Advertise on Bikeforums.net



User Tag List

Page 1 of 2 12 LastLast
Results 1 to 25 of 28
  1. #1
    Newbie
    Join Date
    Jul 2008
    Posts
    2
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    criterium geometry?

    Greetings. I need a road bike for 1 or two day trips. And I have a chance to buy a mid 80's cannondale roade bike with what is described as 'criterium geometry'. He refers to it as a Black Beauty, but I dont think that's a model name. Would this kind of setup work for what I have described? Thanks for any help, Harry O.

  2. #2
    Senior Member
    Join Date
    May 2000
    Location
    Edmond Oklahoma
    Posts
    106
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If you mean 1 or 2 day tours, then stay away. Those mid 80's Cannondales were bone shakers, and the "crit" geometry is wrong as well.

    Zagnut

  3. #3
    Senior Member Nessism's Avatar
    Join Date
    Jun 2004
    Location
    Torrance, CA
    My Bikes
    Homebuilt steel
    Posts
    2,324
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    One of the stiffest frames ever made. Poor choice for a long distance cruiser.
    Becareful buying/selling bike parts on-line. I learned the hard way. :(

    Good/Bad Trader Listing

  4. #4
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Buy a carbon fiber or touring bike

    Hi, these guys are totally right.

    I know, because I own one! Mine was a leftover from the canadian olympic team, that I got unused somewhere around 1985. I had selected it because in those years, I liked to do hills, and my Columbus-SL+SP Vicini was starting to fatigue, flex, and shift gears without my conscent on the climbs.
    The Cannondale certainly is amazingly rigid, as I still own it. But this bike is hard on your back, very hard...

    If you intend to do lots of hills, look for an aluminum bike with NON-aero downtube (structurally, a flattenned tube is the poorest performing, with the triangular and clover cross-sections a close stupid behind), and it having a bent/S-curved seat stays (perhaps out of carbon fiber) would really help on bumpy roads (the seat stays don't contribute all that much during the pedal stroke to pedalling efficiency and are well suited for vibration-dampening design).
    If you are a former racer and miss quick-handling bikes, this will give you the best of both worlds... stiffness for climbing those hills, yet comfort in riding.

    If you go for a full carbon bike, be careful... too many models have too little material around the bottom bracket, and might not be suitable for a heavy, strong rider, riding hard or doing hills with a bunch of gear on the luggage racks.

    Also make sure you get yourself a GOOD seat. Do not under-estimate the importance of that. Padded gel seats can be pretty bad, if they are too wide because your leg will hit on the downstroke and there can be too little support in the nose versus the back cushion area... make sure you get something that fits for your gender. Also the nose has to point up slightly, so your body naturally slides back onto the cushioned area (or you will be applying extra weight on the handlebars to push yourself back onto the seat's cushioned area, thus potentially injuring the nerve in your palms (ulnar nerve I believe)).
    A shockpost probably isn't a bad idea... but it adds a lot of weight, and some of them have side-flex, which is energy-robbing... carbonfiber seatposts might be a better idea as they can be found relatively cheap now.

    If any of you is interested in a super stiff Cannondale, I'm selling mine, as I have too many bikes... have just acquired a recumbent, and as I'm too old to race or do serious riding, as my knees and back wouldn't forgive me, so I'd part with the Cannondale. Ironically, these frames DID come with eyelets, so you'd be able to add luggage racks without damage to the frame. It is for tall strong riders (I am 6ft2, and would consider 6ft1 the minimum), and equipped with a collection of the lightest equipment that could be found in that day (LOL no not campy super, lighter than that!).
    Last edited by Timmi; 07-24-08 at 11:11 AM. Reason: more info

  5. #5
    Senior Member Nessism's Avatar
    Join Date
    Jun 2004
    Location
    Torrance, CA
    My Bikes
    Homebuilt steel
    Posts
    2,324
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    Hi, these guys are totally right.

