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  1. #1
    The Ancient One
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    Verification of true 4-bar superiority?

    With regard to the 4-bar/faux bar controversy, it should be pointed out that when Devinci first released the Banzai, now called the Remix, they said it was the result of their research with an "instrumented bike". This was a bike with all kinds of sensors at various points on the frame and a back pack carried computer.

    They were looking for info on which points were most under stress and would need reinforcement and which points could be made lighter. They were also looking for the ideal pivot placements to produce efficiency.

    What they came up with looks somewhere between an Ellsworth and a Turner. The drop-out pivot is very close to and right ahead of the axle, like an Ellsworth. The rocker arm is shorter and more angled than an Ellsworth--more like a Turner.

    The bike fell within the claims of the ICT patent, which is international, and Devinci licensed ICT from Ellsworth and put on a sticker.

    Presumably, the reason they do not sell the true 4-bar version in the U.S. is that Specialized won't let them. They would have to license from both just as Dave Turner did.
    Last edited by Steve from JH; 10-18-2005 at 02:57 PM.

  2. #2
    Silence and Thunder...
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    Very interesting..

    ...any links to pictures, documentation and/or reviews of all this?
    ...every day sends future to past...

  3. #3
    Elitest thrill junkie
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    Quote Originally Posted by xjbebop
    ...any links to pictures, documentation and/or reviews of all this?
    It was in a lot of mags a few years ago, and the rider had a backpack if it's the one that I'm thinking about, which housed more computers and the such. The bike had all sorts of data sensors on it, it was pretty intensive.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

    You're turning black metallic.

  4. #4
    Rolling
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    Proof is definitely too strong of a word.

    Only math concepts have proofs. The best this does is support that idea via inductive logic.

  5. #5
    FleshwoundGravityResearch
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    Quote Originally Posted by Steve from JH
    With regard to the 4-bar faux bar controversy, it should be pointed out that when Devinci first released the Banzai, now called the Remix, they said it was the result of their research with an "instrumented bike". This was a bike with all kinds of sensors at various points on the frame and a back pack carried computer.

    They were looking for info on which points were most under stress and would need reinforcement and which points could be made lighter. They were also looking for the ideal pivot placements to produce efficiency.

    What they came up with looks somewhere between an Ellsworth and a Turner. The drop-out pivot is very close to and right ahead of the axle, like an Ellsworth. The rocker arm is shorter and more angled than an Ellsworth--more like a Turner.

    The bike fell within the claims of the ICT patent, which is international, and Devinci licensed ICT from Ellsworth and put on a sticker.

    Presumably, the reason they do not sell the true 4-bar version in the U.S. is that Specialized won't let them. They would have to license from both just as Dave Turner did.

    True four-bar ONLY implies that it consists of four bars in the linkage. Horst link is not implied.

    PS. Aren't you tired of trolling yet?

  6. #6
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    curious as to whether the ICT deal is cheaper if they don't sell in the US also.
    How can you be sure it is only the specialized part that's keeping them out?

    time to work up a list of ICT and Specialized compliant bikes.
    Devinci
    Fuji?

  7. #7
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    Raleigh
    Azonic/xtension bikes

  8. #8
    Lay off the Levers
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    Were their tests inclusive of seat stay pivots as well as chainstay pivots? I don't recall reading they tested both kinds however I presume they did since they already had the equipment. That in itself does not state that they found one to be better than the other or by how much. Nor does it account for how much marketing played a role in the decision. We can already see how the preception is affecting the TNT.

    "Proof" is indeed an overstatement. I think riding the two different versions (of either brand) would be more meaningful.
    Faster is better, even when it's not.

  9. #9
    The Ancient One
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    Quote Originally Posted by Bikezilla

    "Proof" is indeed an overstatement. I think riding the two different versions (of either brand) would be more meaningful.
    Well, I did have a question mark after "proof". But Lidarman is right; "verification" would be a better word.

