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Russian Troll Farmer
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I'm no engineer but if they can have an unproven opinion then so can I. I would think that the "elasticity" of thinner gauge spokes like CX-Ray and Laser would lead to LESS spoke hole cracking, not MORE. It's been long opinionated that straight gauge spokes would tend to absorb less shock and therefore transfer it to the rim and hub flanges.
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I AM an engineer, and I'd like to add my $.02 to this highly hypothetical discussion. Yes, a thinner spoke can cause fatigue at the holes. Fatigue is caused not by tension (that would be more ductile failure), but rather by the number of stress CYCLES of certain tension limits. If the thinner spoke is more elastic, the tension cycle would have greater limits, and will cause fatigue failure quicker than a spoke in which the stress cycle has limits which are less severe. Also, if the spoke goes completely slack during the cycle (as a leading spoke during a heavy climb might), then you will also be adding cyclical impact from the nipple seats into the equation, which will hasten fatigue failure measurably.
 

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A wheelist
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I AM an engineer, and I'd like to add my $.02 to this highly hypothetical discussion. Yes, a thinner spoke can cause fatigue at the holes. Fatigue is caused not by tension (that would be more ductile failure), but rather by the number of stress CYCLES of certain tension limits. If the thinner spoke is more elastic, the tension cycle would have greater limits, and will cause fatigue failure quicker than a spoke in which the stress cycle has limits which are less severe. Also, if the spoke goes completely slack during the cycle (as a leading spoke during a heavy climb might), then you will also be adding cyclical impact from the nipple seats into the equation, which will hasten fatigue failure measurably.
I won't insult you by arguing engineering principles with you even if I truly think we're talking minuscule differences here between the effects of one type spoke and another slightly heavier swaged spoke. But what kind of a marketer says stuff like they did in public? Even if they were 100% right.
 

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Mike: Talk to Brandon about the AForce Al33 Rims. He suggested I try them when I wanted to build new wheels about a year ago. WI T11s and Cxray Spokes. Couldn’t be happier with the results.
 

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I AM an engineer, and I'd like to add my $.02 to this highly hypothetical discussion. Yes, a thinner spoke can cause fatigue at the holes. Fatigue is caused not by tension (that would be more ductile failure), but rather by the number of stress CYCLES of certain tension limits. If the thinner spoke is more elastic, the tension cycle would have greater limits, and will cause fatigue failure quicker than a spoke in which the stress cycle has limits which are less severe. Also, if the spoke goes completely slack during the cycle (as a leading spoke during a heavy climb might), then you will also be adding cyclical impact from the nipple seats into the equation, which will hasten fatigue failure measurably.
I would fully agree with your argument if there was greater elasticity in the CX Ray spoke over say a Leader or any other straight 14 gauge spoke. However that is not the case (see tensile strengths listed below). Even though the CX Ray lacks girth which will lead to more lateral movement which supports your conclusion of movement at the nipples work hardening the rim (just that the movement is not generated by elasticity). This still does not support Pacenti's claim that the CX Ray spokes shouldn't be used while the D lite's are the preferred spoke? The D Lite has a lower tensile strength i.e. greater elasticity and has a 0.05 greater amount of surface area (trivial) than the CX Ray which means it would not resist later forces any significantly better. That would also suggest that Pacenti does not want there rims built with Lasers either. Then there is also the argument that Hed Belgium's and Easton 90 rims that share similar dimensions also shouldn't be build with the fore mentioned spokes while empirical evidence points to the contrary.
At this point I am officially calling BS to Pacenti's argument. That being said, unless they retract there claim no one should build with the CX Ray spokes on there rims. Anyone that does, rides at there own peril as Pacenty clearly is stating that they take no liability for any harm that befalls someone that is harmed due to there rims failure while using the CX Ray spokes. What a shame!

Sapim Leader 1180nm tensile strength 2.0 gauge (greatest elasticity)
Sapim Race 1300nm tensile strength 2.0 x 1.8 x 2.0 gauge
Sapim D Lite 1370nm tensile strength 2.0 x 1.65 x 2.0 gauge
Sapim CX Sprint 1430nm tensile strength 2.0 x 2.25-1.25 x 2.0 gauge
Sapim Laser 1500nm tensile strength 2.0 x 1.5 x 2.0 gauge
Sapim CX Ray 1600nm tensile strength 2.0 x 0.9-2.2 x 2.0 gauge (least elasticity)
 

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These new Pacenti owners are jokers with this and a bunch of other stuff they've done (which isn't for me to comment on). At one time, Kirk P told us that we were his biggest independent wheel build customer. For all I know there are a dozen others he told that to, as honesty wasn't exactly his strongest suit either, but it gives some idea of how much we were doing with Pacenti rims. And we sure had our share of problems with the rims, though not to the percentages that others had.

