# Tubless tire = 25kg spoke tension drop?!



## rruff (Feb 28, 2006)

Seriously. Mounted a set of Fusion 3s on Alpha 340 rims. After pumping the tire up (100psi) I noticed that the spokes *felt* loose, so I checked them. Yep... ~25kg lower front and back. Let out the pressure and checked again... back to normal. It even threw the dish off on the rear wheel a significant amount. 

It's normal for tire pressure to reduce the diameter of the rim a little and this reduces the spoke tension a little... maybe 5-10kg. I checked another Alpha 340 with a tubed tire and the change was 5-10kg. 

Is this normal for tubeless tires? If so, I don't understand why it would be different than with a tube.


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## bholwell (Jan 22, 2008)

I noticed the same thing. I think it's more of a function of the rim. The Alpha 340 rims (and all other Stan's rims) are designed to have a nice interference fit between the rim and the bead. The inside diameter of a tubeless road tire is smaller than that of a normal clincher with aramid beads.The carbon fiber beads also have very little elasticity. And of course the Alpha 340's are very light.

When I first received my Alpha wheelset and mounted a pair of tubeless road tires, I was alarmed at the noticeable drop in spoke tension. (I can't tell you how much, exactly, as I don't own a spoke tensiometer.) Before even riding the wheelset, I brought up the spoke tension.


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## brians647 (Mar 2, 2007)

That's a big drop.
I can't understand why it happens in a tubless tire at all (tubed, and tubies, I get).
I also don't get why it would affect dish.


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## Kerry Irons (Feb 25, 2002)

*Understanding*



brians647 said:


> That's a big drop. I can't understand why it happens in a tubless tire at all (tubed, and tubies, I get). I also don't get why it would affect dish.


The force applied by the pressure in the tire has to go somewhere, and apparently the rim design is such that when you apply pressure to the sidewalls and the spoke bed, it causes the rim to shrink a bit. Since the drive side spokes are under higher tension, it's easy to see why reducing overall rim diameter could cause the rim to shift toward one side. Agreed that this is a lot of tension drop from pumping up the tires.


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## TomH (Oct 6, 2008)

Im curious what would happen if you put a tubed tire in that specific set of wheels..


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## brians647 (Mar 2, 2007)

TomH said:


> Im curious what would happen if you put a tubed tire in that specific set of wheels..


I've been mulling that over since I posted.
Technically, if a high-pressure pocket of air is the culprit, then inserting another layer of flexible rubber in between that pocket of air and the rim should have little/no effect.
I think...


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## cfoster (Dec 20, 2007)

TomH said:


> Im curious what would happen if you put a tubed tire in that specific set of wheels..


I was wondering that exact same thing myself. The drop in spoke tension sounds like a lot, inflating a tire shouldn't require having to re-dish the wheel. I can't help but wonder if there's some other kind of anomally here at play?

Even "softer" rims will compress sufficiently under spoke tension such that the additional pressure from an inflated tire doesn't throw it out of whack. 25 Kgf just sounds like something is amiss, like the original spoke tension reading was on a spoke that hadn't been stress relieved, and then the tire pressure compressed the rim enough to stress the rim/spokes causing the sudden drop in tension. When it went out of dish was it still true, or was it "out of dish" only in spots? If you took the tire off and the spoke tension went back to the first reading though, I have to scratch my head....


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## rruff (Feb 28, 2006)

TomH said:


> Im curious what would happen if you put a tubed tire in that specific set of wheels..


They are the same rims and spokes and spoke count as my personal wheels... and I don't see anywhere near that kind of tension drop... 10kg max. I have a 23mm GP4000 on the rear and a 20mm on the front. 

That's the biggest mystery to me... why so different?


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## rruff (Feb 28, 2006)

cfoster said:


> When it went out of dish was it still true, or was it "out of dish" only in spots? If you took the tire off and the spoke tension went back to the first reading though, I have to scratch my head....


Completely stress-relieved... still true, just the wrong dish... which you would expect since a change in rim diameter would alter the tension ratio. All the spoke tensions were even, just ~25kg less than without the tire. Front wheel also. 

