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S25 frame & air flow

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    S25 frame & air flow


    While I understand that the S25 (and S19) new frames are meant initially for load weight distribution and protection against objects pocking in the back and such, I have been wondering:

    - does it improve air flow?

    - can it be bent to improve air flow in a way that makes sense?

    This is a feature many suspended backpack provides, which is nice. Generally this is done by curving the back of the back a certain way which forces the bag away from your back. Since the Synapse has a foam + net, I suspect this might actually work. But then again, it might not ;-) Anyone tried?


    I found that the Internal Frame does improve air flow but not quite the in same way that you are suggesting.

    The Synapse normally hugs your body very closely by nature of its soft back. With the frame inserted, the Synapse has a smaller contact patch against your spine (but still very comfortable) because the frame is rigid and may add a small air gap or a little bit of air movement. Do note that the bottom of the frame is unsecured inside the pack body, so it cannot be bent in such a way that would encourage the pack to arch off your back, although it will add comfort and support for many users.

    However, the Internal Frames debuted in November, which for most of us is a cold time of year. It is only just starting to get warmer here but I couldn't say how this summer will turn out with a frame installed.


      I can only speak from personal experience, but yes, the frame sheet does appear to improve the airflow to my lower back.
      But the sheet is bent in a way that does that. If I adjusted the sheet, I could probably get rid of or reduce the airflow. I haven't done that though since I mostly use my s25 when it's hot out or while I'm fairly active and would be warm already.


        thanks, that sounds promising enough. I don't expect a suspension-like airflow but a little bit of air would probably be good enough for me.
        I mainly noticed that when I use my hiking 20L-ish bag with a real suspension i don't get sweat at all on my back during my commute (bike) at 15C, but I do with the S25. I prefer the S25 in every other aspect though so I'm commuting with it anyway, and I'll take every little bit of air flow.

        /me goes to order page ;-)