so apparently easton is switching to straight pull spokes, and abandoning their T3 technology. Personally, i was buying into all of that, and believed there was an advantage to the dual threading...force is spread farther throughout the spoke and whatnot....

my question is this...(engineers especially) is easton simply trying to make their wheels more servicable with this move, or was there no honest advantage to their T3 stuff??

where did you hear Easton was getting rid of the T3 tech. Everything I have read says all there high end wheels (ascent, orion etc.) will have T3 tech along with completely redesigned hubs and rims. I will check the easton book at our shop tomarrow but was unaware of them getting rid of T3 tech.

http://www.cyclingnews.com/tech/2006/shows/interbike06/?id=results/interbike0610

"Easton’s road wheelsets all receive substantial revisions. Last year’s Ascent II becomes the EA90 SLX, the Orion II transforms into the EA90 SL, and an all-new EC70 SL carbon clincher joins the Easton family. All wheels receive a new R4 hubset, which abandons the long-standing dual-threaded T3 spoking system in favor of a more conventional straight-pull design. Rear freehubs get an upgrade from 24 to 32 ratchet teeth for faster engagement, and larger diameter aluminum axles front and rear increase lateral rigidity and bearing durability."

The serviceability issue scared me off on the Orions. I acutally bought some and sent them back without opening the box. I didn't realize at the time of purchase the spokes would be hard to replace. When I asked my LBS about Easton/Velomax wheels they recommended I find something with more traditional spokes. I may take a look at the 07 version now.

http://www.cyclingnews.com/tech/2006/shows/interbike06/?id=results/interbike0610

"Easton’s road wheelsets all receive substantial revisions. Last year’s Ascent II becomes the EA90 SLX, the Orion II transforms into the EA90 SL, and an all-new EC70 SL carbon clincher joins the Easton family. All wheels receive a new R4 hubset, which abandons the long-standing dual-threaded T3 spoking system in favor of a more conventional straight-pull design. Rear freehubs get an upgrade from 24 to 32 ratchet teeth for faster engagement, and larger diameter aluminum axles front and rear increase lateral rigidity and bearing durability."

This sounds like they are finally admitting what everyone has known all along - that dual threaded spokes are not more reliable than properly shaped, supported and stress relieved heads and/or elbows. In fact, if the heads/elbows are properly supported/stress-relieved, the threads are actually the weakest part of the spoke.

The only real purpose of dual threaded spokes were for product differentiation (i.e. for marketting and "hype" purposes).

are u an engineer or is that ur opinion

i've personally never blown spokes out of the nipples.....(rolls eyes)

are u an engineer or is that ur opinion

i've personally never blown spokes out of the nipples.....(rolls eyes)

Those aren't exclusive - even being an engineer, it's still an opinion. But one that is probably correct.

Short version, the hub likes it better in terms of strength/weight performance, but the spoke likes it less. Net the gains and losses, and it's probably not a good trade-off. It's a way to make lighter wheels, but not a way to make stronger wheels (or for that matter, wheels that are equally strong but meaningfully lighter.)

Those aren't exclusive - even being an engineer, it's still an opinion. But one that is probably correct.

point taken. but i was looking for a little more information than a blatant "sez you" response

Short version, the hub likes it better in terms of strength/weight performance, but the spoke likes it less. Net the gains and losses, and it's probably not a good trade-off. It's a way to make lighter wheels, but not a way to make stronger wheels (or for that matter, wheels that are equally strong but meaningfully lighter.)

i still dont' understand why the spoke won't like it. the force is spread through a larger area, rather than one small point....makes sense to me.

but, even if it doesn't...u still conceded that it will make a lighter combination :D even though the hubs on those things aren't exactly weight weenie material (look at the size of that drive side flange) :eek: oh well.

are u an engineer or is that ur opinion

Both. I have a B.S. and M.S. in mechanical engineering, and have worked as an engineer for 20 years. And it is my opinion that dual threaded spokes are no more reliable than properly designed and constructed spoke heads and elbows.


i've personally never blown spokes out of the nipples.....(rolls eyes)

In addition to being an engineer, I have also been a part time wheel builder. Of the 150+ wheels I've built, one has broken a spoke at the nipple, and one has broken a spoke at the elbow. (There have been a number of other broken spokes, but these spokes broke in the middle due - either due to skewers or pedals going into the spokes in crashes, or the spokes getting chewed through by a chain getting caught between the sprocket and spokes.)