Time to check out the Stan's forum I think...


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## bholwell (Jan 22, 2008)

rruff said:


> They are the same rims and spokes and spoke count as my personal wheels... and I don't see anywhere near that kind of tension drop... 10kg max. I have a 23mm GP4000 on the rear and a 20mm on the front.
> 
> That's the biggest mystery to me... why so different?


I'm trying to tell you guys, it's the carbon fiber bead of the tubeless road tires that causes the spoke tension drop with the Alpha 340 rims. The tubeless road beads have a smaller inner diameter, and they don't stretch nearly as much as aramid beads. So when the tire's air pressure forces the beads up onto the bead shelf, the beads act like huge, strong rubber bands around the entire rim, compressing it. Of course the tire's air pressure compresses the tire also.

This should give you some insight into the strength of the carbon fiber beads. :wink:


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## rruff (Feb 28, 2006)

So far no answer from the Stan's guys... but someone chimed in that they got a similar tension drop with MTB wheels. 

There could be something about the design of the tubeless tires that makes them create a higher force on the rim. Not just the bead, but the way the casing is designed. If it's a "normal" thing I'll be needing to build wheels differently depending on the type of tire used... weird.


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## rruff (Feb 28, 2006)

Yes... found this by Mark McMaster (who seems to know just about everything) on weightweenies, about the Maxxis Radiale. So Hutchinson might be making the casing plys at a more acute angle so the tire is very tight to the rim when pumped up.

"The air pressure in the tire acts on the casing threads in two ways - the pressure across the sides of the tire (minor diameter) try to make the tire fatter, which pulls on the casing threads by trying to make them more perpendicular to the direction of travel; and the pressure acting on the length of the tire tries to make the tire bigger in major diameter, which pulls on the casing treads by trying to make them more tangential to the direction of travel. These two forces are balanced out when the casing treads are at 52 degrees to the direction of travel. That means that if the casing treads start at 45 degrees, air pressure tries to re-orient them steeper, with the overall affect of making the tire fatter but smaller in major diameter. If you've ever inflated a tubular tire off the rim you've seen this actually happen - an inflated tubular tire is smaller in major diameter than an un-inflated tire.

For a tubular tire, this is a good thing, as the tire naturally constricts on the rim when it is inflated, allowing the tire to hold the rim better. Even on clincher tires the casing has a constricting affect - this can be demonstrated by noting that air pressure decreases spoke tension, as the tire consticts onto the rim.

If the casing threads on a 'radial' tire are at greater than 52 degrees, then air pressure will have the opposite affect - the tire will actually try to increase in major diameter, pulling away from the rim. This tendency to increase in major diameter must be countered by circumferential belting, to hold the tire to its original diameter. I wouldn't at all be surprised that the reason the Panaracer Radiale tire is so tough to install is that the designers had to counter the tendency for the tire to increase diameter when inflated by decreasing the free (in-inflated) diameter."


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## TomH (Oct 6, 2008)

How many other rims have a severe drop in tension with tubeless tires? Seems like stans rims dont have a ton going for them except the weight.


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## bholwell (Jan 22, 2008)

TomH said:


> How many other rims have a severe drop in tension with tubeless tires? Seems like stans rims dont have a ton going for them except the weight.


Well, most other tubeless road rims are a bit on the heavy side. They also conform to the road tubeless standard. Stan's rims are sort of in a class by themselves: very lightweight, wider than most, if not all, and relies on an oversized bead seat diameter for a tight fit between the bead and the rim.

One thing the Alpha rims definitely have going for them is the extra volume they lend to a tire. My Padrones average out to 23.1mm wide at 100 psi on Dura-Ace 7850 rims (which are relatively wide- 15.3mm internal, I believe). The same tire mounted on an Alpha rim (17mm internal width) measures 23.9mm wide at 100 psi. It might not sound like a huge difference, but yesterday I did a group ride which went over a lot of crack sealed pavement. The Alpha rims were noticeably more comfortable than the Dura-Aces. Part of it could be more vertical compliance, though. The downside might be one should to run a higher number of spokes to retain lateral stiffness, and should check the spoke tension once tires are mounted. But I think the weight and comfort benefits are worth it.