    I know, because I own one! Mine was a leftover from the canadian olympic team, that I got unused somewhere around 1985. I had selected it because in those years, I liked to do hills, and my Columbus-SL+SP Vicini was starting to fatigue, flex, and shift gears without my conscent on the climbs.
    The Cannondale certainly is amazingly rigid, as I still own it. But this bike is hard on your back, very hard...

    If you intend to do lots of hills, look for an aluminum bike with NON-aero downtube (structurally, a flattenned tube is the poorest performing, with the triangular and clover cross-sections a close stupid behind), and it having a bent/S-curved seat stays (perhaps out of carbon fiber) would really help on bumpy roads (the seat stays don't contribute all that much during the pedal stroke to pedalling efficiency and are well suited for vibration-dampening design).
    If you are a former racer and miss quick-handling bikes, this will give you the best of both worlds... stiffness for climbing those hills, yet comfort in riding.

    If you go for a full carbon bike, be careful... too many models have too little material around the bottom bracket, and might not be suitable for a heavy, strong rider, riding hard or doing hills with a bunch of gear on the luggage racks.

    Also make sure you get yourself a GOOD seat. Do not under-estimate the importance of that. Padded gel seats can be pretty bad, if they are too wide because your leg will hit on the downstroke and there can be too little support in the nose versus the back cushion area... make sure you get something that fits for your gender. Also the nose has to point up slightly, so your body naturally slides back onto the cushioned area (or you will be applying extra weight on the handlebars to push yourself back onto the seat's cushioned area, thus potentially injuring the nerve in your palms (ulnar nerve I believe)).
    A shockpost probably isn't a bad idea... but it adds a lot of weight, and some of them have side-flex, which is energy-robbing... carbonfiber seatposts might be a better idea as they can be found relatively cheap now.

    If any of you is interested in a super stiff Cannondale, I'm selling mine, as I have too many bikes... have just acquired a recumbent, and as I'm too old to race or do serious riding, as my knees and back wouldn't forgive me, so I'd part with the Cannondale. Ironically, these frames DID come with eyelets, so you'd be able to add luggage racks without damage to the frame. It is for tall strong riders (I am 6ft2, and would consider 6ft1 the minimum), and equipped with a collection of the lightest equipment that could be found in that day (LOL no not campy super, lighter than that!).
    Sorry to nitpick but have to comment…

    It’s a metallurgical fact that steel frames do NOT get soft with age such as you reference with your old Columbus frame. Not sure what was going on with it changing gears as you say but it had nothing to do with steel fatigue. Most likely one of the brazed joints was about to come apart or something to this effect.

    Regarding comfort of a frame with “S shaped carbon seat stays”, carbon does help damp vibration but there needs to be motion/movement in the tubes for there to be damping. Reality is that the seat stays, even S shaped ones, don’t move very much at all, thus there is no movement to damp. Best the carbon can do is take out a little of the tingle in the ride, which while comforting, is nothing compared to a springy front triangle where there is more displacement in the vibrations.

    Regarding the aero down tube comments…agree 100%. Tall oval down tubes are the worst possible shape to stiffen the bottom bracket area of the frame since the major axis of the tube is oriented in the wrong direction. Who ever came up with that idea, other than maybe for a time trial frame, was not taking account of the true loads in the tubes.
    Becareful buying/selling bike parts on-line. I learned the hard way. :(

    Good/Bad Trader Listing

  6. #6
    Senior Member
    Join Date
    Jan 2005
    Location
    Baltimore, MD
    Posts
    662
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    I hear you, regarding your metallurgical theories...
    do you own the latest Machinery Handbook by any chance?
    Because I do... and this was part of my studies actually. So I hope you're just not shooting off without the actual knowledge. Don't mean to offend you or anything, serious, just that you get a lot of that.

    "Facts" and "theory" aside, you can talk to any pro rider from the 80's, 90's, and old school expert, and they will ALL testify that steel frames DO fatigue. Not in the sense of aluminum where aluminum fails... but in the sense that it DOES flex more.

    Yes, I know that structurally it is a pipe... hence it's not "logical"... but if you take a piece of steel and bend it back and forth enough, it eventually becomes softer. Don't tell me you've NEVER broken a paperclip this way or other metal pbject. Extrapolate, and it becomes possible that a pipe as well, eventually gets softer with time.

