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  1. Join Date
    Nov 2007
    Posts
    329
    #1
    When inflating tires, do you have to get off the car? para accurate yung pressure?

    Diba if the car has load, mas mabigat, then mas mataas yung pressure ng gulong?

    Parang salbabida, if may nakasakay, mas matigas...

    I think it's the same concept with the tires, but am i missing anything out? Are people actually a significant increase to the car's weight?...

    So am i right that the pressure increases when there are people on the car?

  2. Join Date
    Oct 2002
    Posts
    15,528
    #2
    i dont think its necessary.

  3. Join Date
    Oct 2002
    Posts
    10,820
    #3
    depends on...

    1. the ratio of total passenger weight with the vehicle curb weight. if that ratio is small (you weigh 80 kg, the vehicle weighs 2000 kg) then the effect is negligible.

    2. the tyre. a bigger contact area requires less pressure (F = P x A). so the wider the tyre the less is the effect of passenger weight. also, radials flatten more than non-radials and thus increases the area of contact with the pavement more as more weight is added. as the area of contact increases the required air pressure to counteract the added weight decreases.

  4. Join Date
    Jun 2007
    Posts
    272
    #4
    for me, yes sir, there is a significant increase in pressure when there's a load. And as much as possible, kinin sa an pressure na hindi pa tumakbo iyung auto. Cold air pa rin ang nasa loob, just leave a margin for the pressure when it turns warm/hot temp like on the move.

  5. Join Date
    May 2006
    Posts
    3,722
    #5
    Well for me it's not really necessary if there would be only two of you inside. Little or no difference regardless of tire size.

    Now, if you are fully loaded with passengers then it would be wise to take them off first then fill.

    In the case of heavy cargo loads that you can't unload while you fill, like in the case of pick-up trucks, then it would be advisable to set the pressure less 1 or 2 PSi of the recommended rating to relieve the tire sidewalls of too much pressure.

    My general rule would be to fill or regulate tire pressure BEFORE putting on any load. Works better for me.

    my :twocents:

    .
    Last edited by Memphis Raines; December 30th, 2008 at 02:42 PM.

  6. Join Date
    Oct 2002
    Posts
    9,894
    #6
    not really. unless the car is up on a jack :hihihi:

  7. Join Date
    Sep 2008
    Posts
    641
    #7
    wag na... sayang lamig ng aircon pagnagbukas pinto and isa pa, mainit sa labas!

    for me, if ako lang mag-isa or 2 lang sakay, i/we don't get off anymore. if jampacked, labas car para mas tama pressure..

  8. Join Date
    Jul 2006
    Posts
    3,601
    #8
    The only condition for maintaining tire pressure (checking/adjusting/etc) is when the car has been driven a while. The tires get warm, the air inside gets warm, it expands, increases the tire pressure.

    That's why on a cold tire if it's at 30psi, once you've driven it the pressure can reach up to +4 psi when it gets warmed up, even more on a really fast run. This is why it's recommended to increase tire pressures when driving faster than a certain speed.

    Weight balance is negligible when checking tire pressure. Thing is, just fill it up with more than you need, and adjust it the next morning when the tires are still cold. Instead of, say, 10 seconds worth of air, try 15 or 20 if it doesn't have a gauge.

  9. Join Date
    Nov 2007
    Posts
    329
    #9
    Quote Originally Posted by mbeige View Post
    The only condition for maintaining tire pressure (checking/adjusting/etc) is when the car has been driven a while. The tires get warm, the air inside gets warm, it expands, increases the tire pressure.

    That's why on a cold tire if it's at 30psi, once you've driven it the pressure can reach up to +4 psi when it gets warmed up, even more on a really fast run. This is why it's recommended to increase tire pressures when driving faster than a certain speed.

    Weight balance is negligible when checking tire pressure. Thing is, just fill it up with more than you need, and adjust it the next morning when the tires are still cold. Instead of, say, 10 seconds worth of air, try 15 or 20 if it doesn't have a gauge.

    thats what i do...

  10. Join Date
    Nov 2005
    Posts
    7,970
    #10
    i do get out of the car not to lessen up the load but to inflate it myself it's my habit to check and maintain the tire pressure at the nearest gas station (once a month) with working pressure gauge

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When inflating tires, do you have to get off the car?