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## rruff (Feb 28, 2006)

No response yet from Stan's. Surely there are a few people here with a tensiometer who have tubeless tires... anybody?


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## Lab Worker (May 31, 2004)

rruff said:


> No response yet from Stan's. Surely there are a few people here with a tensiometer who have tubeless tires... anybody?


I noticed it on the first pair I built - I inflated the tires overnight to see if they'd hold air without sealant. I just happened to squeeze the spokes the next day and I thought I'd forgotten to finish adding tension to the wheel they were so loose. I passed some feedback through to Stan's via our local distributor but didn't hear much back. On an unrelated question about tubeless road rims they told me "The Alpha is more stiff both laterally and vertically than the 355" but I've never noticed such spoke tension drops with running tubeless road tyres on the old 355.

The spoke tension on Stans factory-built wheels with the Alpha 340 which I've measured is 1300kgf on the DS - well over their 1000kgf 'max' so this is what I build to. I also dish the wheel 0.5mm towards the DS.

Where ever possible I sell / fit the tubeless tyres so that I can check the final result with the tyres inflated.

I've found the Alpha 340s lateral stiffness and dent resistance to be somewhat lacking so I'm generally pretty conservative about who I sell these rims to - generally light riders with a decent amount of spokes.


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## worthcycle (Apr 13, 2011)

I am seeing a large tension drop on sets of wheels I just finished in the last few weeks - not a measured drop since I don't use a tensionometer. But the difference was amazing! At least a turn and a half needed to re-tension correctly.

I have built an identical set of wheels using the HED C2 rims and the tension did not change noticeably on those wheels with the same tubeless tires (Hutchinson Fusion 3).

In thinking about it over the last few days my theory was that the rim must be changing in shape due the unique profile of the Stan's 340 rim - possibly due to the curved dip in the center of the rim that could allow the rim to elongate when the tire pulls on it. I am not sure though, just a guess!


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## rruff (Feb 28, 2006)

worthcycle said:


> In thinking about it over the last few days my theory was that the rim must be changing in shape due the unique profile of the Stan's 340 rim - possibly due to the curved dip in the center of the rim that could allow the rim to elongate when the tire pulls on it. I am not sure though, just a guess!


Well, I'm leaning towards blaming it on the tire... since it doesn't happen with the normal tubed tires on that rim. And some tubeless tires could be different also.


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## rruff (Feb 28, 2006)

Lab Worker said:


> I've found the Alpha 340s lateral stiffness and dent resistance to be somewhat lacking so I'm generally pretty conservative about who I sell these rims to - generally light riders with a decent amount of spokes.


Dent resistance... well... you gotta expect something like that to happen if you bottom out the tire. Those little hooks are very thin. The joy of running low pressure and still avoiding pinch flats can get nullified when you dent the rims...

I think the stiffness is really good for the weight. Of course something like the XR270 is stiffer, but it weighs almost 100g more. I also like the way that tires sit on the bead socket... makes them rounder and wider.


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## ColoRoadie (Aug 5, 2010)

If they are dropping that much tension with tubeless tires, do you leave it alone or twist them back up to tension?


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## rruff (Feb 28, 2006)

ColoRoadie said:


> If they are dropping that much tension with tubeless tires, do you leave it alone or twist them back up to tension?


*If* the tubeless tire that is used drops the tension that much, then the tension needs to be increased. The problem is that the build tension depends on what tire is mounted. On such a light rim I don't think it is a good idea to tension them all for worst case, because if regular tires are used the tension will be too high.


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## Kerry Irons (Feb 25, 2002)

*Tire blame?*



rruff said:


> Well, I'm leaning towards blaming it on the tire... since it doesn't happen with the normal tubed tires on that rim. And some tubeless tires could be different also.


