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Flight Junkie
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Discussion Starter · #1 ·
I just mounted up a Mythos tire to the new Stan's Olympic 29er rim. I used the rim strip. Wow! I am impressed how tight it fits. I mounted it up (took tire lever to get it on) and it fits really tight. I followed Stan's recommendation to air it up before putting in the latex goo. It aired up quickly with just the floor pump and held air well. It was really hard to get the bead off the rim again, it took a wet tire lever to do it. I then added the stuff and did all the tricks the website video's said to do. Aired up in less time than a tube would. The tight fit really lends to confidence. I am trying this on the back first so far due to a ripped liner. After having the Dyad rims (with the loose fitting tires and having tubes blow out the sides because of the loose fit) I am happy with how well the tire fits on this rim. I will be trying these out on the trail soon.
 

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Great news!

IBIKEAZ said:
I just mounted up a Mythos tire to the new Stan's Olympic 29er rim. I used the rim strip. Wow! I am impressed how tight it fits. I mounted it up (took tire lever to get it on) and it fits really tight. I followed Stan's recommendation to air it up before putting in the latex goo. It aired up quickly with just the floor pump and held air well. It was really hard to get the bead off the rim again, it took a wet tire lever to do it. I then added the stuff and did all the tricks the website video's said to do. Aired up in less time than a tube would. The tight fit really lends to confidence. I am trying this on the back first so far due to a ripped liner. After having the Dyad rims (with the loose fitting tires and having tubes blow out the sides because of the loose fit) I am happy with how well the tire fits on this rim. I will be trying these out on the trail soon.
Thanks for the write-up. One question. Stan told me that a rim strip is not necessary if you use the "special" spoke tape. Did you consider not using the rim strip?

Smart call trying it on the rear first! That is exactly what I plan on doing :)
 

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Did dave thomas include the valves for the tape only application? I went the tape route using some wire nano's and they filled right up. I'll have more to report once I kick the flu.

e
 

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Flight Junkie
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Discussion Starter · #4 ·
Strips

I went with the rim strips due to the problems people have had with 29er tubless. I decided it would be safer to have a tighter fit. Stan does say that he has had success with just the yellow rim tape, but since all the talk of blowoffs I wanted to be as safe as poss.
 

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Stan's Concerns

I was interested in these rims because of their weight and reputation, but then I went on Stan's site and noticed the Max PSI rating of 42 for all of his rims. This makes me worry about the durability of the rim over year's of riding. Sure, if I'm going to plan on rebuilding the wheelset every year or couple of year's it makes sense. It seems to me though this max 42 psi rating is a result of the rims extrusion shape failing over time if the rim is run at higher pressures. I know not many of us run at pressures over 40, but it just concerns me. I've never seen a max pressure rating on a rim before and their are quite a few sub 400g rims out their for road use. Like Mavic Open Pros, Velocity Razors and Aeroheads. They may be a couple millimeter's narrower, but they don't have a max psi rating.

This makes me think that the durability of this rim over several years isn't good and it makes me worry about running pressures even close to 40, which I do. I usually run higher on the way to the trail, on the road, and then drop pressure at the trail head.

Words?
 

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hispanic mechanic
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I don't know for sure...

JMKM said:
I was interested in these rims because of their weight and reputation, but then I went on Stan's site and noticed the Max PSI rating of 42 for all of his rims. This makes me worry about the durability of the rim over year's of riding. Sure, if I'm going to plan on rebuilding the wheelset every year or couple of year's it makes sense. It seems to me though this max 42 psi rating is a result of the rims extrusion shape failing over time if the rim is run at higher pressures. I know not many of us run at pressures over 40, but it just concerns me. I've never seen a max pressure rating on a rim before and their are quite a few sub 400g rims out their for road use. Like Mavic Open Pros, Velocity Razors and Aeroheads. They may be a couple millimeter's narrower, but they don't have a max psi rating.

This makes me think that the durability of this rim over several years isn't good and it makes me worry about running pressures even close to 40, which I do. I usually run higher on the way to the trail, on the road, and then drop pressure at the trail head.

Words?
But it looks to me like this rim lacks a bead hook. I'm sure this is prolly done to maximize the surface area contact betwixt rim and tire, but it would limit maximum pressure allowed in order to keep the bead on.
Please correct me if I'm wrong.

the los
 

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Non Dual Bliss
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JMKM said:
I was interested in these rims because of their weight and reputation, but then I went on Stan's site and noticed the Max PSI rating of 42 for all of his rims. This makes me worry about the durability of the rim over year's of riding. Sure, if I'm going to plan on rebuilding the wheelset every year or couple of year's it makes sense. It seems to me though this max 42 psi rating is a result of the rims extrusion shape failing over time if the rim is run at higher pressures. I know not many of us run at pressures over 40, but it just concerns me. I've never seen a max pressure rating on a rim before and their are quite a few sub 400g rims out their for road use. Like Mavic Open Pros, Velocity Razors and Aeroheads. They may be a couple millimeter's narrower, but they don't have a max psi rating.

