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Thread: PSI Question.

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    Dazzler thiskidgotmoxie's Avatar
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    PSI Question.

    Hi,

    I have a very quick question about about tubular psi: it says on my tyres (Conti Podiums) that the max psi is 180. But, I thought that tubies went much higher, so I asked someone at the track and they told me that tyres can actually go much higher than their stated psi, which is listed deliberately low because of some kind of safety standard or something. Is that correct? Can I safely pump tyres that *say* 180 up to 210?

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    don't go over the rating on the sidewall.

    Move up to the Sonderklasse if you are keen to pump 200+ into your track tyres.

  3. #3
    如果你能讀了這個你講中文 genericbikedude's Avatar
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    I think that the more interesting question is the more general one: since the "true" max pressure ratings for clinchers are consistently underrated for liability reasons, is the same true of tubies?

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    For most purposes on nearly all tracks, 140 psi is plenty for tubulars. Go to 160 psi for occasional solo efforts and you're really big, but you don't need a higher pressure. You'll just start skittering and slipping.

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    dan bones! goldenskeletons's Avatar
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    i've been under the impression that the quality of the track you're riding on will also mandate what pressure you ought to ride around at. Kissena, for instance, is fairly bumpy, and while the tires i have are rated for 160, i'd really like to compare my time on a 1000m at 160 and again at 140 and see if my impression holds true.

    however, this assumes that i ride consistently. ...that's not really the case

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    cxmagazine dot com pitboss's Avatar
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    aren't rim classifications somewhat of a factor in total wheel-accepted PSI?
    Deathlap - cyclocross, training, beer,...escape hatch

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    Quote Originally Posted by pitboss
    aren't rim classifications somewhat of a factor in total wheel-accepted PSI?
    Not for a sew up, the pressure of the tire is minimal against the rim, thats why we have to glue them on! For a clincher, yes, because the beads of the tire push out against the lips of the rim. Too much pressure could cause a failure.
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    Quote Originally Posted by goldenskeletons
    i've been under the impression that the quality of the track you're riding on will also mandate what pressure you ought to ride around at. Kissena, for instance, is fairly bumpy, and while the tires i have are rated for 160, i'd really like to compare my time on a 1000m at 160 and again at 140 and see if my impression holds true.

    however, this assumes that i ride consistently. ...that's not really the case
    Yes, track surface is a factor in determining tire pressure, but only a minor factor. On a really smooth track, for certain special events, you can go up to 180 psi. The kilo comes to mind. But for most use you won't want to ride that kind of pressure, regardless of track surface. On a rough track, you'll never get to pressures that high or you'll be bouncing and skittering all over the track. And in any event where you're steering a lot -- keirin comes to mind -- you don't want to be over-pressured. You may find differences in handling between, say, 140 and 160 psi, but not out to ranges of 180-200 or 120 psi.

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    Quote Originally Posted by 11.4
    You may find differences in handling between, say, 140 and 160 psi, but not out to ranges of 180-200 or 120 psi.
    People here sometimes run 120 cause the track is so rough.

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    Dont go over 120... I learn the lesson years ago... 120 psi is like the ideal in concrete. More than that u r risking a flat, and have flats in the upper bank isnt that funny at all... Well is not so critical the problem is that u can take other prople with you and thats not fair... too much air and too less psi is being asking for a flat. If the track is hot in the summer do not go over 110 because during the race and the heat the preassure in the tire goes up... always consider temperature, climate, and track surface. In a nice track as ADT a wouldnt be afraid of going to 140 psi max.


    Well have fun

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    Senior Member CafeRacer's Avatar
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    140 are you nuts! You tell a 230lbs 6foot 3 sprinter to only inflate his tires to that and youll get laughed at. Id say its more common then anything espessialy for sprinters to go closer to 200 or just over.

  12. #12
    TJ
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    Quote Originally Posted by CafeRacer
    140 are you nuts! You tell a 230lbs 6foot 3 sprinter to only inflate his tires to that and youll get laughed at. Id say its more common then anything espessialy for sprinters to go closer to 200 or just over.

    Any suggestions on where to find a pump capable of over 200 psi. I haven't seen any.
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    spinlikehell mickster's Avatar
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    eg http://www.silcapompe.it/pista_en.htm
    Goes to 200 psi, though it helps to have a friend hold the chuck onto the valve whilst you pump.

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    Rumor has it that tubulars are rated at 50% below their burst pressure. I have never tested this rumor myself.

    FWIW, the rolling resistance curve gets really, really flat by the time you're in the 180 PSI neigborhood. Exceeding that for a smooth board track will probably do no harm, but I kind of doubt you're going to see any difference on the results sheet. Also FWIW, I've never ridden a concrete track smooth enough that anything above about 140 didn't just bounce around like a jumping bean.

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