Unfortunately, it seems that few wheel builders take the time to make sure the spoke elbows are properly supported and stress relieved. Spokes should fit snuggly against the flange, to reduce bending stresses. Spoke head washers can be used to take up slack if the elbows are longer than the flange width. The spoke lines need to be corrected (spokes pre-bent into the angle that they will take in the finished wheel), also to reduce stresses in use. And spokes need to be stress-relieved. This does two things - it "beds" the spoke elbow into the flange (creates an indentation into the flange that better matches the shape of the elbow to better support the elbow) and reduces the residual stresses in the elbow. If these steps are properly done, the elbow can be less fatigue prone than the threads.

Unfortunately, it appears that many people that call themselves wheel builders don't understand or employ these steps to enhance the integrity of the spoke elbow, the result being a lot of (unnecessary) spoke elbow breakages.

awesome. just what i wanted to hear.


thank you very much for your response.

now i have another question....

since it is obvious that manufacturers will not go to proper lengths to ensure these high quality builds (never have i seen the utilization of spoke washers), do you think it would be a better idea to go with a dual thread design, as this will obviously nullify all spoke elbow issues?

I spoke with an inside rep for easton Today, here is what he said. For 2007 the Easton Catalog will have Tempest and Circuit wheels which both use T3 spoke technology. Also while not in the Easton catalog the Easton 2007 price sheet lists the Ascent and Orion wheels as well, they also use T3 tech. These wheelsets will be available for the remainder of 2007 according to the rep. So that makes four sets of wheels for 2007 with the T3 spoke tech, but the rep would not say if Easton will abandon the T3 spoke lacing for good in the future.

Our shop does not stock Easton wheels, but we do have a few customers on older Velomax wheels all with good things to say. As for whether T3 is better than conventional spokes I will leave that debate up to people who think they have the answer. My only take is that if the j-bend spoke was so bad it would have been replaced many decades ago. Personally I think a properly built and tensioned wheels matters a whole lot more than the components used to build it. Which is why I dont build my own wheels, rather I have someone who knows a hell of a lot more about building wheels do it for me.

since it is obvious that manufacturers will not go to proper lengths to ensure these high quality builds (never have i seen the utilization of spoke washers), do you think it would be a better idea to go with a dual thread design, as this will obviously nullify all spoke elbow issues?

You can execute either design well or poorly. However, dual thread spokes create a non-standard design that really doesn't solve a problem. As Mark noted, spoke breakage in a properly built wheel is not an issue, so the dual thread design is a solution to a non-problem.

could not have said that better, I see alot of companies out there solving (non-problems). Does not mean that it's bad or good, but it makes you wonder. Are they just coming up with things to be different and sell a few more products. Properly built wheels with j-bend spokes can go for tens of thousands of miles, usually the rim wears out before anything else. I have seen guys wear through the brake track on open pro rims at about 15000 miles, but never had any issues before that. With all that being said I do know some people on older velomax wheels that have had no issues with them for thousands of miles.

there's something to be said for doing something outside the box...it's just a question of how far a consumer is willing to buy into these products rather than stick with tried and true....if u look at the mtb world, everyone thought v-brakes were horrible when they first came out, then discs weren't any good. but as tech evolved, they became the norm. while i'm not saying every manufacturer is going to go T3 tech, i'm saying if it weren't for manufacturers doing stuff outside the box we'd all be riding the same kind of bikes merckx rode in his glory days..(not necessarily a bad thing).

obviously everyone knows this buy i felt a desire to state it

anyway.......i'm grabbing myself a pair of tempests this winter. i'm not too overly concerned with spoke breakage, the specs seem pretty solid (30 mm alloy rim at 1500 g/wheelset. compare to a less aero ksyrium ES at 1485 (?).)

i guess i'll let you guys know if they go bad...hopefully u won't hear from me anytime soon.

