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How often should I check tires?

Discussion in 'Gen 2 Prius Main Forum' started by ethanhunt, Jan 8, 2008.

  1. Doc Willie

    Doc Willie Shuttlecraft Commander

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    Yes. Yes. No.

    The ride will be differentm maybe noticable harder. Handling will be different, most likely an improvement. Under inflated tires are squishy and allow the wheels to move from side to side.

    As to hearsay, etc. go do it youself and find out. The results will be obvious pretty quickly, if not immediately. If you want to be sure, make your self a little diving course with varied terrain, road surfaces and speeds. Drive it, pump up tires, drive it again. Have someone else do the same thing with you. Whole project, with two drives will take less than an hour. Then YOU TELL US what the results are.

    You too, can be an expert.
     
  2. jammin012

    jammin012 The man behind The Man

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    Good question.

    As it turns out I work in a facility capable of 30inhg - 10kpsi. If you want to know what steps I took so you can try your hardest to find holes in my plan feel free to read on. Those of you who are satisfied just knowing my tires are full of nitrogen please stop reading now.

    1. I took out the valve stem and allowed the air to escape, then re-inatalled the stem and hooked it up to our vacuum unit. As the vacuum increased I "massaged" the tire until the tread was caved in and vacuum maxed out, 28inhg. Seeing as I'm not at sea level 30" is impossible and yes 28.9 is the max you can get for where I am.

    2. Connected the tire to our tire inflator and proceeded to 50psi. At this point I used my handy dandy AccuPressure tire gage and brought it down to 44psi.

    The nitrogen we use is REQUIRED to be 99.99% dry nitrogen. i.e. 99.99% mitrogen and 99.99% dry. We buy it under contract so no I haven't gone out and tested a sample to make sure. We run it through some very delicate and sensitive intruments and any contamination would be seen immediately... and moisture would be evident during our semi and annual servicing.
     
  3. jammin012

    jammin012 The man behind The Man

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    Good question.

    As it turns out I work in a facility capable of 30inhg - 10kpsi. If you want to know what steps I took so you can try your hardest to find holes in my plan feel free to read on. Those of you who are satisfied just knowing my tires are full of nitrogen please stop reading now.

    1. I took out the valve stem and allowed the air to escape, then re-inatalled the stem and hooked it up to our vacuum unit. As the vacuum increased I "massaged" the tire until the tread was caved in and vacuum maxed out, 28inhg. Seeing as I'm not at sea level 30" is impossible and yes 28.9 is the max you can get for where I am.

    2. Connected the tire to our tire inflator and proceeded to 50psi. At this point I used my handy dandy AccuPressure tire gage and brought it down to 44psi.

    The nitrogen we use is REQUIRED to be 99.99% dry nitrogen. i.e. 99.99% mitrogen and 99.99% dry. We buy it under contract so no I haven't gone out and tested a sample to make sure. We run it through some very delicate and sensitive intruments and any contamination would be seen immediately... and moisture would be evident during our semi and annual servicing.
     
  4. patsparks

    patsparks An Aussie perspective

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    Thanks.
    No I wasn't trying to punch holes in anything I just know the tyre sellers who sell nitrogen just let out the air and fill the tyre from atmospheric pressure with nitrogen which I think would mean there is something like 7% oxygen still in the tyre. You method should get an oxygen content of <0.5% easy.

    Let us know how your testing goes, I still struggle with the whole nitrogen in tyres thing after working in the tyre industry in my youth fitting retreads that showed no sign of oxygen degradation even at the end of their second life but I must admit to not conducting any scientific experiments to test them.

    Something I did notice was if a grain of sand is in the tyre it will be coated in rubber (or whatever the inside of the tyre is coated in) by the end of the tyre's life and form a ball up to 6mm diameter. I suspect one or two grains of sand would do more harm to a tyre than all the oxygen in the tyre.
     
  5. jammin012

    jammin012 The man behind The Man

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    Good call on the sand, hadn't thought of that. Let that be a lesson. When installing new tires MAKE SURE they're clean and free from debris. The wheel also.

    Didn't mean to sound so confrontational before. It just seems to me that any alternative idea to improve your mileage or cost effectiveness of your vehicle gets slammed.
    I'm not worried about getting better gas mileage using nitrogen but if there's a chance my tires will last longer and it doesn't cost anything then what's the downside?
    If you want to monkey around with your car and get 100+mpg more power to you, please let us know how it works out.
    I have to admit I bought one of those magnet things for my XJ6 about 10 years ago and it did nothing to help. $5 thingy, not too upset about it, matter of fact I never thought about it. That doesn't mean the tech doesn't work, just that it isn't cost effective to build a magnet big and powerful enough to actually work.

    Wow this got off topic quick, sorry for that.

    I'll let everyone know how this goes, good, bad or otherwise. Thus far the comment about the ride being rougher is true, but that could be because I'm thinking about it and not much different from before.
     
  6. richard schumacher

    richard schumacher shortbus driver

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    Once upon a time, collapsing the sidewalls of a tire under load in this fashion was a good way to damage them. Are modern tires different?
     
  7. jammin012

    jammin012 The man behind The Man

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    The sidewalls weren't collapsed, last thing I wanted to do was break the bead. No, just the tread that meets the road was caved, looked pretty funky really.