This makes me think that the durability of this rim over several years isn't good and it makes me worry about running pressures even close to 40, which I do. I usually run higher on the way to the trail, on the road, and then drop pressure at the trail head.

Words?
Well, using my ******* math, 40 PSI in a 2" MTB tire puts the same amount of stress on a rim as 160PSI in a 1" (25mm) road tire does. That's buttloads of pressure. I don't know this for fact, but I suspect that Stan's pressure limit for the rims has more to do with safety during bead seating than it does operating pressure.
 

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IBIKEAZ said:
I just mounted up a Mythos tire to the new Stan's Olympic 29er rim. I used the rim strip. Wow! I am impressed how tight it fits. I mounted it up (took tire lever to get it on) and it fits really tight. I followed Stan's recommendation to air it up before putting in the latex goo. It aired up quickly with just the floor pump and held air well. It was really hard to get the bead off the rim again, it took a wet tire lever to do it. I then added the stuff and did all the tricks the website video's said to do. Aired up in less time than a tube would. The tight fit really lends to confidence. I am trying this on the back first so far due to a ripped liner. After having the Dyad rims (with the loose fitting tires and having tubes blow out the sides because of the loose fit) I am happy with how well the tire fits on this rim. I will be trying these out on the trail soon.
Was the Mytho tire a folding one or steel bead?

I mounted a set of steel bead Nano's and had the same great luck. I have put over 300 miles on them and had zero problems. I'm running around 32-35 psi right now with just the yellow rim tape.

I think the reason why Stan doesn't recommend more then 40 psi is due to the tire blowing off the rim. Not because the rim can't handle the pressure.
 

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I'm pretty sure the 42 psi thing is some CYA for Stan because the non-tubeless tires that he advocates using with his rims are very unlikely to blow off at 42 or less. I don't think its a durability issue at all. You could probably run true tubeless tires (if we had them in 29") safely at much higher pressures.
 

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DWF said:
Well, using my ******* math, 40 PSI in a 2" MTB tire puts the same amount of stress on a rim as 160PSI in a 1" (25mm) road tire does. That's buttloads of pressure. I don't know this for fact, but I suspect that Stan's pressure limit for the rims has more to do with safety during bead seating than it does operating pressure.
I agree. Wall tension in a cylindrical or spherical object grows rapidly as the radius increases, something like the third power of the radius (been a while since I cracked a physics book so correct me if I'm a power either way), so 100psi in a 55mm tire puts one heck of a lot more strain on a rim than 150psi in a 23mm tire. Why sould you want to run any more than this a big dirt tire anyway, unless your 275#, and then why would you spend an lot of money for a rim that weighs 3oz less than a much stronger one?
 

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Training in Mexico
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DWF said:
Well, using my ******* math, 40 PSI in a 2" MTB tire puts the same amount of stress on a rim as 160PSI in a 1" (25mm) road tire does. That's buttloads of pressure. I don't know this for fact, but I suspect that Stan's pressure limit for the rims has more to do with safety during bead seating than it does operating pressure.
Sometime my ******* Math works, but in this case the stress in the rim due to pressure is not a function of tire size. The stress in the rim is due to pressure and rim geometry alone irreguardless of tire size.

Stan's 42psi max is a safety factor blow off thing.

EPO
 

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being is
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vocabulary police

EPO said:
Sometime my ******* Math works, but in this case the stress in the rim due to pressure is not a function of tire size. The stress in the rim is due to pressure and rim geometry alone irreguardless of tire size.

Stan's 42psi max is a safety factor blow off thing.

EPO
Not trying to be an A-hole but "irreguardless" is not a word. "Irrespective" and "regardless" are words. I had a boss who said IR all the time but I couldn't correct the boss so I had to jump on this one. Sorry. :rolleyes:
 

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EPO said:
Sometime my ******* Math works, but in this case the stress in the rim due to pressure is not a function of tire size. The stress in the rim is due to pressure and rim geometry alone irreguardless of tire size.

Stan's 42psi max is a safety factor blow off thing.

EPO
Irregardless of what PI says :D , I would have to agree here. If you are talking about the affect of air pressure on the rim, since the rim does not expand or contract like a tire does, the pressure on the rim is the pressure in the tire. The rim doesn't care about the overall volume of air in the tire.
 

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Training in Mexico
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Double Negatives....drats!

pseudo intellectual said:
Not trying to be an A-hole but "irreguardless" is not a word. "Irrespective" and "regardless" are words. I had a boss who said IR all the time but I couldn't correct the boss so I had to jump on this one. Sorry. :rolleyes:
"IIrreguardless" is double negative now that I thing of it....Hope everythings OK with the boss in the fact that you can bring his slack jaw jibbish to light:)

I will use 'irrespective" 5 times today to remember.
I will use it in a sentance now:
Irrespective of the smell that rises from my tabacy spit, I still will keep on spitting in my Dew bottle 'tell she's full.