    BTW, you can read up in vintage cycling print about this phenomena... in back issues of bicycling magazine, Bike Tech, and a whole bunch of other cycling publications. It's a general knowledge in the cycling industry... of course, with the pros riding carbon since a decade now, and before that aluminum or titanium, we haven't heard talk about that in a long time.
    A flexed paper clip doesn't become softer, it becomes harder. The clip breaks where the metal has become so hard and brittle that it can't stand any more flexing. Has the term "work hardening" come up in the course of your studies?

  7. #7
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    OK whatever, dwell on words if you like.
    Don't be a jerk. You know what I mean and what I'm talking about.

  8. #8
    Wheelsuck Fat Boy's Avatar
    Join Date
    Jun 2007
    Posts
    6,159
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    OK whatever, dwell on words if you like.
    Don't be a jerk. You know what I mean and what I'm talking about.
    Yes and it has nothing to do with what you're talking about. The modulus (stiffness) of steel (or anything that I know about) does not change because of work hardening.

    People ride steel bikes with 100,000 miles on them. If fatigue was going affect stiffness, it'd be set in by then. Now if a steel bike is made from very thin walled tubing, it may be prone to fatigue failure (the same as aluminum), but that's a different thing entirely.
    Austin doesn't have hippies. They have slightly rebellious Methodists. - Racer Ex

  9. #9
    ride lots be safe Creakyknees's Avatar
    Join Date
    Jan 2007
    Location
    Texas
    Posts
    5,133
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    back to the topic at hand.

    if you want to do tours like that, get a frame described as "sport touring" or "touring"

    you'll be able to spot it by some or all of these features:
    - brazed-on mounting eyelets for racks and/or fenders, ideally front and rear
    - longer chainstays (bigger gap between rear tire and seat tube)
    - larger clearance for larger tires (up to 32c width, or larger even)
    - maybe cantilever brakes
    - triple crankset
    - able to get handlebar tops level with seat, or higher, without kludgy stem tricks.
    - sold / described with terms like "touring", "relaxed", "comfortable"

  10. #10
    Senior Member Nessism's Avatar
    Join Date
    Jun 2004
    Location
    Torrance, CA
    My Bikes
    Homebuilt steel
    Posts
    2,324
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    I hear you, regarding your metallurgical theories...
    do you own the latest Machinery Handbook by any chance?
    Because I do... and this was part of my studies actually. So I hope you're just not shooting off without the actual knowledge. Don't mean to offend you or anything, serious, just that you get a lot of that.

    "Facts" and "theory" aside, you can talk to any pro rider from the 80's, 90's, and old school expert, and they will ALL testify that steel frames DO fatigue. Not in the sense of aluminum where aluminum fails... but in the sense that it DOES flex more.

    Yes, I know that structurally it is a pipe... hence it's not "logical"... but if you take a piece of steel and bend it back and forth enough, it eventually becomes softer. Don't tell me you've NEVER broken a paperclip this way or other metal pbject. Extrapolate, and it becomes possible that a pipe as well, eventually gets softer with time.

    BTW, you can read up in vintage cycling print about this phenomena... in back issues of bicycling magazine, Bike Tech, and a whole bunch of other cycling publications. It's a general knowledge in the cycling industry... of course, with the pros riding carbon since a decade now, and before that aluminum or titanium, we haven't heard talk about that in a long time.

    First of all, I'm a mechanical engineer and have worked in the field for 23 years so far...

    It is not a "theory", it is fact that the elasticity of steel does not change as it's used. The metal can eventually fatigue, after a LOT of cycles, and said fatigue typically shows up as a crack in the metal. Most typical frames from the days of SL, 531, etc, will last for tens of thousands of miles before any fatigue issues show up. Typically, when these frames fail it's not actually true fatigue of the metal, rather these frames typically fail in the heat effected zone of the tubes due to heat reducing the properties of the metal. At any rate, the frames do not "go soft" so forget about that.