I having a hard time seeing how the forces on the rim would be any different with a tube installed or without. Are you saying tire sidewall stiffness is the cause? Compared to the pressure of 90 psi, sidewall stiffness is pretty small. Could you expand on this a bit?


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## rruff (Feb 28, 2006)

See post #12 where I give Mark McMaster's explanation of how casing ply angles effect the tire diameter when pressure is applied. I don't have any other evidence of this, but it sort of makes sense that Hutchinson would make their tubeless tires so that they would get very tight when pumped up.


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## bholwell (Jan 22, 2008)

rruff said:


> See post #12 where I give Mark McMaster's explanation of how casing ply angles effect the tire diameter when pressure is applied. I don't have any other evidence of this, but it sort of makes sense that Hutchinson would make their tubeless tires so that they would get very tight when pumped up.


It's not the casing, but the beads (in combination with the nature of the rim) that is causing this phenomenon. Read the last line of your post #12. A typical nylon casing is nowhere near strong enough to excert such a force.

At the risk of sounding repetitive, the inner diameter of a tubeless road tire's bead is around 621mm. They also do not stretch. Compared to an aramid bead, which typically stretches to about 622.6mm or more, the difference is huge.


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## rruff (Feb 28, 2006)

If the bead is the issue then why is there no problem until the tire is pumped up? 

I also don't see how the last line of #12 supports your point. The Hutchinson tires are not Radiales. Most clinchers are biased at 45 degrees, and *do* become smaller when inflated and compress the rim. It is possible that Hutchinson made their tubeless tires with a shallower angle so the tire would be extra tight. Or maybe the combination of 45 degree bias with a carbon bead is enough to do it.


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## bholwell (Jan 22, 2008)

rruff said:


> If the bead is the issue then why is there no problem until the tire is pumped up?


Because the beads don't seat onto the bead shelf until the tires are inflated to around 80 psi. It takes this much pressure to force the beads up onto the bead shelf, which is simutaneusly stretching the beads and compressing the rim. The carbon fiber beads have a miniscule amount of stretch to them compared to aramid beads. Release the air pressure, and the beads fall back down into the center channel, and all compressive force is removed.

It's the combination of three things that is resulting in the large spoke tension drop seen in the Alpha 340 rims with tubeless road tires:
1) Air pressure pressing radially around the circumference of the rim (also seen in all clincher rims).
2) Inelastic carbon fiber beads that compress the rim at the bead seat shelf. The diameter of this bead seat shelf is larger than that of standard tubeless road rims.
3) A much thinner rim extrusion



rruff said:


> I also don't see how the last line of #12 supports your point. The Hutchinson tires are not Radiales. Most clinchers are biased at 45 degrees, and *do* become smaller when inflated and compress the rim. It is possible that Hutchinson made their tubeless tires with a shallower angle so the tire would be extra tight. Or maybe the combination of 45 degree bias with a carbon bead is enough to do it.


Only tubulars really compress the rim as the tire is inflated. All clinchers expand. Mark was wrong in that it's the air pressure acting "downward" all around the rim that compresses a standard clincher rim, and results in a reduction of spoke tension. Most beads do not actually sit on the bead seat shelf once the tire is inflated (the exception to this is tubeless road tires, UST tires on UST rims, and stan's ZTR rims with normal clinchers). So unless the casing and bead is sitting down on the bead seat shelf, there is no way for the tire to transmit a compressive force. The point Mark was trying to make is that the steeper angle of the casing threads in a radial tire will want to make the tire expand more so than a normal biased tire (which is true). Therefore the tire and beads need to be undersized to resist this additional force.


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## rruff (Feb 28, 2006)

bholwell said:


> Only tubulars really compress the rim as the tire is inflated.


Why is it different?



> Most beads do not actually sit on the bead seat shelf once the tire is inflated (the exception to this is tubeless road tires, UST tires on UST rims, and stan's ZTR rims with normal clinchers). So unless the casing and bead is sitting down on the bead seat shelf, there is no way for the tire to transmit a compressive force.


