Can a rear tire leak be "dynamic"?

Discussion in 'Trials' started by D2W, Sep 29, 2018.

  1. D2W

    D2W Adventurer

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    Hello,

    The rear tire on my GG - an older Michelin Trials X Lite - occasionally looses its pressure. I normally run at 4.5 PSI. I'm a recreational rider. I just thoroughly submerged the tire in a tub of water and noted no bubbles from the tire nor the valve stem nor the spoke nipples.

    Is it possible for the tire to loose air when it impacts an obstacle (say at the bead)?

    And the tire did come with a "slimey rope" plug in the tread area (i.e., not on the sidewall), but that also does not appear to leak (in the water at least). But perhaps that plug is compromised when the tire is distorted under traction.

    I even increased the pressure to 20 PSI and no bubbles were noted.

    So can a tire leak during its normal operation? Is there a "fix"? My current fix is to simply carry a pump. :)

    And can a vulcanizing patch be applied to the inner carcass as a replacement for the slimey-rope plug?

    Thank you.
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  2. lineaway

    lineaway Long timer

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    Good chance that the plug leaks during every rotation ever so little you will never find it. You can get a new Dunlop 803 GP for less than 80 bucks.
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  3. D2W

    D2W Adventurer

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    Thank you for your thoughts. As a test I mixed up some soapy water and applied it around the plug. Then I took a large screwdriver and used the shaft to apply pressure across the width of the tire. As you predicted ... bubbles and the leak. :)

    So now to buy a new rear tire. FYI here in Canada the Dunlops are $130 and the Michelin X-Lites are $230.
    #3
  4. jonnyc21

    jonnyc21 Trials Ninja

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    Not sure a vulcanizing patch would work as the X Lite's in my opinion don't have a lot of material to work with, but maybe? New tire would be my vote. Good luck.
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  5. 2whlrcr

    2whlrcr gooligan

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    where?
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  6. lineaway

    lineaway Long timer

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  7. 2whlrcr

    2whlrcr gooligan

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    I just ordered one from Motosport and it was a $110. I did have a $20 coupon.
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  8. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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  9. 2whlrcr

    2whlrcr gooligan

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    lol
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  10. lineaway

    lineaway Long timer

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    Flipping a tire is a total waste of time since in the first day you would wear out the `NEW` leading edge and by doing so would cause a drastic change in knob height. Just leave it alone until you buck up for new. Chances are I will wait till January to replace mine. Another two day next weekend, one day in November and I am trialsmaster in December.
    #10
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  11. motobene

    motobene Motoing for 46 years

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    Burst_Cover_GIF_Action_20181001093922.gif I have had two 'dynamic' front tire leaks over 30 years. By dynamic I mean it's fine then either flat overnight or when you hit something hard, like a sharp ledge on a loop trail.

    The first was years ago, and caused by a mesquite tree thorn. A hard hit would pull the thorn fee and psss... flat. Air the tire back up and the thorn would somehow bulls-eye the original hole and seal up from the goop stuff (now Quadboss) that I always have in tires and tubes.

    This last few events same thing again. Tire goes flat for no reason. Yesterday just before section 1 when I punged the front end on a dirt bank horsing around on the the loop. Weird to ride a section on a flat front! Once aired back up and used in normal competition, no leak!

    Then it goes flat after I loaded up. Strange! Don't know why yet.
    #11
  12. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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    Both my '17 and '18 Scorpas have gotten sudden rear tire flats, overnight or by the end of a riding session. Odd in that the tire would hold pressure for weeks, sometimes not changing pressure over multiple days, and the suddenly be flat. I just had the first one my '18, this past week. Both times leaking valve cores..... I went over the tires with soapy water expecting a cut or thorn, but the bubbles came from the valve core. I tried to tighten them and they still leaked. On the '17 I just grabbed an extra valve core from my tire change tool box, and replaced the leaking one. On the '18 I pulled it and decided to lube it instead of replacing it, and that has worked so far.
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  13. motodojo

    motodojo Been here awhile

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  14. broncobowsher

    broncobowsher Long timer

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    I had a truck that had a low pressure leak. Keep it aired to 30+ PSI and it would stay up for months.
    Air down to 20 PSI for a trail ride and it would need air a couple times a day. air it back up and it was fine again.
    Never could find it, got a new set of tires to fix it. Might have been a sidewall leak that only opened up when aired down?
    #14
  15. funmachines

    funmachines Adventurer

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    I used Stan's bicycle tire sealant in my Beta rear tire and it solved the leakage problem I had. It was a lot easier for me to take out the core and inject some goop than to change a tire that had lots of life left. It didn't start working until I rode a bit and the goop got tossed around the inside and stopped the leak.
    #15