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  1. #1
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    6Pack+Wires=New Toy (Techno-geeks only)

    Howdy,

    Came back from I-Bike and had a package from Paul over at Race Tech on my desk. What was in it? His latest leverage ratio/wheel travel analysis package. Let the fun begin.

    One 6 Pack, a few wires, a few minutes of my time, and voila!

    157mm (6.2") of vertical wheel travel (shock metal to metal) and a 5.7% rising rate over the bulk of the stroke.
    Attached Images Attached Images

  2. #2
    Rolling
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    Cool...sexxay.

    This is like doing it with porn on the tv!

  3. #3
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    Quote Originally Posted by PUSHIND
    157mm (6.2") of vertical wheel travel (shock metal to metal) and a 5.7% rising rate over the bulk of the stroke.
    Awesome! Nice to know I'm getting 6" of actual travel.

    So what does the 6% rising rate over the bulk of the stroke mean (please translate in plain English)? Will this info affect how you tune the shocks from now on?

    Looking at the leverage ratio dot plot, it seems like the ratio actually remains the same throughout the travel; i.e. no statistically significant change. If so doesn't that mean that the leverage rate is linear?
    Last edited by SCUBAPRO; 10-11-2005 at 05:33 PM.
    "The best you've ridden is the best you know" - Paul Thede, Race Tech

  4. #4
    Natl. Champ DH Poser/Hack
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    who ya got runnin that thing? jordi la forge? guessin the box on the down tube holds the dilythium crystals.
    No, I'm NOT back!

  5. #5
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    Darren,
    Does that information suggest that one setup will be better for the 6 pack than another,ie an Air or a Coil, or is 5.7 % not the factor, both air and coil can be tuned to suit.
    Thanks

  6. #6
    FM
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    Yeah, while you're at it, can you explain the whole "regressive travel" thing in regards to running a 2.25" stroke shock on the RFX/6-pack?

  7. #7
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    Quote Originally Posted by FM
    Yeah, while you're at it, can you explain the whole "regressive travel" thing in regards to running a 2.25" stroke shock on the RFX/6-pack?
    BIG ditto. I'd love to know.

    coughcoughcough.avyforxmas.coughcoughcough

  8. #8
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    So what does the 6% rising rate over the bulk of the stroke mean (please translate in plain English)? Will this info affect how you tune the shocks from now on?

    Looking at the leverage ratio dot plot, it seems like the ratio actually remains the same throughout the travel; i.e. no statistically significant change. If so doesn't that mean that the leverage rate is linear?
    It means that the suspension between sample points has a rate change of (+) 6%. This means that the suspension rate rises to help increase bottoming resistance toward the end of the stroke. Higher initial leverage for better small bump compliancy, Lower ending number to help in bottoming control. As for the plot, it shows a plot of the rate rise throughout the entire stroke. Note how the left side of the plot is higher than the right side (Rising Rate), not linear. Lastly, we've yet to tune dampers for the 6 Packs at the consumer level, so there would be no changes.


    who ya got runnin that thing? jordi la forge? guessin the box on the down tube holds the dilythium crystals.
    You may laugh, but I actually had to Google that name to find out what you were talking about!


    Does that information suggest that one setup will be better for the 6 pack than another,ie an Air or a Coil, or is 5.7 % not the factor, both air and coil can be tuned to suit.
    Not necessarily, however I'm a fan of the coil personally.


    Yeah, while you're at it, can you explain the whole "regressive travel" thing in regards to running a 2.25" stroke shock on the RFX/6-pack?
    I'm not familiar with the "regressive" term in regards to suspension? Running a 7.875 x 2.25" stroke on a DHX I'm sure would produce a number of geometry issues, both in suspension and chassis though. It would change the starting and ending angles of the rockers which would alter the leverage ratio significantly as well as change the BB and HA of the frame.

    Darren

  9. #9
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    Quote Originally Posted by PUSHIND

    I'm not familiar with the "regressive" term in regards to suspension?
    Suspension can be regressive, digressive, linear, or progressive.