Eh? Call it what you like, but all clinchers have a "shelf" in the same location where the bead sits. It can transmit a compressive force there just as easily as it can on the tubeless rims. The "shelf" on the 340 appears to be at the same diameter as it is on other rims.


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## bholwell (Jan 22, 2008)

rruff said:


> Why is it different?


Because only tubulars are self-contained pressure vessels. The are designed to expand three dimensionally when inflated. As the cross section expands, the inner diameter of the tire shrinks, effectively compressing the rim.




rruff said:


> Eh? Call it what you like, but all clinchers have a "shelf" in the same location where the bead sits. It can transmit a compressive force there just as easily as it can on the tubeless rims. The "shelf" on the 340 appears to be at the same diameter as it is on other rims.


Before tubeless road there was no standard among road rims. The bead shelf diameter and the rim wall heights are all over the place, from manufacturer to manufacturer. I once had some reynolds rims that actually had no bead shelf. I had to pay close attention while inflating the tire to make sure that the tire was evenly seated around the circumference of the rim.

The bead shelf on the Alpha 340 rim is substantially larger than that of a normal clincher rim. It's also larger than that of a road tubeless rim. You wouldn't be able to tell a difference by looking at it, we're talking <2mm, which is a large number when dealing with bead tolerances. But my equipment allows me to measure the inner diameter of beads and a rim's bead shelf diameter with a +/-0.05mm accuracy.


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## worthcycle (Apr 13, 2011)

*Bead Shelf Diameter*

So from what I gather the idea is that the bead seat diameter geometry on the Alpha 340 rim makes a tubeless tire, which have a tighter and strechless bead, constrict the diameter of the rim - decreasing the overall diameter of the whole rim - thus reducing spoke tension?

Since the Stan's rim geometry is unique in the road rim market, with the pronounced bead seat shoulders, it makes since why the tension problems haven't been seen with any other wheel or rim configurations to the degree that is occurring with these rims.

rruff's prescription of re-dishing and re-tensioning is going to be required for these rims...

With that in mind I have 2 sets of wheels to rework as we speak!


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## FTR (Sep 20, 2006)

Yes, this is a known problem that I was warned about by a local supplier.


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## bholwell (Jan 22, 2008)

FTR said:


> Yes, this is a known problem that I was warned about by a local supplier.


I don't see it as a problem, but rather as an extra step for the wheelbuilder whose customer chooses to ride tubeless tires. The lightness of the rims, the extra volume they lend to tires, and their comfort definitely make it worth it, imo.


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## Jeremyinlinepro (Jan 8, 2010)

Its funny, I am new to wheel building and built up my 3rd set of rims with Stans Alpha 340 & tubeless Fusions. The same thing happened with my rear wheel. It lost close to 30kg. I thought I was doing something wrong. I searched but found no information on loss of spoke tension with the tire inflated. I ended up tensioning it to 90-95kg with the tire inflated. First ride on the wheels I hit a pothole and bent the rim to unusable condition. I am going to change the rim out for a Hed Belgium C2. Its just nice to see this thread to know I wasn't doing something wrong


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## hacklnh (May 16, 2011)

*I Experienced Same Tension Loss with Standard Tire*

I recently built a set and noticed the same tension loss using a Michelin Pro Race 2. The NDS spokes had no tension at all after inflation.

The only solution I can come up with is to tension the wheel beyond what Stan's recommends.


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## ukbloke (Sep 1, 2007)

A recent discussion thread over at notubes.com confirms bholwell's assertion that the main factor is the bead is squashing the rim. Air pressure is needed to mount the bead, but you can then release the air pressure while the bead stays mounted and the spoke tension loss remains. The spoke tension goes back to normal when you pop the bead off.

I was thinking about a PowerTap build with this rim to get the benefits of road tubeless and a relatively lightweight build. This thread has completely dissuaded me from doing this. So many thanks for the info! If I do this I'll go with a "standard" road tubeless rim, not with Stans.