Good luck with the wheels, I think you will really like them. Plus with all the money you save over Mavic ES's you could buy more parts.

I'm not sure if the spoke thing does make a difference. What I can say is that these wheels are bomb proof compared to others I've had. So whatever they're doing seems to work.

WBC

I've had my Velomax Circuits for close to 4 years. Not a single problem.
I can't believe how reliable these wheels are. I couldn't care less if its T3, or T23.

It just works.

dual threads may have more to do with spoke tension and stiffness than reliability.

threading as opposed to the j bend is probably stiffer at any given tension because there's a little give at the j bend due to its geometry. also i would think you could tension a straight spoke higher more reliably. these are both just guesses on my part.....but if you look, velomax does seem to run higher tension.

dual threads may have more to do with spoke tension and stiffness than reliability.

threading as opposed to the j bend is probably stiffer at any given tension because there's a little give at the j bend due to its geometry. also i would think you could tension a straight spoke higher more reliably. these are both just guesses on my part.....but if you look, velomax does seem to run higher tension.

The idea that there is appreciable "give" in the spoke elbow is just a wild guess, similar to those who think curved forks have more "give" than straight forks. Both are incorrect, for similar reasons. The spoke elbow simply isn't a large enough part of the spoke to produce any signicant deflection - the long, thin section between the elbow and the threads produced more total deflection than the elbow can.

There is also no reason that double threaded spokes can be used at higher tensions then elbow spokes. The reason is very simple - all spokes operate well below their yield point, because it is the rim, not the spokes, that limit the tension.

sure curved forks have more "give". i have to believe there's some give do to bedding or movement at the j bend and the hub. one of the things velomax talks about is lateral stiffness that behaves linearly.....i don't think they call it linear but that's what they mean

actually this all begs the question ....where did the j bend design come from in the first place? it seems like a poor design from both the spoke and hub point of view. motorcycles got away from it years ago

sure curved forks have more "give". i have to believe there's some give do to bedding or movement at the j bend and the hub.

In both of these cases, the reality is that any additional "give", either in the curve in a fork, or at the bend in the spoke elbow, is drowned out by other factors.

On a fork, the curve is down at the bottom, near the axle, where the bending stresses are the lowest. So any amount of flex here, whether the fork is curved or not, will be much smaller than where the stresses are higher, at the top of the fork, in the crown, and even in the steerer. Hence, any flex in the curved section of the fork is insignificant. Other factors, other than whether the fork is straight or curved, are far more important in terms of fork "give".

A spoke flexes (stretches) along its entire length. The amount of flex in a given section is proportional to cross-sectional area, so there is more flex per unit length in the thinner middle section of a butted spoke than in the thicker ends. The elbow is a very small part of the entire spoke. Plus, it is "bedded" into the flange, so that is well and evenly supported. Any additional flex in the few millimeters of the spoke in the elbow region is dwarfed by the total flex along the rest of the length of the spoke. Hence, whether the spoke is of the dual thread or elbow variety is insignificant. Other factors, most especially spoke length and thickness, are far more important in terms of spoke "give".

one of the things velomax talks about is lateral stiffness that behaves linearly.....i don't think they call it linear but that's what they mean

I'm pretty sure the didn't mean linear either - either that, or they were just making it up. Spokes operate well below their yield point, also known as their elastic limit. In the region of stresses that spokes operate in they behave completely linearly - and that includes whether or not they have an elbow.

i agree with the fundamentals of your argument but i think you're over simplifying what happens at the j bend. i can't prove it. a way to prove it would be to measurre lateral deflection vs load. if there is flex in the j bend then there would be a weird non linear lateral stiffness to the wheel.

as far as forks.....i can see the old steel forks shape as significant ....the new stuff probably doesn't matter....as you said it all happens at the bottom of the steer tube

i agree with the fundamentals of your argument but i think you're over simplifying what happens at the j bend. i can't prove it. a way to prove it would be to measurre lateral deflection vs load. if there is flex in the j bend then there would be a weird non linear lateral stiffness to the wheel.