    Regressive=Amount of force required to compress an inch is increasing as it goes through travel, except for each inch, it's a lesser amount of force. A regressive curve will reach a point at which it begins to become digressive. So to compress one inch might take 400lbs, to compress another inch will take 500lbs, to compress another inch will take 450lbs, if the curve continues it will approach linear, and the start to digress, which will be "falling rate". Some bikes can have a regressive spring curve, and they run out of travel before it gets "linear" or "falling rate".

    Digressive=Amount of force required to compress an inch is less as travel is increased.

    Lastly, the problem with putting a longer stroke shock on many bikes, linkage or otherwise, is that if you could keep increasing the stroke of the shock, maintaining the same eye to eye (or even slightly different) you'd reach a point where the suspension would become a falling-rate, because the eyelet hole of the linkage will eventually start to move away from the eyelet hole of the frame. This means the rate of the suspension is changing past what it was designed with, so, with 6" of travel a certain bike might have a linear or progressive rate, and when you increase travel by increasing the stroke of the shock the suspension starts to get either regressive or digressive, in not as many words it's a good way to screw up your suspension and run into a plethora of other problems.
    Last edited by Jayem; 10-11-2005 at 09:38 PM.
    "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

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  10. #10
    FM
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    Darren, thanks for posting back!

    The "regressive" thing came up here: in regards to pushing a 7.5x2.25" fox vanilla RC for use on a RFX or 6-pack. I was curious about it since I got the push factory race system done on my 7.5x2.25 vanilla RC. With 6" rockers, this produces an extra 3/4" of travel, compared to the stock 7.5x2.0" shock. I'm asking about it here, because I was curious why Bulldog and I got different stories about your willingness to service the 7.5x2.25 vanilla. Perhaps this was all a miscommunication.

    A bunch of us with RFX's have played with this and found that a few diferrent rocker designs were produced for the RFX, some have tire clearance issues with the 7.5x2.25 shocks and others don't. yeah, we have kind of a shock cult going on.

    For the record, my set-up works great. Plenty of tire clearance with michelin DH 2.5's, the shock does not bob, or bottom out on flat landings. It's seen moab, whistler and plenty of north vancouver this year on top of the local seattle rides, so I've put it through the paces. If anything, I think it could benefit from slightly less compression damping. I do much prefer the pushed 2.25" RC to the other shocks I have had on this bike (fox RP3 and romic). Not to mention, I really appreciated the time you and Jimmy spent with me on the phone. Good stuff!



    Quote Originally Posted by PUSHIND
    I'm not familiar with the "regressive" term in regards to suspension? Running a 7.875 x 2.25" stroke on a DHX I'm sure would produce a number of geometry issues, both in suspension and chassis though.

  11. #11
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    Regressive=Amount of force required to compress an inch is increasing as it goes through travel, except for each inch, it's a lesser amount of force
    ?? uh...okay

    All I know is that I've been involved in suspension design and engineering for more than 10 years proffesionally now, and neither myself nor my colleagues have ever used that term.

    Suspension systems can be Falling, Rising, or Linear. Damping curves can be Linear, Digressive, or Progressive.

    Suspension design:
    Falling = Leverage increases as the suspension compresses
    Rising = Leverage decreases as the suspension compresses
    Linear = Leverage maintains a constant value as the suspension compresses

    Damping curves:
    Linear = Damping force increases proportionate to velocity
    Digressive = Aggressive initial damping values followed by a sharp leveling where damping value remains the same no matter how much the velocity is increased.
    Progressive = Damping curve where force increases are disproportionate to velocity.

    This remains true whether Motorsport or bicycle.

    Darren

  12. #12
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    Oh yeah

    FM,

    Now it's clear. As for the RFX thing, we had/have some conflicting results/data that prevent us from moving forward with that setup. As for your bike, or others that we've set up in the past, we'll still continue to offer service/support.

    Again, it's just not an application that we feel comfortable releasing. It's a great application for an Avalanche unit though.

    Thanks,

    Darren

  13. #13
    FM
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    Awesome, thats exactly the short of clarification I was hoping for.