    The paper clip example is not appropriate here since bending the clip results in exceeding the metals YIELD point (the point where permanent deformation occurs). A frame will never see loads high enough to cause permanent bending.

    Funny that these old urban legends won't go away. There is evidence on the internet if you want to read more. Found this post if you care to read. http://stason.org/TULARC/sports/bicy...oing-soft.html
    Last edited by Nessism; 07-28-08 at 09:47 PM.
    Becareful buying/selling bike parts on-line. I learned the hard way. :(

    Good/Bad Trader Listing

  11. #11
    Wheelsuck Fat Boy's Avatar
    Join Date
    Jun 2007
    Posts
    6,159
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    I hear you, regarding your metallurgical theories...
    do you own the latest Machinery Handbook by any chance?
    Because I do... and this was part of my studies actually........


    "Facts" and "theory" aside.....
    I'm curious, what does The Machinery Handbook say about the modulus of a material after work hardening.

    I love the "Facts" and "theory" sentence. If we set "Facts" aside, it's easy to make some pretty wild claims. Now we don't want to actually verify those claims with real world testing, do we? Of course not! We would much rather take people's opinions who are 'willing to testify' to something they have never actually tested.

    Really? You actually wrote that? Amazing.
    Austin doesn't have hippies. They have slightly rebellious Methodists. - Racer Ex

  12. #12
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    OK guys look, I was only trying to speak in cyclists terms... about the FEEL of the bike, damn it!

    Using the same terms cycling pros and conoisseurs will use so they understand it... my intent was NEVER to satisfy metallurgists or mechanical engineers, but to speak with cyclists about cycling. If you want to know what the machinery handbook says, buy one, because if you don't have one you were obviously speaking way over your head.


    I was talking about a frame starting to feel "soft and flexible"!!!
    I don't give a flying *** about what is actually happening on the atomic structure level - that is not the topic of discussion here!

    Remember, this is a cycling forum, not a metallurgy class. Do you understand the nuance???

    Now stop being jerks and get back on topic!
    Last edited by Timmi; 08-04-08 at 03:43 PM.

  13. #13
    Senior Member Nessism's Avatar
    Join Date
    Jun 2004
    Location
    Torrance, CA
    My Bikes
    Homebuilt steel
    Posts
    2,324
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    OK guys look, I was only trying to speak in cyclists terms... about the FEEL of the bike, damn it!

    Using the same terms cycling pros and conoisseurs will use so they understand it... my intent was NEVER to satisfy metallurgists or mechanical engineers, but to speak with cyclists about cycling. If you want to know what the machinery handbook says, buy one, because if you don't have one you were obviously speaking way over your head.


    I was talking about a frame starting to feel "soft and flexible"!!!
    I don't give a flying *** about what is actually happening on the atomic structure level - that is not the topic of discussion here!

    Remember, this is a cycling forum, not a metallurgy class. Do you understand the nuance???

    Now stop being jerks and get back on topic!


    Simple FACT is that steel does not go soft with use, period. And it doesn’t start to “feel" soft either. Call Freud if you need an explanation as to what “cycling pros and connoisseurs” are experiencing since it’s all in their heads.
    Last edited by Nessism; 08-04-08 at 10:10 PM.
    Becareful buying/selling bike parts on-line. I learned the hard way. :(

    Good/Bad Trader Listing

  14. #14
    shut up and ride
    Join Date
    Nov 2005
    Location
    noho
    My Bikes
    supersix hi-mod,burley duet tandem,woodrup track,cannondale cross,specialized road
    Posts
    1,942
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Nessism View Post
    First of all, I'm a mechanical engineer and have worked in the field for 23 years so far...
    n00b j/k

    just wanted to thank you for all your posts on all topics, i enjoy reading them, even if others don't seem to get the same enjoyment and informative value out of them that i do

  15. #15
    Senior Member Road Fan's Avatar
    Join Date
    Apr 2005
    Location
    Ann Arbor, MI
    My Bikes
    Terraferma 650b, Mondonico SL and ELOS, Masi Gran Criterium, Trek 610, Breezer Liberty, Georgena Terry Classic
    Posts
    11,212
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Some of us are lovers of cycling who are also engineers and perhaps metallurgists, and are interested in understanding both how a frame feels and why it feels that way. There really isn't any room for setting aside truth and factual accuracy.

