Air travel and hydraulic brakes?

lvquestpaddler
lvquestpaddler Posts: 416
edited August 2018 in MTB general
Hi,

Taking my trusty old GT Avalanche for a one way trip to Tenerife on Friday, but was wondering about the brakes and whether they'd end up with air in the system on a long journey. The back wheel is in position and the front cable tied to the frame to keep the disc central and a shimano spacer between the pads. But could I tape the levers to the bars to keep pressure in the system which would then be closed or is this unnecessary ? Generally I've not had issues before and the brakes firm up if it's been upside down after a few pumps of the lever? Or would the altitude affect any pressure (not much compared to a tyre I suppose)

Just don't want to arrive and find spongy useless brakes!! :shock: :shock: :shock:

Comments

  • cooldad
    cooldad Posts: 32,599
    edited August 2018
    It's a closed system, so no air should get into the brakes unless they are borked. In any event the pressure in the hold is lower than ground level, so if anything they should self bleed.
    But they won't.
    If there is air it will expand, but compress again on landing. But it shouldn't be there in the first place.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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  • cooldad
    cooldad Posts: 32,599
    Last time I flew with a bike they made me deflate the tyres. I also let the air out of fork and shocks, just in case.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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  • lvquestpaddler
    lvquestpaddler Posts: 416
    Ok, cheers for that Cooldad- I've deflated the tyres because the headset was poking above the box slightly so letting almost all the air out has reduced the height overall and I can still add a bit of protective padding. The brakes were bled recently and tbh I haven't had any issues so it'll probably be fine....
  • The Rookie
    The Rookie Posts: 27,812
    cooldad wrote:
    Last time I flew with a bike they made me deflate the tyres. I also let the air out of fork and shocks, just in case.
    Yeah because increasing the gauge pressure of the tyres and suspension by 2-3psi is going to make them really dangerous......
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • fenix
    fenix Posts: 5,437
    It's bollox about the need to reduce air pressure in tyres but pointless arguing with them.

    Don't try and take co2 cartridges either. Use a hand pump.
  • cooldad
    cooldad Posts: 32,599
    The Rookie wrote:
    cooldad wrote:
    Last time I flew with a bike they made me deflate the tyres. I also let the air out of fork and shocks, just in case.
    Yeah because increasing the gauge pressure of the tyres and suspension by 2-3psi is going to make them really dangerous......

    They wanted the tyres flatter than a flat thing. No big deal, A couple of minutes pumping on the other end.

    Fork/shock was my choice, but as I would have checked them anyway before riding, again no big deal.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • steve_sordy
    steve_sordy Posts: 2,454
    Even if it was a vacuum inside the aeroplane hold, the internal pressure would only be the equivalent of an increase of 14.7 psi. Which is nothing to worry about at all (unless you are in the habit of pumping your tyres up to the limit embossed on the tyre wall, or your suspension ditto.

    So, yes it's a nonsense! But as also said, not worth arguing about. :roll:

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