    So basically, no problems pulling extra travel out of the RFX using a 2.25" stroke shock, but the old vanilla RC may not be the best candidate due to it's design limitations. (i'm guessing lack of oil volume, etc) Makes me think: perhaps this is why fox quit making this weird size to begin with!

    I think it's awesome when the people behind the products (like yourself or Dave Turner) hop on the boards here to clear stuff like the up in person- thanks again.

    Quote Originally Posted by PUSHIND
    Again, it's just not an application that we feel comfortable releasing. It's a great application for an Avalanche unit though.

    Thanks,

    Darren

  14. #14
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    I'm wearing new socks!!!

  15. #15
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    Quote Originally Posted by PUSHIND
    ?? uh...okay

    All I know is that I've been involved in suspension design and engineering for more than 10 years proffesionally now, and neither myself nor my colleagues have ever used that term.
    ...
    It's ok Darren, some homers might have the word "regressive" in their head since Dave dropped the bomb on them....besides, maybe they got lost in your linear regression fit on that data.

  16. #16
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    Quote Originally Posted by PUSHIND
    ?? uh...okay

    All I know is that I've been involved in suspension design and engineering for more than 10 years proffesionally now, and neither myself nor my colleagues have ever used that term.

    Suspension systems can be Falling, Rising, or Linear. Damping curves can be Linear, Digressive, or Progressive.

    Suspension design:
    Falling = Leverage increases as the suspension compresses
    Rising = Leverage decreases as the suspension compresses
    Linear = Leverage maintains a constant value as the suspension compresses

    Damping curves:
    Linear = Damping force increases proportionate to velocity
    Digressive = Aggressive initial damping values followed by a sharp leveling where damping value remains the same no matter how much the velocity is increased.
    Progressive = Damping curve where force increases are disproportionate to velocity.

    This remains true whether Motorsport or bicycle.

    Darren
    How would you describe each of these then?

    One the first one, it goes from ~linear to falling rate.

    The second one is linear, the amount of force to compress an additional inch is always the same.

    On the third one the amount of force to compress an inch is increasing with travel, but the rate at which it is increasing is actually decreasing. This is key to describing what we are talking about. If you don't believe there are bikes that share this trait, you need to do some more research.

    The fourth one is progressive, the amount of force required increases with each additional inch.
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    Last edited by Jayem; 10-12-2005 at 10:28 AM.
    "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

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  17. #17
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    Quote Originally Posted by PUSHIND
    ?? uh...okay

    All I know is that I've been involved in suspension design and engineering for more than 10 years proffesionally now, and neither myself nor my colleagues have ever used that term.
    Darren, Jayem has his own terminology for everything, and he seems to trust and rely on a linkage program that he takes as gospel that isn't quite right.

  18. #18
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    What is it?

    This is key to describing what we are talking about
    Who is "we"

    you need to do some more research.
    That's what we do everyday here at PUSH. That's why this whole post exists. There is an astronomical amount of time, money and energy being put into this equipment and we take what we do very seriously.

    At this point I feel like your comments aren't meant to be constructive, but rather to attack either myself or my company. In your post you don't provide the information to whether your lines are for leverage rates or damping curves, in either case your infromation describing them is incorrect.

    I would be curious as to your profession, but it appears that you work in the industry?

    Darren

  19. #19
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    Hey Darren,
    Can I get some of those cool PUSH stickers for my car?

  20. #20
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    Do you have any experience with the new Cane Creek Double Barrel shock? http://www.canecreek.com/46.html

    Interested to see how this shock performs on a 6-Pack.

    Quote Originally Posted by PUSHIND
    FM,

    Now it's clear. As for the RFX thing, we had/have some conflicting results/data that prevent us from moving forward with that setup. As for your bike, or others that we've set up in the past, we'll still continue to offer service/support.

    Again, it's just not an application that we feel comfortable releasing. It's a great application for an Avalanche unit though.

    Thanks,

    Darren
    I didn't just drink the koolaid, I stuck my head in the punchbowl.

