've had 5 different steel frames of various makes that were 62cm and larger and they have all been like this.

  16. #16
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    Quote Originally Posted by unterhausen View Post
    If someone was willing to do some simulation or testing, it might help, otherwise it's just speculation. "this isn't an argument, it's a contradiction," "no it isn't"
    I agree entirely and was rather hoping that someone had done some modelling.

  17. #17
    Randomhead
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    Actually, some students in the lab I work in measure bike vibration modes and showed that they are well above the vibration frequencies you see in shimmy. I think I may have actually mentioned that earlier in this very thread. You can have a 5'3" rider on a 49 cm frame, and if shimmy starts there is an optical illusion of the tubes bending. They aren't. I used to ride a 55cm frame that would shimmy at the drop of a hat, and it looked like the front of the top tube was bending =/- an inch. If it really was, I would never have ridden that frame.

    That being said, if I was tall I wouldn't mess with standard diameter tubing.

  18. #18
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    Interesting...I agree about tall + standard diameter sucking. But before I could buy or make a custom frame all I could get that were big enough were old steel frames. I'll have to get this little project going soon and give a report. Incidentally, I am building a 64cm frame now with oversize tubing, if I end up with the same situation I might try the double top tube experiment on that too.

    Quote Originally Posted by unterhausen View Post
    Actually, some students in the lab I work in measure bike vibration modes and showed that they are well above the vibration frequencies you see in shimmy. I think I may have actually mentioned that earlier in this very thread. You can have a 5'3" rider on a 49 cm frame, and if shimmy starts there is an optical illusion of the tubes bending. They aren't. I used to ride a 55cm frame that would shimmy at the drop of a hat, and it looked like the front of the top tube was bending =/- an inch. If it really was, I would never have ridden that frame.

    That being said, if I was tall I wouldn't mess with standard diameter tubing.

  19. #19
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    Well...
    I've built up a tourer as follows:
    Schwinn Criss Cross
    22/32/42 chainring Suntour Mech.
    11-34 Shimano Megarange (7sp)
    Rebuilt the Joytech hubs...ug.
    Diacompe brakes (for now)
    Panaracer tires and a...
    WTB seat.
    I have a flatbar with barends right now but
    will be replacing those bits with some Suntour frictions and some NOS
    brakes I found that are "purty."
    Green and brown camo paint.
    Thoughts?

  20. #20
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    "Incidentally, my reasoning for the double top tube is that for a large frame (say 63cm and up), you don't really have a front triangle.... you have a 4 sided shape. The difference between a triangle and a four sided shape is that you can twist the latter. The longer the headtube gets, the more it can twist. By adding the lower top tube, I am thinking that you essentially create the less twisty front triangle that short frames have, but still have the height you need."

    The second tube has to help in that regard, assuming that is even the problem. But it doesn't look overly efficient, since while it creates a real triangle one foot of the tube is pretty much at a point of rotation. I would love to experiment with a tube that broke the main triangle up into smaller triangles, but it would be more beneficial for weight than racking in the frame.

    I was looking at Zinn's site since he specializes in tall frames. I noticed he doesn't do anything unusual in making his frames, just standard tubes. So larger, stronger tubes seems like they would get the job done by themselves, just deploy the normal improvements for heavy riders since taller is heavier by itself.

    If I wanted the frame to be a lot stiffer laterally, I would probably go for much fatter tubes as for aluminum, or some kind of structure a little bit more like a mixte.

  21. #21
    Randomhead
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    Quote Originally Posted by MassiveD View Post
    If I wanted the frame to be a lot stiffer laterally, I would probably go for much fatter tubes as for aluminum, or some kind of structure a little bit more like a mixte.
    you should use the quote function.

    The current way of building mixtes is to drop the top tube and point it towards the rear dropouts, and then continue from the seat tube to the rear dropouts with an extra set of stays. This is because the full length mixte stays don't have as much stiffness and add the same weight. I think adding a second top tube angled towards the dropouts makes sense, and then add a second set of stays to keep that from breaking the seat tube. This makes a lot more sense than adding a tube parallel to the top tube, get some extra triangles from the weight. The French used to build large bikes with full-length mixte stays.

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