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  1. #101
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    And your impressions about the bike? the ride? and frame stiffness?

  2. #102
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    Eric seems to like it a lot

    My buddy Eric took it out yesterday. He called the ride nimble and supple. He did bottom the suspension a few times, so it's not dialed in yet. I'll try to get a hold of it for a ride at some point and put it through its paces.

    Sorry for the upside down photo.

  3. #103
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    Now I know what an Australian MTB looks like!

  4. #104
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    I got sick of turning my laptop upside down:



    Looks nice... who's next?

  5. #105
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    Quote Originally Posted by nbwallace View Post
    There are bearings in the lower
    and upper main pivots. Everything else has bolts that act as bushings. I fear for
    the longevity of the pivots.
    Have any pics of these disassembled? That really doesn't good. I'd seriously consider getting a machine shop to turn up some Delrin bushings and custom bolts for you. I really don't see the pivots lasting too long like that and then you'll be looking at worn pivots that will need to be machined round again.

    Also, does front derailleur cable housing anchor into the swingarm? It's hard to tell from the photos, but it almost looks that way.

    It certainly looks nice and I'm glad he's happy with it. I'm personally still in the camp of not willing to be an early adopter.

  6. #106
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    Quote Originally Posted by two-one View Post
    I got sick of turning my laptop upside down:



    Looks nice... who's next?
    Wow , it might grow on me but right now, fugly comes to mind.
    This may be a total waste of time but I can't help but think that you might amount to something someday.

  7. #107
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    Quote Originally Posted by two-one View Post
    I got sick of turning my laptop upside down:



    Looks nice... who's next?
    I like It.
    2014 S-Works Epic WC
    2014 Yeti ARC
    2014 S-Works Crux Disc

  8. #108
    help with the zip please
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    Quote Originally Posted by reydin View Post
    Wow , it might grow on me but right now, fugly comes to mind.
    Don't know that I would say that but I know I'm not sold on that cable routing under the bb area.

  9. #109
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    giant anthem will build lighter than that. I saw a 24lb build on here.

    The anthem frame weighs 5lbs 6oz. including the shock

  10. #110
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    Thanks for fixing the photo

    The medium AC-036 only weighed 2040g without shock. That's about 2270 with, which is still almost one third of a pound lighter than the Giant. I'd think you'd drop a lot more building up the Giant to 24 lbs. I can't tell you what I've spent on the Spider to get it to about 26.2 plus I got a great deal on the frame. Also your bike would then say Giant in about 27 places.

    Eric likes the frame, there is one linkage which needs some kind of washer to keep it from knocking. It's more of an annoyance. If this frame came down to something like $600 it would be a great ride for the money.

    I also think it's a nice looking frame, especially in matte carbon.

  11. #111
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    not busting on you. just saying there are some light anthem builds out there.

    the frame looks great. just wondering about any warranty issues ect.

  12. #112
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    Very cool write and build post- Gracias for posting up the project.

  13. #113
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    Great review and nice setup, thanks!
    Can you provide a picture with the rear tire clearance?
    Thanks

  14. #114
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    Does anyone else sense something fundamentally wrong with such a chainstay mounted rear disc caliper on a FS bike? From an observational point of view, that's asking for brake jack, since the caliper is clamping the rotor as it's making a downward motion, which would create a force that would also drive the swingarm downward, stiffening the suspension under braking. The typical caliper location creates a force that is up-forward (a little pro brake-squat) at sag and less up and more forward as you get deeper in travel (more brake neutral).

  15. #115
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    Quote Originally Posted by Varaxis View Post
    Does anyone else sense something fundamentally wrong with such a chainstay mounted rear disc caliper on a FS bike? From an observational point of view, that's asking for brake jack, since the caliper is clamping the rotor as it's making a downward motion, which would create a force that would also drive the swingarm downward, stiffening the suspension under braking. The typical caliper location creates a force that is up-forward (a little pro brake-squat) at sag and less up and more forward as you get deeper in travel (more brake neutral).
    Aside from there being no consensus on what is good and what isn't, this isn't functionally different than many single pivot designs, it's just odd for a design that has a pivot on the "seatstay". Simple swingarm designs are like this.

  16. #116
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    Quote Originally Posted by craigsj View Post
    Aside from there being no consensus on what is good and what isn't, this isn't functionally different than many single pivot designs, it's just odd for a design that has a pivot on the "seatstay". Simple swingarm designs are like this.


    I'm criticizing the location of the rear disc brake caliper. It doesn't really matter what suspension design it is, except for a few designs that have lots of rearward travel/axle path. They're all designed to go up, and that brake is directing forces downward. That's the dreaded brake jack that most bikes have been dreading before the days disc brakes became popular.


    Niner CVA - the caliper catches the rotor when it is moving forward, which has minimal effect on suspension action. Not sure how CVA looks fully compressed, but considering the relatively vertical axle path of CVA suspension design, I doubt its braking characteristics change much according to where it is in its travel.