  21. #21
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    Decals

    sumguy1,

    Drop an e-mail to christina@pushindustries.com. Get her a name and mailing address and she'd be happy to get you setup. We have a new decal sheet that has like 25 different pieces on it.

    Darren

  22. #22
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    Quote Originally Posted by PUSHIND
    I would be curious as to your profession, but it appears that you work in the industry?

    Darren
    Doesn't being a 28 year old bike shop owner qualify one as a suspension specialist?

  23. #23
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    Do you have any experience with the new Cane Creek Double Barrel shock
    No but I did have it's big brother, the Ohlins TTX40 in for an application last year. I have huge respect for Ohlins, but have no experience with the Cane Creek unit. It doesn't seem like there are many out there.

    Darren

  24. #24
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    Thanks for posting. Neat stuff.

  25. #25
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    Quote Originally Posted by Jayem
    H
    On the third one the amount of force to compress an inch is increasing with travel, but the rate at which it is increasing is actually decreasing. This is key to describing what we are talking about. If you don't believe there are bikes that share this trait, you need to do some more research.

    .
    I think there is an issue here with terminology. Darren probably lumps this under the general term of rising rate since even though it's not linear, it's still rising. Your terminology seems to originate from the regressive tax idea the tax rate decreases as income increases. I suppose you can use this terminology here but is it really used in the industry?

  26. #26
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    Quote Originally Posted by lidarman
    I suppose you can use this terminology here but is it really used in the industry?
    The real question is, will it feel the same or different, because if there's a difference in how it works and feels, that's probably enough justification to call it something different.

    It also is very important because you can see that after a while, it becomes linear, and then starts as a falling rate, so this is visually showing people that if they keep increasing the travel of their bike (like by putting a longer stroke shock on) it will become a falling rate.
    "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

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  27. #27
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    Quote Originally Posted by PUSHIND
    your post you don't provide the information to whether your lines are for leverage rates or damping curves
    I know. Originally I was talking about leverage rates. I never brought up damping curves. You brought up damping curves. I've been talking about the same thing.
    "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.

  28. #28
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    Quote Originally Posted by PUSHIND
    It means that the suspension between sample points has a rate change of (+) 6%. This means that the suspension rate rises to help increase bottoming resistance toward the end of the stroke.

    Lastly, we've yet to tune dampers for the 6 Packs at the consumer level, so there would be no changes.
    Darren,

    Thank you for your response and clarification. The plot makes more sense to me now.

    So if you do a regression statistical analysis on the scatter/dot plot (leverage ratio curve) above then you may show a slight decrease in leverage ratio over the bulk of the stroke. How is the % Rise in Rate calculated? Surely, there must be some kind of statistical model used in the calculation or is it based on random points on the plot?

    I also see a wavelike pattern in the scatter plot; is that normal? Does the leverage ratio cycle through the stroke?

    Quote Originally Posted by PUSHIND
    Higher initial leverage for better small bump compliancy, Lower ending number to help in bottoming control. As for the plot, it shows a plot of the rate rise throughout the entire stroke. Note how the left side of the plot is higher than the right side (Rising Rate), not linear.
    In that case, we really don’t need much bottom-out control on the shock, then. Am I interpreting this correctly? If so, then a PUSH'd Vanilla RC or an Avalance will work just as well as the DHX on the Pack. Your thoughts?

    Quote Originally Posted by PUSHIND
    Lastly, we've yet to tune dampers for the 6 Packs at the consumer level, so there would be no changes.
    Oh, I thought you already were; my bad!
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  29. #29
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    Quote Originally Posted by kidwoo
    Thanks for posting. Neat stuff.
    ditto..thanks Darren!!

  30. #30
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    Bring it on, baby...!!!

    Quote Originally Posted by PUSHIND
    Who is "we"


    That's what we do everyday here at PUSH. That's why this whole post exists. There is an astronomical amount of time, money and energy being put into this equipment and we take what we do very seriously.

    At this point I feel like your comments aren't meant to be constructive, but rather to attack either myself or my company. In your post you don't provide the information to whether your lines are for leverage rates or damping curves, in either case your infromation describing them is incorrect.