  16. #16
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    whatever.

    I think there is a discussion forum regarding metallurgy on the internet somewhere... I'm sure...

    my post was NOT for that audience... I know where I am, and I don't need a GPS for that!

  17. #17
    Member
    Join Date
    Aug 2008
    Posts
    28
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I had an SL frame and I thought that I turned it into a wet noodle because it had started shifting under pressure. I found it was because the pivots and the bushings in my rear deraileur were way worn. I replaced the rear deraileur and viola.
    Also rim flex is a big contributor to percieved rim flex. . . . . errr frame flex
    Last edited by CurbDestroyer; 08-25-08 at 11:29 PM.

  18. #18
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by CurbDestroyer View Post
    I had an SL frame and I thought that I turned it into a wet noodle because it had started shifting under pressure. I found it was because the pivots and the bushings in my rear deraileur were way worn. I replaced the rear deraileur and viola.
    Also rim flex is a big contributor to percieved rim flex.
    I have lots of expensive parts, all kept in perfect condition... and I have plenty of derailleurs to choose from. Cables are replaced regularly. Lugs-to-tube joints are perfect - brazing done by Vicini was flawless - this man was meticulous - "extremist-meticulous"! I saw the joints when I did a new paintjob before giving the frame to my dad - full penetration, no gaps. I was a bike mechanic, bike racer, and team trainer - there isn't the remotest possibility of a mechanical issue here. Summed up, all the parts I have are pro parts and together might be worth more than your car.

    Also, I build all my wheels... they never come tight enough for my liking when you buy them built. Mine are at the maximum tension a spoke+nipple can take. Definitely not a factor here.

    I am definitely talking about tubes flexing more than when the bike was new.
    Last edited by Timmi; 08-18-08 at 10:14 AM.

  19. #19
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Nessism View Post
    Simple FACT is that steel does not go soft with use, period. And it doesn’t start to “feel" soft either. Call Freud if you need an explanation as to what “cycling pros and connoisseurs” are experiencing since it’s all in their heads.
    Typical engineer arrogance and narcissism.
    You probably tell your dentist how to do his job when you go see him.
    Because you have an engineer's-complex and don't believe that ordinary mortals can posess intelligence, which shows each time that you don't value anyone else's opinion, each time you discount the value of life experience and wisdom... the engineer is the know-all and end-all of all things, isn't he? He creates, thus it makes him better. (And the rest of us are stuck with your crappy flawed designs!)

  20. #20
    Senior Member Road Fan's Avatar
    Join Date
    Apr 2005
    Location
    Ann Arbor, MI
    My Bikes
    Terraferma 650b, Mondonico SL and ELOS, Masi Gran Criterium, Trek 610, Breezer Liberty, Georgena Terry Classic
    Posts
    11,212
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    Typical engineer arrogance and narcissism.
    You probably tell your dentist how to do his job when you go see him.
    Because you have an engineer's-complex and don't believe that ordinary mortals can posess intelligence, which shows each time that you don't value anyone else's opinion, each time you discount the value of life experience and wisdom... the engineer is the know-all and end-all of all things, isn't he? He creates, thus it makes him better. (And the rest of us are stuck with your crappy flawed designs!)
    People are trying to share their ideas. No body needs your negativity. Everyone wants your thoughts and experiences.

    If you don't think metallurgy is a valid science, why hasn't the Golden Gate Bridge fallen down or gone noodly yet? Its materials are really really similar to those in your Vicini-built frame and it's much older.

    Road Fan

  21. #21
    Senior Member Timmi's Avatar
    Join Date
    Jul 2008
    Location
    born in Europe, living in Montreal Canada
    My Bikes
    Vicini road racing, Canondale canadian olympic team frame (1984) with Ofmega Mistral and other cool vintage ultralight components on it, Specialized RockHopper, Cambio Rino track bike (Gipiemme equipped), swb recumbent.
    Posts
    121
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Respect for your forefathers

    Quote Originally Posted by Road Fan View Post
    People are trying to share their ideas. No body needs your negativity. Everyone wants your thoughts and experiences.