    Trek ABP - the caliper catches the rotor when it is moving forward, and a little up, having a very slight effect on suspension action, actually make it feel plusher due to the slight brake squat. Due to the arcing axle path, and how the seatstay tilts a little further in its travel range, it becomes more neutral with less braking squat as you get deeper in travel.


    Zerode G1 - Here's a bike known to have brake jack. The brake is mounted on the primary swingarm, which is the main arm that goes from the main pivot to the axle. The braking forces pushes forward, while the swingarm wants to arc backwards and upwards. As it gets deeper in travel, the braking forces want to push down and forward, countering the forces that bumps have on the suspension. This is why such high pivot designs typically have floating brakes. See YouTube video clip of how its braking habits change significantly as it goes through its travel and why similar bikes have floating brakes. Australians making things backwards... Sorry, just teasing.


    Devinci Wilson - proper disc caliper mounting location for isolating braking forces on high single pivot. The swingarm is not always the chainstay, as seen on the two high single pivots above. Note how the mount comes out to position the brake caliper into a position that catches the rotor during the forward moving part of its rotation for relatively* neutral braking (* still counters the rearward travel/axle path).


    Santa Cruz Bullit - Santa Cruz had very limited space to fit this caliper location in, but they put it in a very good spot, before going with a floating brake mount.


    Another faux bar. Hoping that people see the pattern.


    Fabien Barel's Kona that he won the DH World Champs on. He specifically asked for more brake squat, which is why the floating brake is configured that way--it catches rotor so it has more upward force, which apply forces that would try to compress the suspension or lift the axle. Since this pivot arcs back at first, maybe that was a wise move, as this setup counters that rearward arc even less than a more "neutral braking" setup.

    The chainstay mount works for a hardtail, as it only helps to drive the rear end into the ground more, for extra friction between the ground and wheel. In this single pivot application, it works like anti-squat, extending the swingarm. Taking it further than that, my conclusion is the probably not much more credible than others.

  17. #117
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    Most of the photos you posted aren't "faux bar" like this frame. On a "faux bar", the lower swingarm is where the the caliper needs to be anchored unless the upper linkage shares a pivot with the axle (Trek). Assuming that's where you mount the caliper, it doesn't matter how you orient it. The braking force is going to twist the swingarm in the same direction that the tire is rolling. Mounting the caliper at 12 o'clock or 9 o'clock won't have any impact on how braking compresses the suspension.

  18. #118
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    Quote Originally Posted by Varaxis View Post
    I'm criticizing the location of the rear disc brake caliper. It doesn't really matter what suspension design it is, except for a few designs that have lots of rearward travel/axle path. They're all designed to go up, and that brake is directing forces downward. That's the dreaded brake jack that most bikes have been dreading before the days disc brakes became popular.
    ...
    The chainstay mount works for a hardtail, as it only helps to drive the rear end into the ground more, for extra friction between the ground and wheel. In this single pivot application, it works like anti-squat, extending the swingarm. Taking it further than that, my conclusion is the probably not much more credible than others.
    I agree with your last sentence, the rest is a joke. You understand brake jack like you understand anti-squat,,,much too poorly to be commenting on it.

  19. #119
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    Quote Originally Posted by car_nut View Post
    On a "faux bar", the lower swingarm is where the the caliper needs to be anchored unless the upper linkage shares a pivot with the axle (Trek).
    I thought the main design feature behind split pivot and ABP was not mounting the caliper on the main swingarm, to further isolate braking forces from suspension forces, compared to other single pivots. Who says you *need* to mount it on the "lower" swingarm? Isn't it just because it happens to be a stronger place to put it, for faux bars designs, allowing you to lighten up the seat stays? I'm not saying it should be mounted on the seatstay. It's just the position that looks wrong to me. The designers who mount it between the chainstay and seatstay on hardtails say it improves braking power, but I guess that's more bike industry bullcrap, unless they mean because of greater airflow over the pads. It's in one of the articles about those bikes that I recall reading some comment about how it drives the wheel into the ground for more braking traction.

    Quote Originally Posted by car_nut View Post
    Assuming that's where you mount the caliper, it doesn't matter how you orient it. The braking force is going to twist the swingarm in the same direction that the tire is rolling. Mounting the caliper at 12 o'clock or 9 o'clock won't have any impact on how braking compresses the suspension.
    Do you mind elaborating? Why wouldn't it matter if it's mounted at 12 or at 9 or anywhere else for that matter? If what you say is true, what caused the brake jack of older single pivot/faux bar designs, including designs with rim brakes? I know many confused brake squat with brake jack, but I know some were clear about designs stiffening under braking. Do mind including how your explanation covers designs with floating brakes like the Kona DOPE, Lahar, Bullit, Lawwill, etc.? Also, mind explaining how it works to initiate a nose dive when used in mid-air, if that's relevant?

    I'm assuming I'm asking the right guy, who knows of statics and dynamics.