    I would be curious as to your profession, but it appears that you work in the industry?

    Darren
    It looks like Darren is calling Jayem out. I'll pay to watch this. Right now I give Darren the early lead, because (a) he's making a living at doing this so obviously knows more than a thing or two, and (b) he is not hiding behind a secret indentity...got to give a guy credit for putting his personal brand on the line. Let's get ready to rumble....
    Dad is sad.
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  31. #31
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    Quote Originally Posted by Dad Man Walking
    It looks like Darren is calling Jayem out. I'll pay to watch this. Right now I give Darren the early lead, because (a) he's making a living at doing this so obviously knows more than a thing or two, and (b) he is not hiding behind a secret indentity...got to give a guy credit for putting his personal brand on the line. Let's get ready to rumble....
    I think there is simply a communication and a rapport problem here. They both seem to know a thing or two. It's just that Jayem pushed (excuse the pun) on Darren a little in his thread. I see Jayems point it's just he didn't convey it well to Darren perhaps.

  32. #32
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    Quote Originally Posted by Dad Man Walking
    It looks like Darren is calling Jayem out. I'll pay to watch this. Right now I give Darren the early lead, because (a) he's making a living at doing this so obviously knows more than a thing or two, and (b) he is not hiding behind a secret indentity...got to give a guy credit for putting his personal brand on the line. Let's get ready to rumble....
    Who's "hiding" behind a "secret identity"?, are you trying to get people to post their home address and number?? Makes no sense. What's your home address and phone number?

    Darren hasn't come back and explained if what I showed was in fact what I claimed it to be, he's danced on the issue a bit, but I've posted the progression-charts to show exactly what I was talking about, and I described it in words. What more could one ask? Either it would feel different and it would play a role, or it wouldn't, and we are looking to get some input on this subject. The regressive "rate" will become linear, and eventually become falling rate, which is very much along the lines of what was originally said about using a longer stroke shock on the a particular bike, because you'll loose the progressive travel at the end of the travel. There's a decent amount of bikes out there that have spring curve #3 (diagram), most of them use a progressive shock though, but again, maybe it plays a role and maybe it doesn't, maybe if you put a longer stroke shock on there you could make up for the change in rate at the end of travel with a progressive shock.
    "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

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  33. #33
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    Quote Originally Posted by Jayem
    Who's "hiding" behind a "secret identity"?, are you trying to get people to post their home address and number?? Makes no sense. What's your home address and phone number?

    Darren hasn't come back and explained if what I showed was in fact what I claimed it to be, he's danced on the issue a bit, but I've posted the progression-charts to show exactly what I was talking about, and I described it in words. What more could one ask? Either it would feel different and it would play a role, or it wouldn't, and we are looking to get some input on this subject. The regressive "rate" will become linear, and eventually become falling rate, which is very much along the lines of what was originally said about using a longer stroke shock on the a particular bike, because you'll loose the progressive travel at the end of the travel. There's a decent amount of bikes out there that have spring curve #3 (diagram), most of them use a progressive shock though, but again, maybe it plays a role and maybe it doesn't, maybe if you put a longer stroke shock on there you could make up for the change in rate at the end of travel with a progressive shock.

    I have a question or three.
    Where are you getting these rate charts?
    What reference are you using that regression is defined?
    What bikes have this "spring diag. #3" spring curve and where did you come by this information?

  34. #34
    FM
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    Quote Originally Posted by Jayem
    Who's "hiding" behind a "secret identity"?
    I am.....

    FM, the STAR FANGLED NUT MANGLER!!!!!!

  35. #35
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    Quote Originally Posted by mtn hack
    I have a question or three.
    Where are you getting these rate charts?
    What reference are you using that regression is defined?
    What bikes have this "spring diag. #3" spring curve and where did you come by this information?
    The rate charts are samples, typical of what is found when you measure the rate of many bikes, in this case, they come from the linkage program that maps out the rates of different bikes.