Thanks as vocab is power,
EPO
 

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JMKM said:
I was interested in these rims because of their weight and reputation, but then I went on Stan's site and noticed the Max PSI rating of 42 for all of his rims. This makes me worry about the durability of the rim over year's of riding. Sure, if I'm going to plan on rebuilding the wheelset every year or couple of year's it makes sense. It seems to me though this max 42 psi rating is a result of the rims extrusion shape failing over time if the rim is run at higher pressures. I know not many of us run at pressures over 40, but it just concerns me. I've never seen a max pressure rating on a rim before and their are quite a few sub 400g rims out their for road use. Like Mavic Open Pros, Velocity Razors and Aeroheads. They may be a couple millimeter's narrower, but they don't have a max psi rating.

This makes me think that the durability of this rim over several years isn't good and it makes me worry about running pressures even close to 40, which I do. I usually run higher on the way to the trail, on the road, and then drop pressure at the trail head.

Words?
Mavic says that running a tire wider than 28 mm voids the waranty on the OpenPro regaurdless of tire pressure. We have built 9er wheels on Open Pro rims with no problems.
 

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IBIKEAZ said:
I just mounted up a Mythos tire to the new Stan's Olympic 29er rim. I used the rim strip. Wow! I am impressed how tight it fits. I mounted it up (took tire lever to get it on) and it fits really tight. I followed Stan's recommendation to air it up before putting in the latex goo. It aired up quickly with just the floor pump and held air well. It was really hard to get the bead off the rim again, it took a wet tire lever to do it. I then added the stuff and did all the tricks the website video's said to do. Aired up in less time than a tube would. The tight fit really lends to confidence. I am trying this on the back first so far due to a ripped liner. After having the Dyad rims (with the loose fitting tires and having tubes blow out the sides because of the loose fit) I am happy with how well the tire fits on this rim. I will be trying these out on the trail soon.

Yes, Im impressed so far. I just set some of these up too with the new Kevlar Nanoraptors. I just used the yellow tape, not the rubber rim strip and I put dish soap on just one bead (one side) and it aired right up with just a floor pump. Very nice and very very tight fit! In my haste to mount these I put the rear one on backwards. I put one ride on them before turning the tire around and when I went to pull it off the bead was really seated or fitted into the rim socket. Very nice, solid interface between the tire and rim it seems. Has a real nice pop when the bead seats too. The second time airing them up, they needed no soap, just pumped a couple strokes and they seated instantly. Im real happy with the way these worked so easily. Even at 15 psi ( I never ride less than 30psi typically) I could not get the tire to "burp" air. Now the ride tests! So far so good. :)

Oh and the 1530 gram complete disc wheelset weigh doesnt hurt either. So far this seems like the way to go.
 

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Stan

JMKM said:
I was interested in these rims because of their weight and reputation, but then I went on Stan's site and noticed the Max PSI rating of 42 for all of his rims. This makes me worry about the durability of the rim over year's of riding. Sure, if I'm going to plan on rebuilding the wheelset every year or couple of year's it makes sense. It seems to me though this max 42 psi rating is a result of the rims extrusion shape failing over time if the rim is run at higher pressures. I know not many of us run at pressures over 40, but it just concerns me. I've never seen a max pressure rating on a rim before and their are quite a few sub 400g rims out their for road use. Like Mavic Open Pros, Velocity Razors and Aeroheads. They may be a couple millimeter's narrower, but they don't have a max psi rating.

This makes me think that the durability of this rim over several years isn't good and it makes me worry about running pressures even close to 40, which I do. I usually run higher on the way to the trail, on the road, and then drop pressure at the trail head.

Words?
I spoke to Stan and he likes to talk.....allot :) He is concerned (really concerned) about picking the correct (tight fitting) tire for tubeless applications when using his Olympic 29” rim. If you use a tube no worries. Personally I have not decided to go tubeless or use a tube.
 

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Non Dual Bliss
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EPO said:
Sometime my ******* Math works, but in this case the stress in the rim due to pressure is not a function of tire size. The stress in the rim is due to pressure and rim geometry alone irreguardless of tire size.

Stan's 42psi max is a safety factor blow off thing.

EPO
I think I'd have to disagree. Here's the logic of my thinking: the total pressure within the tire (surface area x PSI) is trying to exand the bead away from the rim. Without the bead, the tire will not stay in place. It has been shown that cutting the tire bead perpindicular to the rim around the tire will not cause the bead to unseat, i.e., the tire does not rely on a contiguous bead to remain seated, it relies on the bead's shape and position relative to the rim hook and sufficient outward pressure to keep it there. This should demonstrate that it is not the bead circumfrence that keeps the bead in place but rather the outward pressure on the tire bead keeping it seated in the rim hook and both being able to resist the total pressure within the tire. The rim will see an exspansive force along the perimeter of the bead at the same rate as tire pressure, but it also must withstand a pulling force caused by the total pressure within the tire.

Poke holes wherever you see fit.
 
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