    As for ride impression vs. instrumented testing, I have just the opposite opinion. If you wanted to know what gas mileage a particular car was going to get before you bought it, would you rely on ride impression? I would rather measure how much gas I put in after driving a certain number of miles. Or if lacking an opportunity to do that, I would rather trust the calculations of an engineer who had all the relevant data than trust someone's ride impression.

    Below are pictures of the instrumented bike in action, the Horst/ICT version of the frame, and the seatstay pivot, U.S. version of the frame.
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  10. #10
    The Ancient One
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    Quote Originally Posted by airwreck
    curious as to whether the ICT deal is cheaper if they don't sell in the US also.
    How can you be sure it is only the specialized part that's keeping them out?

    time to work up a list of ICT and Specialized compliant bikes.
    Devinci
    Fuji?
    I'm not sure of much of anything.

  11. #11
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    Quote Originally Posted by Steve from JH
    Well, I did have a question mark after "proof". But Lidarman is right; "verification" would be a better word.

    As for ride impression vs. instrumented testing, I have just the opposite opinion. If you wanted to know what gas mileage a particular car was going to get before you bought it, would you rely on ride impression? I would rather measure how much gas I put in after driving a certain number of miles. Or if lacking an opportunity to do that, I would rather trust the calculations of an engineer who had all the relevant data than trust someone's ride impression.

    Below are pictures of the instrumented bike in action, the Horst/ICT version of the frame, and the seatstay pivot, U.S. version of the frame.
    I myself couldn't tell from that statement which they felt was better or why.

    As for mileage and such. I would figure most people start with the sticker to narrow the field, then verify with some test group like Consumer reports.

    For bikes, I go with what I read as the consensus, then collect feedback from actual ride reviews, preferably from folks here.

    Now if I were to be nit-picky I'd say nothing in the statement indicates what the instrumentation results were (if one was better or by how much) or even if they were directly compared. For all we know they may have only compared different HL pivot locations and then only compared different SS pivot location performances and never put one against the other. That's a reach for sure. But still they didn't state any conclusions. I would suspect since they're selling both they would be reluctant to make such a statement. But I haven't read everything they said. Since they haven't said which was better we don't know how much business, legal and marketing issues influenced their decisions. They could have decided "There are too many SSP bikes out there to compete against, and lots of ppl dig the HL theory so we'll market that kind" and then later found it to be too expensive or legally troublesome to bring to the US in that format and changed to a equivalent SSP

    Anyway the whole point is, riding the two different bikes or reading some direct comparison reviews will be more meaningful than projecting conclusions on unpublished data we haven't seen.

    I'm not saying one is equal or better. I'm just saying I've read some pretty convincing ride based feedback that supports both. Let's not forget, execution has a major role as well.

    A reverse argument could be made that Jamis went from HL to SSP so they must have found them to be better. I wouldn't make that argument though.
    Last edited by Bikezilla; 10-18-2005 at 03:36 PM.
    Faster is better, even when it's not.

  12. #12
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    Quote Originally Posted by Steve from JH
    I'm not sure of much of anything.
    yea, I realize that what I am asking will never be made public...

  13. #13
    Silence and Thunder...
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    ""If you wanted to know what gas mileage a particular car was going to get before you bought it, would you rely on ride impression? I would rather measure how much gas I put in after driving a certain number of miles. Or if lacking an opportunity to do that, I would rather trust the calculations of an engineer who had all the relevant data than trust someone's ride impression.""

    How often does the "estimated MPG" on the window sticker match up with owner's 'real world' mileage? Sometimes they are right on, but often the posted mpg is the engineer's best possible case estimates. End results vary at a personal level, just as riding impressions do.
    Someone who drives under the speed limit, never revs the engine over 2K and fills up w/ premium fuel, and rides their bike the same way is going to have different results and impressions than a lot of the rest of us.
    Your statement has merit, but how can there be only one truth?
    ...every day sends future to past...