    Reference for digression? Just the fact that the rate of increase is decreasing, and eventually it becomes linear, and eventually falling (if you were to continue the line).

    Many bikes have "spring curve #3", Iron Horse MIII hollowpoint, kona stinky, ventana X-5, specialized enduro, RM ETS...These are just a few, a few that I happen to have in my linkage program, and I haven't gone through all the bikes and catagorized them in this respect(so if I sit here for an hour I could tell you a lot more of them). This sample cross-section of bikes shares this trait to varying degrees, on some it's pretty extreme, and on others it's slight. There's quite a few bikes out there with this tendancy, as there are also a lot of falling rate and rising rate bikes, not too many linear ones though on all the bikes that I've mapped out.
    "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.

  36. #36
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    Quote Originally Posted by FM
    I am.....
    FM = fangled mangler

    actually that has a nice ring to it!

  37. #37
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    Darren,

    Your choice of eyewear for the "Mountain Biking" spread was questionable at best. What was your thought process?

    Thanks

  38. #38
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    Quote Originally Posted by Jayem
    The rate charts are samples, typical of what is found when you measure the rate of many bikes, in this case, they come from the linkage program that maps out the rates of different bikes.

    Reference for digression? Just the fact that the rate of increase is decreasing, and eventually it becomes linear, and eventually falling (if you were to continue the line).

    Many bikes have "spring curve #3", Iron Horse MIII hollowpoint, kona stinky, ventana X-5, specialized enduro, RM ETS...These are just a few, a few that I happen to have in my linkage program, and I haven't gone through all the bikes and catagorized them in this respect(so if I sit here for an hour I could tell you a lot more of them). This sample cross-section of bikes shares this trait to varying degrees, on some it's pretty extreme, and on others it's slight. There's quite a few bikes out there with this tendancy, as there are also a lot of falling rate and rising rate bikes, not too many linear ones though on all the bikes that I've mapped out.
    Not DIgression, REgression.

  39. #39
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    Quote Originally Posted by mtn hack
    Not DIgression, REgression.
    that;s what i was talking about, just didn't take the time to make sure i was using the right word....

    confusing eh?
    "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

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  40. #40
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    Quote Originally Posted by Jayem
    that;s what i was talking about, just didn't take the time to make sure i was using the right word....

    confusing eh?
    No. What I asked was in what reference is this defined?

    I get this
    Quote Originally Posted by Jayem
    Just the fact that the rate of increase is decreasing, and eventually it becomes linear, and eventually falling
    I just wanted to know where you came up with this being a definition for regression.
    edit: or more specifically, regressive rate.

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    Honestly, who cares?

    Darren came here with goodwill to show us what he's been up to and he gets interrogated on what he knows. Darren doesn't have to prove himself, especially since his products have proven themselves many times over.

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    Quote Originally Posted by mtn hack
    No. What I asked was in what reference is this defined?

    I get this

    I just wanted to know where you came up with this being a definition for regression.
    edit: or more specifically, regressive rate.
    Main Entry: re·gres·sive
    Pronunciation: ri-'gre-siv
    Function: adjective
    : decreasing in rate as the base increases
    "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

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  43. #43
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    Quote Originally Posted by Jayem
    Who's "hiding" behind a "secret identity"?, are you trying to get people to post their home address and number?? Makes no sense. What's your home address and phone number?
    Nothing personal, man...just dicking around when I should have been working. I do hide behind my secret identity, and I probably don't have as many super powers as FM does.

    I do appreciate the technical aspects of your points, by the way...in my humble way of looking at it, you are trying to differentiate suspension travel based on the second derivative of the actual travel plot..."yes, it is increasing, but is it increasing at an increasing or decreasing rate..."