Why just guess when these measurements have already been made:

Damon Rinard's wheel stiffness test data (http://sheldonbrown.com/rinard/wheel/data.htm)

Looking at the deflection data for Velomax wheels, they are typically flexier than other wheels with similar numbers of spokes. So, those dual threaded spokes by themselves don't appear to be helping to make the wheels stiffer.

I have not ridden tons of wheels. But, I am a big guy, 200 lbs and sometimes over 200 lbs. Lateral stiffness when cornering is something I notice. I have ridden the Orion, 24 / 28 count with 14 / 15 spokes. The Tempest with 18 / 24 count and 2.0mm spokes. Also riden D/A 7800 wheels, I think those are 16 each with 2.0mm. Have ridden K's, everyone knows them. And have ridden Open Pros laced to Ultegra hubs, 32 each with 14 / 15 spokes.

By far the best wheels through a corner were the Easton / Velomax wheels, with the Tempest probably getting the nod. The D/A wheels were very good. The Open / Ultegra were decent. And the K's not that great.

I always assumed that this extra stiffness must be because of the spoke tension. But, whatever the reason, I give a nod to the wheels.

By far the best wheels through a corner were the Easton / Velomax wheels, with the Tempest probably getting the nod. The D/A wheels were very good. The Open / Ultegra were decent. And the K's not that great.

I don't know what property of the wheels give you a better feeling while cornering, but lateral stiffness can't be it. All the Velomax wheels in the test above were very flexible laterally, and the D/A wheels were some of the flexiest in the test. The Open Pro/Ultegra wheels are probably the stiffest wheels of the ones you mention.

I always assumed that this extra stiffness must be because of the spoke tension. But, whatever the reason, I give a nod to the wheels.

As long as none of the spokes completely slackens, spoke tension does not affect stiffness. See question 1 in the discussion portion of Rinard's wheel test (http://sheldonbrown.com/rinard/wheel/index.htm).

All I know is which wheels flexed to rub the brake when cornering hard and which ones didn't. The Tempests were awesome. No matter how hard I took a corner, they never rubbed.

As a side note, isn't the test data in the link kind of irrelevant? The wheels are from 99’, 00' and 01’. The Velomax / Easton wheels have used completely different hubs and rims for the last couple of years. The D/A 7800 wheels are totally redesigned.

Think back to 00’. There was hardly any carbon other than frames and forks. As many people still rode downtube shifters as they did STI. Trying to compare items from 00’ to current day is apples to oranges.

As a side note, isn't the test data in the link kind of irrelevant? The wheels are from 99’, 00' and 01’. The Velomax / Easton wheels have used completely different hubs and rims for the last couple of years. The D/A 7800 wheels are totally redesigned.

The Rinard test data is irrelevent in the small picture, but very relevent in the big picture.

In the small picture, since wheel models change from year to year, you can't necessarily compare this year's model with last year's.

In the big picture, the data shows that the alternative wheel designs (paired spokes, dual threaded nipples, etc., etc.) did not address the issues that the manufacturers claimed they would, so there's no reason to think the new alternative wheel designs will either.

The Rinard test data is irrelevent in the small picture, but very relevent in the big picture.

In the small picture, since wheel models change from year to year, you can't necessarily compare this year's model with last year's.

In the big picture, the data shows that the alternative wheel designs (paired spokes, dual threaded nipples, etc., etc.) did not address the issues that the manufacturers claimed they would, so there's no reason to think the new alternative wheel designs will either.

Hmmmm, I have to disagree with this. Just because the manufacturers did not get it right the first time (and remember, many of these wheels tested are first generation wheels) does not mean they did not improve on their designs. If we use your logic, then because the first generation carbon frames were flexible and prone to reaction with the aluminum parts in them, they are also no good today.

Beyond this, I have two problems with Rinard's test. The first is his choice of a 25.78lb load. He freely admits he choose this amount because it was handy. He assumes this is a greater load than a wheel will see in use. So my question is; is it? What sort of lateral load does a wheel actually see with a 180 lbs rider carving through a crit corner at 25mph? What sort of lateral load does a wheel actually see with that same rider sprinting at 35mph for the finish line?