    If you don't think metallurgy is a valid science, why hasn't the Golden Gate Bridge fallen down or gone noodly yet? Its materials are really really similar to those in your Vicini-built frame and it's much older.

    Road Fan
    I understand.

    But what got us here, is total disrespect for wisdom from those older and more experienced than us.

    I do believe that theory always has to be verified in the field.

    In this case, we're not talking about the golden gate bridge, but of thin-walled bicycle tubing, and what experienced riders have as experience with them.

    The day that Bernard Hinault or Gred Lemond or one of the old-school guys throws the book of metallurgy at me, I'll bow out gracefully. But it is those very professionals that report frames fatiguing... and they had access to illimited-budget frame-building.

    And I know when to set aside theory and give a little respect to those who have gone farther than myself, who have more experience than myself, and who have perhaps experienced things that cannot be measured.

    "Not everything that counts can be measured. And not everything that can be measured counts."
    --Albert Einstein.

  22. #22
    Wheelsuck Fat Boy's Avatar
    Join Date
    Jun 2007
    Posts
    6,159
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tigrrrtamer View Post
    I do believe that theory always has to be verified in the field.
    Steel isn't exactly a new material.
    Austin doesn't have hippies. They have slightly rebellious Methodists. - Racer Ex

  23. #23
    Senior Member Road Fan's Avatar
    Join Date
    Apr 2005
    Location
    Ann Arbor, MI
    My Bikes
    Terraferma 650b, Mondonico SL and ELOS, Masi Gran Criterium, Trek 610, Breezer Liberty, Georgena Terry Classic
    Posts
    11,212
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Ok, maybe "noodly" is a stretch for the Golden Gate Bridge, but metallurgy of steels has been verified experimentally in the field and in the lab thousands of times for over the past 100 or more years. It's not new science, and it's not reasonable to treat it as such. It is important to realize that its not always trivial even for mechanical engineers to apply it to real-world problems.

    It is reasonable to look for explanations for what you've experienced. I doubt that anyone intended to say you did not experience what you have. I have not experienced that as a degradation over time, but I'm not as strong a cyclist as you are, I think. I do have a frame that flexes and ghost shifts, but I think there are explanations for both phenomena that do not require my frame to be fatigueing. It gets worse toward teh end of summer, when I'm getting stronger each year.

    Tony Oliver, in his real good book "Touring Bikes" talks about how he likes to orient conventional Columbus and 531 dB tube sets to maximize BB stiffness, minimizing ghost shifting and BB flex. In general he wants the longest length of unbutted seat tube to be bridging between the front derailleur bracket and the BB shell, and similar for the down tube. A physicist (so he understood metallurgy) and cycling fanatic, he made frames for local (Welsh mountains) club and performance riders, and for some serious competitors, selecting tubesets for each based on their size, weight, planned terrain and usage, and strengths as a cyclist. I think he knew what he was doing. This book is at least as good as Talbot's, but its not a builder's manual, more of a design manual.

  24. #24
    Member
    Join Date
    Aug 2008
    Posts
    28
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I have heard the stories about people that have said there worr out frame till they shifted going up hill. I think that steel fatige is one component of that, but not the sole reason.

  25. #25
    Senior Member DannoXYZ's Avatar
    Join Date
    Jul 2005
    Location
    Saratoga, CA
    Posts
    11,507
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    It's not technically "fatigue" in the metallurgical sense since you never ever really stress a frame close enough to its yield-strength to do work-hardening anyway. I suspect what happens is that the tubing themselves are fine, but you end up with lugs and brass that ends up with microscopic cracks. I've cut apart old steel frames and have found a lot of corrosion in the lugged joint itself where there once was full-contact with brass.

    So yeah, old steel frames do get softer from A LOT of empirical evidence. However, HOW that softness develops is arguable and certainly is not metal "fatigue". "Frame fatigue" is a more accurate way to describe it perhaps.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •