Tubeless spoke tension drop
#26
Senior Member
I recently warrantied one that did the same. The issue is more their valves or rather their retaining nut for the valve. They drill it to allow any air that leaks into the lower chamber of the rim to escape. I have never had or seen this issue with any other rim when using it tubeless. Including the ones we use.
In other words if the lower rim chamber gets pressurized it will blow completely off the rim in the most catastrophic and exciting way.
In other words if the lower rim chamber gets pressurized it will blow completely off the rim in the most catastrophic and exciting way.
#27
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Yes a tubeless tire will exert more rim force than a tire+tube at the same pressure, but for a much simpler reason than the engineer-splaining in that article, above.
Quite simply:
Air pressure always exerts a force perpendicular to its container walls. Remove the inner tube, and:
Q: Why are (some) engineers so bad at explaining things simply?
A: Because they don't adequately understand the problem.
Quite simply:
Air pressure always exerts a force perpendicular to its container walls. Remove the inner tube, and:
- you slightly increase the size of the container
- the total force from air pressure on the container rises
- the air pressure produces more radial inwards force on the rim
- the rim diameter shrinks
- the spoke tension drops
Q: Why are (some) engineers so bad at explaining things simply?
A: Because they don't adequately understand the problem.
But, of course, there are multiple factors at play.
Tire size? 23mm, 25mm, 28mm?
Pressure?
Tube Type?
Is a tube in a tubeless tire the same as a tube in a tube tire?
Brand to brand variability in tire sizes and designs?
What about those riders that pump once to say 110PSI, then ride for a month or so until the pressure has dropped to 80psi?
There are also several recommendations to run tubeless tires at slightly lower pressure than tube type tires.
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#29
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Seems to me the no pinch flat argument is just very convenient and to a large extent FUD to make you believe you cant run normal road tyres at reasonable pressures with out pinch flatting every other ride. I beg to differ. Ive been running 28mm on mixed tarmac/gravel for moths at 50-60 psi, with very little issues.
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I've been trying to come up with something that I'm neither personally nor practically interested in, but about which I can study just enough to shake my fist at it whenever the opportunity presents itself. No luck, so far, though - I just can't get my undies bunched over something that I'm not interested in; I don't know how these guys do it.
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#31
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I don't think that's a benefit, just a peculiarity of tubeless.
A low-pressure tubeless benefit is the ability to use a very low pressure without the fear of pinch flats.
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Lots of variables to look at if you want, but the only things that affect the compression of the rim (the subject of this thread) is air pressure and interior volume of the tire and tube (if there is one) when inflated on the rim.
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#33
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As I explained above, since the interior volume of a tubeless tire is greater than an equivalent tire+tube, the tubeless tire needs to be at a lower pressure to have the same ride character.
I don't think that's a benefit, just a peculiarity of tubeless.
A low-pressure tubeless benefit is the ability to use a very low pressure without the fear of pinch flats.
I don't think that's a benefit, just a peculiarity of tubeless.
A low-pressure tubeless benefit is the ability to use a very low pressure without the fear of pinch flats.