My second problem is his statement that lateral stiffness is not affected by spoke tension unless the spoke is completely slack. This is counter intuitive to me. While his test may not have shown it, which leads me back to his choice of weight, this just does not seem correct. If we take a spoke, and apply tension, the more tension applied in that direction (between each end) the more that spoke should be able to resist a force from any other direction. It makes me think of rebar in concrete. The rebar is placed under extreme tension and the concrete is poured around it. When the concrete dries, the rebar holds its tension and that is what greatly increases the strength of the finished product. Another way I have heard this explained is if I take a rubber band and hold it between two fingers and stretch is somewhat tight, it will still have some give in the middle if pressed against. But when I stretch it even tighter, it will have less give when pressed against. And when I stretch it nearly to its breaking point, it will have the least give. I would think a spoke should behave the same way. The more tension, the more it will resist flex and the stronger / stiffer it will be.

Mark, you have much more schooling in this area, and much more real world wheel building experience, so I may be completely wrong here, but those are my thoughts.

Hmmmm, I have to disagree with this. Just because the manufacturers did not get it right the first time (and remember, many of these wheels tested are first generation wheels) does not mean they did not improve on their designs. If we use your logic, then because the first generation carbon frames were flexible and prone to reaction with the aluminum parts in them, they are also no good today.

Many of these wheel designs are not first generation. If you look back over the history of the bicycle, you'll seen the same ideas coming up over and over again. And since these designs did not fix anything, they were abandoned. And then a few years later, they come back as "new and improved", and then are abandoned again.

As an example, look at the very oldest wire spoke wheels, from the Hillman and Starley 'Ariel' from 1869 (137 years ago), used wheels with radially laced paired spokes, which used nipples at the hub instead of the rim. When the nipples were moved to the rim, it was an improvement. When spokes were alternated instead of paired, it was an improvement. When spokes were laced tangentially instead of radially, it was an improvement. And yet, all the abandoned features on these first wheels have be re-invented (often several times), and claimed to be "cutting edge technology", despite the fact that they are actually inferior, and have been superceded over a hundred years ago. Most new bicycle wheel design ideas are marketting, nothing more. Rolf, Cane Creek, etc. did not "invent" this new wheel concepts, they are merely re-iterating them.

Beyond this, I have two problems with Rinard's test. The first is his choice of a 25.78lb load. He freely admits he choose this amount because it was handy. He assumes this is a greater load than a wheel will see in use. So my question is; is it? What sort of lateral load does a wheel actually see with a 180 lbs rider carving through a crit corner at 25mph? What sort of lateral load does a wheel actually see with that same rider sprinting at 35mph for the finish line?

Rinard's test is a comparitive test, and since all wheels are tested identically, it is completely valid. Trying to come up with some "representative" load as you suggest is not realistic, since the variation between riders is too large. Would you expect a 100 lb. rider to generate the same wheel loads as a 250 lb. rider? Of course not. There is nothing wrong with Rinard's test method. He accurately measures the stiffness of the wheels in question. How much stiffness is required for a given rider is up to the rider to decide, but Rinard's test does show him which wheels will be stiffier or flexier.

My second problem is his statement that lateral stiffness is not affected by spoke tension unless the spoke is completely slack. This is counter intuitive to me.

This seems to be counterintuitive to a lot of people, but it is completely correct, and backed up by science and engineering. The wheel is linearly elastic, which means that for any additional load applied, it will flex an additional amount in proportion.

As a simple example, take a simple spring scale, such as those used to weigh fish. Say the spring in the scale has a stiffness of 10 lb/in. This means that for each additional 10 lb. that is loaded onto the scale, the spring will stretch 1 inch. If you started with no load on the scale and added 10 lb., the spring will stretch 1 inch. If you started with 20 lb. on the scale (spring pre-stretched 2 inches) and added an additional 10 lb. (total of 30 lb.), the spring will stretch 1 additional inch (3 inches total).

The wheel is similarly linearly elastic. The spoke tension merely adds a preload, it does not change the "spring constant" of the wheel. Looking at the carefully measured data in the Rindard test, who shows that his test wheel does not change deflection with decreasing spoke tension, until the tension is so low that some become completely slack.

While his test may not have shown it, which leads me back to his choice of weight, this just does not seem correct. If we take a spoke, and apply tension, the more tension applied in that direction (between each end) the more that spoke should be able to resist a force from any other direction.

This is moot, since spokes are only loaded in one direction in a wheel - axially. Axially, the spokes are linearly elastic, and have a constant "spring rate"

It makes me think of rebar in concrete. The rebar is placed under extreme tension and the concrete is poured around it. When the concrete dries, the rebar holds its tension and that is what greatly increases the strength of the finished product. Another way I have heard this explained is if I take a rubber band and hold it between two fingers and stretch is somewhat tight, it will still have some give in the middle if pressed against. But when I stretch it even tighter, it will have less give when pressed against. And when I stretch it nearly to its breaking point, it will have the least give. I would think a spoke should behave the same way. The more tension, the more it will resist flex and the stronger / stiffer it will be.

This may be the way pre-stressed concrete was explained to you, but it is incorrect. The reason for the pre-tensioned steel bars is to keep the concrete under compression. Concrete is very strong under compression, but relatively weak under tension. This prevents it from being effective when under a bending load. When a member is under a bending load, the bending generates a tension stress on side of the member, and compression stress on the other side. When a concrete member is under a bending load, the side under tension will fail at a relatively low load, causing the entire member to fail.

If the concrete member is subject to a high pre-compression, it can bear a larger bending load before the tension side of the member fails. What happens in this case is that an external or internal compressive load first applied to the concrete member. Then, as the bending load is applied, it increases the compression on one side, and decreases the compression (adds tension) on the other. As long as the additional tension doesn't exceed the original pre-compression, the concrete member can bear the bending load.

In reinforced concrete, the pre-tension of the steel bars generates a pre-compression in the concrete, allowing it to bear bending loads it ordinarily would not be able to support.

your description on wheel stiffness vs spoke tension is exactly what i concluded some time ago. but then i figured that had to be wrong....here's why. consider a fork spring on a telescopic fork because it easier to see (for me).....it is common for the springs to be preloaded a certain amount. in fact many forks have an external preload adjustment. i can say for sure that more spring preload causes the fork to be stiffer. actually it's not stiffer.....it takes more force to initially start compressing the fork....then of course it compresses according to the spring rate. i think the wheel is the same problem except theres the effect of the opposing spoke (spring)

your description on wheel stiffness vs spoke tension is exactly what i concluded some time ago. but then i figured that had to be wrong....here's why. consider a fork spring on a telescopic fork because it easier to see (for me).....it is common for the springs to be preloaded a certain amount. in fact many forks have an external preload adjustment. i can say for sure that more spring preload causes the fork to be stiffer. actually it's not stiffer.....it takes more force to initially start compressing the fork....then of course it compresses according to the spring rate. i think the wheel is the same problem except theres the effect of the opposing spoke (spring)

Your analogy fails, because a wheel is very unlike a suspension fork.

In the fork, the spring acts to extend the fork, which it does until it reaches a "hard stop" (the fork tops out). As you say, until a bump force exceeds the pre-load, the fork will be very stiff..

However, there is no hard stop on the wheel's rim. It maintains its shape based on the stiffnesses and pre-loads of its structural members (rim and spokes). You can not increase (or decrease) spoke tension until it reaches a "hard stop" that limits its motion. The stiffnesses of these members do not change with pre-load, so while you can change the shape of the wheel by varying the pre-loads, you can not change its stiffness.

Many suspension forks have negative springs, to prevent them from topping out (i.e. to allow sag). If you were to increase the pre-loads equally on both the main spring and the negative spring, would the fork change compressive stiffness? The answer is no. You can change the amount of sag (neutral point) of the fork, but the stiffness of forks with linear springs (coil springs) can only be changed by replacing the springs with stiffer or softer springs.

i looked at the problem as two springs tied together at one end and connected to rigid bodys at their opposite ends and can see you are correct

I guess that's good news. I always thought dual-threaded spokes were stupid (compared to more standard straight-pull spokes).

Does anyone know when the new wheels will be released? I don't see anything new on Easton's web site. Blue sky cycling.com seem s to be the only company that is selling the "new" style wheels, but I'm not sure they are using anything different other than the rim. Any thoughts?