    The question I personally have about all of this is one of relevance (not trying to slam anyone here, just pose an open question). The analysis of suspension rates, axle travel, instant center location, blah blah blah whatever, might be interesting on paper, but the real test is how they work and feel when we ride. One design might be 20% more efficient in some aspect than some other design, but if that difference is occuring at a time when some other factor is operating at input levels that are orders of magnitude higher, how much does it really matter? Not to beat a dead horse (but I will), maybe the TNT designs have a brake caliper location that theoretically causes some jack, or squat, or who the heck knows what, impacting suspension motion. But if that negative factor is occuring with a value of X, and the suspension cycling due to inputs from the road at levels of 10X, would we ever really be able to feel the difference? That to me is the real question. We've seen lots of great analysis on paper, but not a lot of it from people who actually design and sell the bikes or suspension bits that we like so much. We test their work on our own butt-o-meters, decide what we like and don't like, and then reverse engineer all sorts of b.s. to convince ourselves why this design is better than the last one we rode.

    I think that is an important point to remember in all of this. It is extremely important for most of us to prove to ourselves and others that this latest, greatest bike or bit we just bought is not only superior on the trail, but on paper as well because otherwise we would be just throwing our hard earned money away on marketing hype. I, for one, am not among the fortunate few whom have the resources (time and money) to ride many different designs and discern meaningful differences between the best of the best. And even if I had the time and resources, I doubt I have the talent level to push any of these rigs to the point where the differences between them would become evident to me.

    This is just one (anonymous, non-super hero) person's opinion. It's about the ride. Talking about it is good, healthy dicking off; arguing about it can also be entertaining. But I will leave it at that. Darren makes his living tuning these systems for racers and consumers alike, and I respect that he lays it on the line every day, even more so when he steps out from behind the secret identity of "PUSH Industries" to talk to us directly. It is smart marketing, but can be risky if you are not straight up, honest, and good at what you do. Others have tried to do what DT, Larry and now Darren have done, and have not been as successful.

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  44. #44
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    Quote Originally Posted by Jerk_Chicken
    Honestly, who cares?

    Darren came here with goodwill to show us what he's been up to and he gets interrogated on what he knows. Darren doesn't have to prove himself, especially since his products have proven themselves many times over.
    LOL! Well Darren obviously cares about all this....and perhaps a lot of us do too (I do). So what is wrong with a little critic? in fact, it's healthy for everyone to argue about this.

    I work in the sciences and this is nothing compared to the challenges brought up by peers in my dicipline! Good science is questioning all assumptions, data, and conclusions. Bad science is taking things at face value and accepting it. When Darren studies suspensions, he is doing science.

    Darren has a lot of experience but if he knew it all, he wouldn't need to study it like he is doing. People in technology can't work in a vacuum (unless you are a vacuum scientist) and need to be open to criticism.

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    stuff

    My eyewear! How dare you question my choice. Actually they're custom from Oakley and include the PUSH Logo laser fired into the lower part of the lens! Take that

    Anyway, much like when you guys get new components and like to show the bling, I get excited with my new toys. That's really the only reason for the post. I've come to know quite a few of you via trail/e-mail/phone, and was just showing what Santa brought early to a community that we at PUSH are feeling a part of.

    The purpose behind the leverage ratio tools, much like the on-board system, is to allow us to better understand suspension characteristics and to be able to apply consistant tuning variables to similar appliactions. As you can imagine, the couple of screenshots that I posted are only a peek into what the software is capable of and, when used in conjunction with on-board DAQ as well as all of the tuning and prototyping capabilities we have, some pretty cool things can happen. We know by riding a Six Pac, Nomad, and SuperMoto that the frames react differently to bumps and rider input, but this lets us better understand the differences.

    Also, We work in an absolute world at PUSH and always like to quantify rider feedback and computer model/simulation. We also understand that theoretical and actual can be very different. Case in point would be these online leverage ratio programs. They provide a nice baseline to go of off, but in reality the actuals don't match the linkage program theoretacals. This can easily be seen by taking our actual 6 Pack data and comparing it to the theoretical linkage software simulation. The numbers don't match. Our numbers come from a tangible bike that you can throw a leg over. Working with real data is what is useful to us.