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## rruff (Feb 28, 2006)

ukbloke said:


> I was thinking about a PowerTap build with this rim to get the benefits of road tubeless and a relatively lightweight build. This thread has completely dissuaded me from doing this.


I wonder why. Do the final tensioning with a tire mounted and be done. You won't ever ride them without an inflated tire, so the uninflated tension is irrelevant. 

I have *not* seen a significant tension change with the Conti GP4000 or SS, or the Veloflex Corsa. Only the Fusion 3.


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## ukbloke (Sep 1, 2007)

rruff said:


> I wonder why. Do the final tensioning with a tire mounted and be done. You won't ever ride them without an inflated tire, so the uninflated tension is irrelevant.
> 
> I have *not* seen a significant tension change with the Conti GP4000 or SS, or the Veloflex Corsa. Only the Fusion 3.


Thanks, I see your point, but I'm just cautious, arguably overly so. It just sounds too close to the ragged edge to me. I love my Shimano WH-7850-SL's because of road tubeless but also because I never have to do a thing to them. I just get the feeling that this Stans Alpha rim is going to be maintenance trouble for the long-term. I was already somewhat concerned about life-time of the braking surface with a lightweight rim. I like my (wired) PowerTap Open Pro wheel, but disappointed that I can't have everything that I want at the same time. I'm coming around to the conclusion that I'm going to have to get my power from elsewhere, either a Quarq crank or the yet-to-be-released Garmin Vector.


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## purdyd (Jun 18, 2010)

ukbloke said:


> A recent discussion thread over at notubes.com confirms bholwell's assertion that the main factor is the bead is squashing the rim. Air pressure is needed to mount the bead, but you can then release the air pressure while the bead stays mounted and the spoke tension loss remains. The spoke tension goes back to normal when you pop the bead off.
> 
> I was thinking about a PowerTap build with this rim to get the benefits of road tubeless and a relatively lightweight build. This thread has completely dissuaded me from doing this. So many thanks for the info! If I do this I'll go with a "standard" road tubeless rim, not with Stans.


i aint buying the bead squashing the rim theory, it obviously does when you let the air out and it stays seated but the tension goes up as you pump more air into the tire after the bead is seated

and it was the air that pushed the bead in to begin with, not the rim pushing the tire

and the Stan's don't lock the same as the Shimano's, you can ride on Shimano rim with a flat tubeless tire and Stan's the bead will pop right when the tire is flat if you just look at them

and my shimano wh-7850's have a spoke tension drop too, just not as big a deal since they have more tension to begin with vice the Stan's

and just for grins, I put on a pair of IRC formula pro's and get the same drop in spoke tension as the fusion 3


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## valleycyclist (Nov 1, 2009)

rruff said:


> I wonder why. Do the final tensioning with a tire mounted and be done. You won't ever ride them without an inflated tire, so the uninflated tension is irrelevant.
> 
> I have *not* seen a significant tension change with the Conti GP4000 or SS, or the Veloflex Corsa. Only the Fusion 3.


I just measured about a 25% tension drop with a used Michelin Pro3 Race tire. (24 spoke rear wheel with CX-Ray spokes and a Dura-Ace 7900 hub). I tensioned the rim to 120KgF without the tire to get about 850-900KgF with the tire installed and inflated to 110PSI. I do not have a GP4000, but it would be interesting to try one.

I swapped that tire with a new Continental Gatorskin (folding) and noticed a similar drop.

Spoke tension was measured with a DT Swiss tensiometer.


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## rruff (Feb 28, 2006)

I just checked a Pro3 and this is what I get for DS tension:

Tire in center channel: 115kg
Tire on bead shelf but deflated: 100kg
Tire inflated to 100psi: 90kg

That is more than I expected. I think I failed to move the tire bead into the center channel before, which is why I got smaller differences.


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## valleycyclist (Nov 1, 2009)

That is pretty close to what I measured. Thanks for sharing.

Looking at the NoTubes forum, I learned that they use green Loctite 290 on the spoke threads of their factory wheels. I replaced a spoke for someone who had an early build of the Alpha Pro wheelset, and the spokes did not have a threadlocker, so perhaps Loctite is used on the newer factory builds. This indicates to me that the tension loss when tires are installed is a big problem.

