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  1. #1
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    Max psi for tubeless Mavic Crossmax 29er

    I just starting running my Mavic Crossmax wheels tubeless. I'm running a fully rigid singlespeed, and originally had 30 psi in my front wheel before a race. Somehow, I bottomed out and burped the tire, causing me to flat. I couldn't get any air into the tire, b/c I could not get the sidewall to seal back up. What are you guys running? Perhaps I should be running more pressure, b/c I'm fully rigid. Also, has anybody had a tire blow off from too much pressure?

  2. #2
    MTC rep for LPCPCAC
    Reputation: bankerboy's Avatar
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    I am not advocating this and for the record I run 26" CrossMax tubless rims with 2.35 UST Nevegals.

    I have pressurized them to 60 lbs to get a picky tire to seat. I left it at the pressure for 1 hour without issues. I never rode it that way but it held with no issues.

    When I ride, I use 30-35 lbs. I have only had a problem once when I hit the edge of a square rock in the bottom of a small trench. I pinch flatted the tire and put a beautiful flat spot on the rim.

    Are you using UST specific tires or just adapting a standard rim and tire for tubless use? Sidewall tend to be a bit heavier in a UST tire and help with the burping you encountered. Unfortunately they tend to be heaver and wieght is something a lot of non dh racers don't want to accumulate.
    Apathy will get you exactly what you deserve

  3. #3
    usually cranky
    Reputation: b-kul's Avatar
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    the tire will probably go before the rim. the max psi a tire can take should be printed on the sidewall.

  4. #4
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    Yes, I'm using tubeless specific tires. Kenda Small Block Eights! I'm just afraid of burping again...Idk how that happened. I'm a pretty fluid rider, and I only weight 130 lbs....freaked that it's going to happen again during a race.

  5. #5
    Parking Lot Poser
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    i used to ride my X max SL' @ 30# on my Trance X here in CT, never had an issue & i weigh 160 w/out gear

    my guess is the tire is rated to around 60-65psi, but for a dood who's tipping the scales @ 130 thats obviously a bit high

    try adding 5 psi

    i also wonder if those tires have a low thread count (tpi) may make it a bit more vulnerable

    if all else fails get a dual suspension 29r,..... or get a road bike, those cats love high pressure
    feelin good is good enough

  6. #6
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    The whole point of running tubeless is to be able to go to lower pressures. So either that was just a one-off event or something is wrong with your set up. You should be able to run lower than 30psi without a problem.

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