    So why all of the fuss? Well, because when our customers tell us that they really like something, we want to be able to re-create that product performance for customers with a different application. We want to learn what makes a suspension component perform better than another at the consumer level. 5 Spot owners spoke up and had a lot to say about the new DHX-Air. The RP3 vs. DHX Air debate began. We listened, we tested, and we re-created characteristics that you as riders told us you liked. We can now add that to our database and continue to listen, learn and test. This gear just is another step to making our job easier and more consistent.

    Oh, yeah....and it's really cool.

    Darren

  46. #46
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    Quote Originally Posted by Dad Man Walking
    It's about the ride. Talking about it is good, healthy dicking off; arguing about it can also be entertaining. But I will leave it at that.
    totally agreed, especially after the TNT debacle here. I like nice bike parts and the engineering behind them, don't we all... but it just comes down to the ride for me. Personally I could care less about debating physics, engineering or aesthetics... none of that is going to change the experience of riding a bike.

  47. #47
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    Quote Originally Posted by FM
    totally agreed, especially after the TNT debacle here. I like nice bike parts and the engineering behind them, don't we all... but it just comes down to the ride for me. Personally I could care less about debating physics, engineering or aesthetics... none of that is going to change the experience of riding a bike.
    How wrong you are! Someone, somewhere had to debate physics, engineering and aestherics to create the ride you are enjoying. You might not care, but it happened. They did it and you enjoy it when you ride....You might not care, but you should!

  48. #48
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    Quote Originally Posted by lidarman
    How wrong you are! Someone, somewhere had to debate physics, engineering and aestherics to create the ride you are enjoying. You might not care, but it happened. They did it and you enjoy it when you ride....You might not care, but you should!
    Yeah, but for the most part the guys who do it for real are not the same ones who dick around on these forums debating whether or not an angular moment affects the braking performance when the axle is mounted on the seatsay vs. the chainstay, and/or whether the angle of the rocker negates that moment...and/or...oh crap...my head hurts.

    It's all just dicking around to me...like they say--guys that can do, guys that can't teach, and guys that can't teach dick around on the boards talking about it.

    Not that there's anything wrong with that

    You all should be ashamed of yourselves. Now get out of here and go for a ride.
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  49. #49
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    Quote Originally Posted by lidarman
    Someone, somewhere had to debate physics, engineering and aestherics to create the ride you are enjoying.
    Yes, but that someone also happens to make frames or shocks, which is a different story!

    debating frame/shock design with someone who could make my dream frame/shock: totally worth it.

    debating frame/shock design with someone who, like me, has a non-cycling related desk job: total waste of my time.

    I used to work for a local custom frame shop. If I had a nickel for every letter we recieved from somebody with an interesting, but ultimately worthless design opinion/suggestion, I would still be working in the bike industry.

  50. #50
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    Quote Originally Posted by Jayem
    The rate charts are samples, typical of what is found when you measure the rate of many bikes, in this case, they come from the linkage program that maps out the rates of different bikes.

    .
    A linkage program that is flawed. I have pointed that out to you twice, Jayem, yet you insist you are correct. You are arriving at conclusions based on this program, and are shutting out real world data. That is NOT scientific method. For example, I have posted this picture of an '01 dare that I owned several times here at mtbr, seen here:



    Twice, Jayem posted that the seastay brace would collide with the saddle at the height that the saddle was set. Twice, I replied that no, it would not, I have had the spring off the shock and completely compressed the suspension, and there is no collision. Jayem still insists that he is right, based on the linkage program he is using. What would you believe, a real world test that is pure black and white, or assumptions based on a linkage program downloaded off the internet?
    To quote Darren; " theoretical and actual can be very different. Case in point would be these online leverage ratio programs. They provide a nice baseline to go of off, but in reality the actuals don't match the linkage program theoretacals. This can easily be seen by taking our actual 6 Pack data and comparing it to the theoretical linkage software simulation. The numbers don't match. Our numbers come from a tangible bike that you can throw a leg over. Working with real data is what is useful to us."

    So, who are you going to believe, a professional who who works in the field everyday, and uses multiple means of gathering and processing data and puts that knowledge to work in trial and error tests, or a stubborn amateur making conclusions sometimes from just a photograph?

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