It seems that since they lose so much tension that it is best to aim for 120Kg on the DS. It makes it more complicated if different tires cause different amounts of tension decrease. I plan to be at Interbike, and I hope I have a chance to discuss this with NoTubes. Postings on their forum say to aim for 95Kg without a tire installed.


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## ukbloke (Sep 1, 2007)

I recently had to replace a broken spoke on my Shimano WH-7850SL front wheel which is set up as road tubeless with Fusion 2 tires. Out of curiousity, I measured spoke tension and saw about a 10% drop in tension from no tire mounted to tire mounted and inflated to 90psi. I then deflated the tire leaving the bead mounted and the tension was more or less in the middle of the previous two measurements - so there was a measurable effect on spoke tension both from the bead and from air pressure. That's pretty consistent with rruff's observations, though significantly less tension loss with the Shimano wheel build compared to the Alpha rim.


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## purdyd (Jun 18, 2010)

ukbloke said:


> I recently had to replace a broken spoke on my Shimano WH-7850SL front wheel which is set up as road tubeless with Fusion 2 tires. Out of curiousity, I measured spoke tension and saw about a 10% drop in tension from no tire mounted to tire mounted and inflated to 90psi. I then deflated the tire leaving the bead mounted and the tension was more or less in the middle of the previous two measurements - so there was a measurable effect on spoke tension both from the bead and from air pressure. That's pretty consistent with rruff's observations, though significantly less tension loss with the Shimano wheel build compared to the Alpha rim.


yeah, but the 7850's factory have a lot more tension to begin with and so in absolute terms, i think it is about the same drop - also, with all that tension on the spoke, a small change in the spoke tension measurement, is a larger change in spoke tension

i played around one day and even have some IRC tubeless tires and all tires dropped spoke tension in all wheels

tubed tires were less and tubeless were more

and tubeless stans or shimano with IRC or hutchinson fusion/atom were all around the same

i also learned how imprecise the park spoke tension gauge is 

i have about 3000 miles on my stans now and while i have had to true the rear a couple of times, they are holding up quite well and seem to have been built to match Stan's recommendations for spoke tension, at least on the front


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## valleycyclist (Nov 1, 2009)

valleycyclist said:


> I plan to be at Interbike, and I hope I have a chance to discuss this with NoTubes.


As promised, I have an update to the Alpha 340 rim build process. I was told that the current factory build process is to aim for 115kg tension and to use nipple washers.


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## Lab Worker (May 31, 2004)

valleycyclist said:


> As promised, I have an update to the Alpha 340 rim build process. I was told that the current factory build process is to aim for 115kg tension and to use nipple washers.


Their factory builds, at least the ones I've had anything to do with, don't use any nipple washers.


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## Crawf (Oct 21, 2010)

valleycyclist said:


> As promised, I have an update to the Alpha 340 rim build process. I was told that the current factory build process is to aim for 115kg tension and to use nipple washers.


Silly question but, is that 115... deflated no tyre mounted OR (tubeless) mounted deflated OR (tubeless) mounted inflated?


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## valleycyclist (Nov 1, 2009)

Crawf said:


> Silly question but, is that 115... deflated no tyre mounted OR (tubeless) mounted deflated OR (tubeless) mounted inflated?


That is with no tire mounted, as far as I know. That tension makes sense to me based on my experience with the rims.

They had a nice display at Interbike. It was fun to watch them stab tires with picks and watch them seal. I think the new decals on the rims look nice too.

As a side note I asked Velocity about running tubeless on their rims. The guy I talked to said he is running tubeless on A23 rims without problems (using the Velocity VeloTape), but he prefers the ride quality of GP4000+tube to the tubeless setup.


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## rruff (Feb 28, 2006)

valleycyclist said:


> That tension makes sense to me based on my experience with the rims.


Also note that dishing the rear wheel slightly towards the NDS is a good idea.


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