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  1. #1
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    Tubleless problem - dualie vrs. hardtail difference?

    Had my first problem yesterday losing air on a tubeless setup in over 4 years of riding multiple wheels/tires. Luckily, had a tube with me and rode out but had to abandon 50 mile race half-way through. Working on bike today, and just wondering one thing before setting the wheel up again. This tire (Spec LK Fast Trak) has been on the rear wheel for 7 or 8 weeks holding air fine with multiple rides. The only change I made was moving the wheel from my hardtail to dual suspension for the event. Ran the same pressure as always which granted is low (<30 psi). The tire was not cut at all, had plenty of sealant left even when I put the tube in. It looked like sealant/air was very slowly escaping from the bead/rim. It's like the tire had a series of small burps losing air instead of a big failure all at once. Has anyone ever heard of a need to run a higher pressure on the rear on your dualie with a tubeless system than a hardtail? Wondering if the up and down motion of the suspension is tougher on the wheel/tire than on a hardtail. Thanks

  2. #2
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
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    Quote Originally Posted by highplaces
    Had my first problem yesterday losing air on a tubeless setup in over 4 years of riding multiple wheels/tires. Luckily, had a tube with me and rode out but had to abandon 50 mile race half-way through. Working on bike today, and just wondering one thing before setting the wheel up again. This tire (Spec LK Fast Trak) has been on the rear wheel for 7 or 8 weeks holding air fine with multiple rides. The only change I made was moving the wheel from my hardtail to dual suspension for the event. Ran the same pressure as always which granted is low (<30 psi). The tire was not cut at all, had plenty of sealant left even when I put the tube in. It looked like sealant/air was very slowly escaping from the bead/rim. It's like the tire had a series of small burps losing air instead of a big failure all at once. Has anyone ever heard of a need to run a higher pressure on the rear on your dualie with a tubeless system than a hardtail? Wondering if the up and down motion of the suspension is tougher on the wheel/tire than on a hardtail. Thanks
    Which rim? Is the tire a tubeless version?

    Why did you have to drop out after installing the tube let you continue?
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  3. #3
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    The wheel/rim is Specialized 29 Roval. It has been a great wheelset for a year or so. The tire is their 2Bliss. Putting the tube in, had planned to keep going even though now out of Hutch FastAir and CO2 already used to keep rolling prior to using mini pump. But.....putting the rear wheel back on for the first time on my new build (second Niner Jet 9) and pulling it up tight into the dropouts, the rotor was so high in the caliper the wheel would not turn! Having never seen such a thing, I played around for a very long time with it. I ended up carefully riding out with the wheel slightly lowered in the dropouts. Looking at this yesterday, I noticed for whatever reason it is very very hard to pull the wheel into the drops. It is like there is barely enough room for the drive side hub to fit and move up tight. My guess is when the LBS built it up a few weeks ago, the wheel was not in correctly hence not enough spacers were installed to move the caliper up high enough.

  4. #4
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    Sounds like perhaps your caliper was adjusted for a prior rotor that is smaller than the one you are now using.

    Also, your first post "implies" that you are using the same wheel but your second post sounds like it is a newly built wheel.
    Nobody cares...........

  5. #5
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    Sorry, confusing information, just looking for advice to avoid trouble in the future. The caliper and all else on the bike is new, except for the wheelset which was just moved over. Standing beside the trail looking at the problem you would think the rotor is too large, but it had worked fine for about 5 or 6 hours of riding before all went south. Heading to shop at end of day for expert advice....thanks. In the future, I will start out with a higher pressure and work my way downwards with this bike. Love tubeless and will not be changing back. 4 years without a flat was a nice winning streak.

  6. #6
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by highplaces
    The wheel/rim is Specialized 29 Roval. It has been a great wheelset for a year or so. The tire is their 2Bliss. Putting the tube in, had planned to keep going even though now out of Hutch FastAir and CO2 already used to keep rolling prior to using mini pump. But.....putting the rear wheel back on for the first time on my new build (second Niner Jet 9) and pulling it up tight into the dropouts, the rotor was so high in the caliper the wheel would not turn! Having never seen such a thing, I played around for a very long time with it. I ended up carefully riding out with the wheel slightly lowered in the dropouts. Looking at this yesterday, I noticed for whatever reason it is very very hard to pull the wheel into the drops. It is like there is barely enough room for the drive side hub to fit and move up tight. My guess is when the LBS built it up a few weeks ago, the wheel was not in correctly hence not enough spacers were installed to move the caliper up high enough.
    The caliper should not require spacers at all. Sounds like you need to have a long talk with your LBS.
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  7. #7
    transmitter~receiver
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    Quote Originally Posted by highplaces
    Sorry, confusing information
    Nah... it's all clear.
    Chas doesn't read threads, he just skims them looking for any mention of non-UST tubeless so he can post a facepalm or moronic one-liner. Hence, he didn't see the part in your second post where you say it's been a great wheelset for a year. I guess it also didn't click that a Specialized Roval 29er wheelset is not something your LBS builds.
    The only thing about a dual suspension bike that would make you burp more is if you are pushing it harder and/or are less choosy about your lines. I don't think it's inherent in the bike, per se.
    You definitely need to have a chat w/your LBS about the build... something sounds fishy.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

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