  20. #120
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    Quote Originally Posted by Varaxis View Post
    The designers who mount it between the chainstay and seatstay on hardtails say it improves braking power, but I guess that's more bike industry bullcrap, unless they mean because of greater airflow over the pads. It's in one of the articles about those bikes that I recall reading some comment about how it drives the wheel into the ground for more braking traction.
    Yes, that would be bullcrap.

    Quote Originally Posted by Varaxis View Post
    Why wouldn't it matter if it's mounted at 12 or at 9 or anywhere else for that matter? If what you say is true, what caused the brake jack of older single pivot/faux bar designs, including designs with rim brakes?
    Mass transfer, the same thing that causes dive in the fork.

    Quote Originally Posted by Varaxis View Post
    I know many confused brake squat with brake jack, but I know some were clear about designs stiffening under braking.
    Squat and jack are directions, not unique phenomena. The rear suspension naturally jacks under braking. The geometry of the rear suspension + brake will generate a force that resists that jacking tendency (though negative values will amplify it). Designers can choose to control this force using a floating brake or they can mount the caliper on the swing arm and let the force be determined by the main pivot. The orientation of the caliper is not what matters.

    There is no agreement on the right amount of brake anti-jack as there is with anti-squat. Anti-jack works by unweighting the wheel so benefits come with liabilities.

  21. #121
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    I've got a good experiment. Flip your bike over, spin the wheel and then grab it with your hand. It will apply a force in the same direction of the wheel rotation, regardless of where you grab on the wheel.

    Suspension designs come into play in the direction of wheel rotation while braking. Where the caliper is located is not as important as the design of the suspension itself.

    For hardtails, placing the caliper on the chainstay was popular because the chainstays are usually stronger and don't always require frame reinforcement. I prefer seatstay mounted for convenience.

  22. #122
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    Quote Originally Posted by Varaxis View Post
    I thought the main design feature behind split pivot and ABP was not mounting the caliper on the main swingarm, to further isolate braking forces from suspension forces, compared to other single pivots. Who says you *need* to mount it on the "lower" swingarm?
    Sorry, I don't think I was clear with that. My point was that the caliper needs to be mounted to the same arm that is carrying the axle mount. The reason is so that the caliper isn't moving relative to the disc as you compress the suspension. The Trek ABP is unique in that they place the linkage pivot at the same point as the axle. This gives you the freedom to mount the caliper to either linkage arm. You are correct in stating that the whole point behind ABP is to isolate the braking force from acting on the suspension.

    Quote Originally Posted by Varaxis View Post
    Do you mind elaborating? Why wouldn't it matter if it's mounted at 12 or at 9 or anywhere else for that matter? If what you say is true, what caused the brake jack of older single pivot/faux bar designs, including designs with rim brakes? I know many confused brake squat with brake jack, but I know some were clear about designs stiffening under braking.
    The force on the caliper causes an equal and opposite reaction at the axle. These cancel out. What's driving the suspension to compress (edit: squat) is that you have the wheel spinning and you are now locking the wheel to the swingarm. This makes the swingarm want to rotate in the same direction as the wheel, which compresses it.

    The design types with a floating caliper and added linkage attempt to separate these forces and drive the resulting force into the frame, not the suspension.
    Last edited by car_nut; 12-22-2011 at 04:40 AM.

  23. #123
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    Hey thanks for the write up and pics.
    I'm the guy that got the ebay $639 price before they raised it to $1100 then pulled the frame all together. Happy estore said that they couldnt ship for 5 to 6 weeks and wanted to refund my money. I said "I'll wait". They wrote back "you are the lucky dog...the price is now $1100!"
    Hope it shows up. I'll post the progress.
    Any news updates on the ride?

  24. #124
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    Yea, I was wrong from the moment I was thinking the force created from braking was a vector instead of a torque. That experiment won't really help if I'm dead set thinking it's a vector, as I could just explain it as a force that follows a tangent line, perpendicular to a line drawn from the center of the wheel to the point where I grabbed the edge of the wheel. That's sort of the definition of a torque though, with the axis in consideration. I could just conveniently ignore the axis, though.

    I realized that soon enough when I had people* raising the bullcrap flag and I bothered to look it up, as it was a simple enough mistake. *specifically car_nut, as craigsj seems to like to ridicule others and argue over semantics more than science. Thanks for the extra explanations though.

    Quote Originally Posted by car_nut View Post
    The design types with a floating caliper and added linkage attempt to separate these forces and drive the resulting force into the frame, not the suspension.
    I guess what I really wanted to know was an in-depth explanation on how the design works on Fabien Barel's floating mount brake, which was designed to induce more brake squat in a controlled manner. I recall a comment saying the brake squat in the rear was intended to balance the bike out with fork dive in consideration. I don't really want to think that is bullcrap. Actually, nevermind, that belongs in another thread.

    It's enough to know that odd caliper location doesn't affect brake jack/anti-squat or squat.
    Last edited by Varaxis; 12-22-2011 at 10:02 PM.

  25. #125
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    Re Varaxis.
    Ah just to clarify, the Zerode is a bike designed in New Zealand, far to complicated for the Aussies

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