Viewing 16 posts - 81 through 96 (of 96 total)
  • Single pivot vs the rest
  • jameso
    Full Member

    This is the bit I am unable to rationalise in terms of the mechanics. The braking force is a constant, so the torque it exerts on the swingarm is a constant. The braking force will therefore bias the suspension to a more compressed state when braking, but the spring rate will remain the same, so the rear suspension will continue to exhibit the same movement in response to a given force (at that point in its travel) as it would when not braking. It is not as if the effect compresses the suspension so far that you hit the bump stops, nowhere near that, it is a relatively small effect relative to the total travel.

    I don’t doubt what you say about the mechanics, sounds right to me. The swingarm has to rotate relative to the wheel to compress though, and braking tends to fix the wheel position relative to the swingarm (if locked up, which of course causes skipping) but it seems that any amount of braking will create some resistance to the natural movement between the two. How much resistance isn’t a Q I could answer though.

    chiefgrooveguru
    Full Member

    “The braking force is a constant, so the torque it exerts on the swingarm is a constant.”

    I’m not sure braking force is ever constant, not for more than fractions of seconds. Is what’s actually happening not more like applying a rotational friction damper to one of the parts of suspension that needs to rotate for the suspension to move, so although the spring rate isn’t changing, a load of compression and rebound damping is being added?

    greyspoke
    Free Member

    Well I guess we disagree on that. The thing about friction (which is why friction damping is pants), is that for a given contact force (fluid pressure) it varies little with speed until the speed gets very low (incipient lock-up). So the small changes in brake disc speed (relative to the caliper) as the suspension moves over bumps and the linkage does its thing, don’t result in appreciable changes in the force at the caliper. As long as your grip on the lever is constant and the wheel isn’t locking up, braking forces are not locking or damping the suspension in any way, they are just applying a constant offset to it’s position (could be zero, depending on the geometry).

    Over longer timescales braking force will vary as heat builds up and so on, but over the time it takes the suspension to go up and down it will be constant. Unless the wheel starts to lock, when it won’t.

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    scandal42
    Free Member

    Just bought a 2020 orange stage 5 frame direct from Orange (one way to make it cheaper it seem). Can’t wait to see what all the fuss is about!

    Snap!

    received mine yesterday evening and it is seriously nice. An itch I’ve always wanted to scratch.

    Suprised how light it is, think it weighs less than my Bfe even with shock mounted.

    What colour did you get it painted in?

    thols2
    Full Member

    Just try riding some different suspension designs and see how it works in the real world. I’ve found Giant Maestro and Spesh FSR bikes to be noticably better under brakes than single pivots. Not a huge difference, but you can feel the difference.

    chakaping
    Free Member

    I’ve found Giant Maestro and Spesh FSR bikes to be noticably better under brakes than single pivots

    Everything is better under braking TBF.

    Just bought a 2020 orange stage 5 frame direct from Orange

    Did Orange say why they had discontinued the Five and S5 – and if the slab-sided swingarms are gone forever?

    chiefgrooveguru
    Full Member

    “ As long as your grip on the lever is constant and the wheel isn’t locking up”

    We’re talking about MTBs and the rear brake. We brake to control our speed before a corner or other technical feature which requires lower speed, often because the terrain is loose, or rough or steep. The only constant is modulation, often to avoid locking the rear wheel.

    zerocool
    Full Member

    I likeed my Alpine 160 with a coil CCDB. It never gave me any problems pedalling up/on the flat and it absolutely ripped on the way down. But then I also liked the Capra and the Demo and a Kona stinky.

    They all ride a bit different to each other but personally I don’t think that the suspension systems (apart from the odd one) are much better than each other, it just depends what you like to feel, the geometry and the quality of the shock.

    greyspoke
    Free Member

    The only constant is modulation, often to avoid locking the rear wheel.

    I don’t think we flutter the brake lever at the same frequency as suspension moves up and down, or time it precisely with suspension movement so it has an effect. The timescales are different.

    rstephenson
    Free Member

    Anyone give me a quick tutorial on how to quote on here..?! Tech idiot alert..

    Scandal – that was the first thing i noticed when I picked the frame up, how light it felt, certainly a chunk lighter than the fuel ex frame it’s replacing. Ive broke my scales tho so don’t know exact weight. Got mine done in wasabi with orange decals, looks gorgeous. Really dont get this ugly thing people seem to think about them, personally I think it looks ace.

    Chakaping, I asked them that because the 2020 was a substantially revised design from the previous gen and they discontinued it after a year. Hope that doesn’t imply it was a shocker! They said something about pushing the evo and the stage 5 being in a complete redesign.. 🤷‍♀️

    Thought £1600 with a super deluxe ultimate was pretty good..

    thols2
    Full Member

    Anyone give me a quick tutorial on how to quote on here..?! Tech idiot alert..

    Copy and paste the text. Select it, then click on the “B-Quote” button above.

    rstephenson
    Free Member

    Copy and paste the text. Select it, then click on the “B-Quote” button above

    rstephenson
    Free Member

    It worked, cheers!

    rstephenson
    Free Member

    Thought £1600 with a super deluxe ultimate was pretty good..

    I’ll qualify that by saying relative to other extremely expensive things in the extremely expensive hobby of mountain biking. It’s still a lot of dosh.

    chakaping
    Free Member

    Thought £1600 with a super deluxe ultimate was pretty good..

    Yep, good deal, but it doesn’t seem so long ago that was about what they cost anyway.

    I’m sure they have more models in the pipeline, perhaps a 180mm rear travel mullet version of the Patriot?

    scandal42
    Free Member

    Orange have a history of dropping a bike and then bringing them back a couple of years later.

    I’ve spoken to 3 people with 2020 stage 5’s and the reports are glowing.

    The £1600 with that shock and colour of choice is a good deal.

Viewing 16 posts - 81 through 96 (of 96 total)

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