  14. #14
    The Ancient One
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    To test properly by riding, you'd have to get both versions of either the Turner or Devinci (I don't know of any other brands that are exactly the same except for the rear pivot). You'd have to equip them exactly the same and ride the same course, a pretty long and rough one, over and over, switching bikes. You'd need to measure your time, your over all average pulse rate, and ideally your lactic acid buildup. Oxygen consumption would be too difficult. You could also throw in a subjective impression of how whipped you felt at the end, but you'd have to be careful here of prejudice in favor of one design over the other.

  15. #15
    Roy
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    Isn't the Faux bar a 4-bar?

  16. #16
    No, that's not phonetic
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    Congrats. This thread is another certifiable waste of perfectly good electrons.
    My video techniques can be found in this thread.

  17. #17
    Rolling
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    Quote Originally Posted by Steve from JH
    To test properly by riding, you'd have to get both versions of either the Turner or Devinci (I don't know of any other brands that are exactly the same except for the rear pivot). You'd have to equip them exactly the same and ride the same course, a pretty long and rough one, over and over, switching bikes. You'd need to measure your time, your over all average pulse rate, and ideally your lactic acid buildup. Oxygen consumption would be too difficult. You could also throw in a subjective impression of how whipped you felt at the end, but you'd have to be careful here of prejudice in favor of one design over the other.
    Ah..but this is really interesting. If you are trying to minimize time on a lap, the answer will likely be different than what lap you enjoyed the most. If I wanna race, I will grab the hardtail and beat my body up for the shortest lap time. If I want to have fun, there are a lot of other hidden factors.

    So, given that perception is part of the fun factor, people who buy into the H.L. concept as "better" might have to have a H.L. bike to have a fun time in the end. And the other side is that people who have to have a Turner, will have fun on any turner, even if it's a "y-bike" design.

  18. #18
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    [QUOTE=Bikezilla].

    For bikes, I go with what I read as the consensus, then collect feedback from actual ride reviews, preferably from folks here.

    QUOTE]

    That's a good starting point. My take is that the TNT and the previous suspensions probably are very close in real world riding. In fact, without the placebo effect, one could probably not tell a difference in most cases.
    I truly believe that the HL bike was better, but I doubt I could tell the difference in a double blind test. Unfortunately, I tend to know what I'm riding, so I'll be able to tell the difference (even if there is none, I'll admit).

    Oops. More electrons needlessly spilled.

  19. #19
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    Finally some Proof.
    Thank God.
    We now have proof that somebody from Devinci rode around with a vacumn cleaner hose sticking out of a backpack.
    Now, maybe I can get some sleep.
    SEI Racing

  20. #20
    The Ancient One
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    Quote Originally Posted by tscheezy
    Congrats. This thread is another certifiable waste of perfectly good electrons.
    You're right. I think it would be better to have some pictures of a guy riding a bike off a rock.

  21. #21
    No, that's not phonetic
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    Quote Originally Posted by Steve from JH
    You're right. I think it would be better to have some pictures of a guy riding a bike off a rock.
    Electrons should be so lucky!
    My video techniques can be found in this thread.

  22. #22
    FleshwoundGravityResearch
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    Quote Originally Posted by Steve from JH
    You're right. I think it would be better to have some pictures of a guy riding a bike off a rock.

    At least then we would know that you actually rode a bike.

  23. #23
    No, that's not phonetic
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    Lol. He doesn't even own a camera and has never posted a riding shot. Thanks for all the memories!
    My video techniques can be found in this thread.

  24. #24
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    Does living in Wyoming mean anything in this?

  25. #25
    The Ancient One
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    Quote Originally Posted by tscheezy
    Lol. He doesn't even own a camera and has never posted a riding shot. Thanks for all the memories!
    Every year I say I'm going to get a camera and shoot a picture of my bike at the top of Mt. Anne (a little nondescript mountain near my house) in a solid field of Sego lilies with the Grand Teton way off in the background. But I never do.

    Here's a picture I drew in Paint for visual interest.
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