When the new owners took over they reached out and said we'd love to have you back, tell us what it will take to get your business, blah blah blah. For once in my life I said exactly the right thing in that situation (normally I'm way too charitable) and told best of luck your brand is dead to me we have no interest. Boy am I happy with that choice.

We've built thousands of aluminum wheel sets with CX Rays, as have many many others who no doubt build WAY more wheels than we do (Chris King, for one). I can count on one hand the number of rim failures we've had with non-Pacenti alloy rims and still have a finger or two left over. That's, um, not the case with Pacenti. There are too many good rims on the market to waste time with jokers.

Hi Mike T!
 

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A wheelist
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At this point I am officially calling BS to Pacenti's argument. That being said, unless they retract there claim no one should build with the CX Ray spokes on there rims. Anyone that does, rides at there own peril as Pacenty clearly is stating that they take no liability for any harm that befalls someone that is harmed due to there rims failure while using the CX Ray spokes. What a shame!
I think it's best that everyone forgoes P-word rims rather than CX-Ray spokes. IMO P-word rims will soon go the way of the do-do bird and we'll all keep on merrily using CX-Rays on our rims of choice. And with zero problems.
 

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A wheelist
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Mike: Talk to Brandon about the AForce Al33 Rims. He suggested I try them when I wanted to build new wheels about a year ago. WI T11s and Cxray Spokes. Couldn’t be happier with the results.
Thanks Brad. I was going to contact Brandon to see what he recommends. In the meantime, I'll check those rims out and read up on them.
 

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This thread is like a family reunion with Mike T.
Are u going to announce another retirement? Or are u officially retired after this thread?

RC
 

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lower tensile strength i.e. greater elasticity ...

Sapim Leader 1180nm tensile strength 2.0 gauge (greatest elasticity)
Sapim Race 1300nm tensile strength 2.0 x 1.8 x 2.0 gauge
Sapim D Lite 1370nm tensile strength 2.0 x 1.65 x 2.0 gauge
Sapim CX Sprint 1430nm tensile strength 2.0 x 2.25-1.25 x 2.0 gauge
Sapim Laser 1500nm tensile strength 2.0 x 1.5 x 2.0 gauge
Sapim CX Ray 1600nm tensile strength 2.0 x 0.9-2.2 x 2.0 gauge (least elasticity)
Richard, this is mistaken. Less tensile strength does not mean more elasticity. Tensile strength measures breaking point and elasticity measures how much something stretches and still be able to snap back to original. For example, a suspension spring is both very elastic and also has a very high tensile strength.

The narrow area of a CX-Ray does in fact make it stretch more than a thicker spoke. So a CX-Ray is more likely to rub the rim on the brake pads than a thicker spoke. Sapim themselves advertise the flexibility of CX-Ray and the relative stiffness of CX-Sprint. https://www.sapim.be/spokes/aero/cx-sprint

https://www.sapim.be/spokes/aero/cx-ray

 

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Burn baby, burn.
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Discussion Starter · #31 ·
Well I got my wheels back from my wheelbuilder (I just did not have the interest in building them myself, too many other issues including unemployment on my mind at the moment).
He agrees with everyone else here that this failure had nothing to do at all with the spokes (and in fact kept the CX-Rays , which he said were still in perfect condition).
Maybe I will get a chance to ride them tomorrow and experience the ride improvement that these D-lite spokes will supposedly provide for myself.
The Pacenti stickers are also a PITA to remove. :(
 

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wheelbuilder
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The main reason I have heard is that sales have been too slow lately, and not just for BHS. Which is a shame because it is one of the best alloy rims out there. I consider it in second place behind HED, with HED mainly winning on style. I prefer the asymmetrical design because spoke tension really is better.
I strongly urge you to look into Boyd and Astral for alloy rims. Both have been serving me well of late. Hed and Easton are still top choices as well. Those 4 brands all have rims that have been around long enough to have a clear track record and build up extremely straight and true with even tension.

For those that prefer, Astral rims are the only ones mentioned above that are made here in the USA.
 

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I'm a builder, too...I have built a fair number of Pacenti rims. Mostly Forza disc, some Brevets, and some of the other disc rims a few years back.

I'm no engineer, and don't have as many wheels under my belt as others, but this CX Ray thing does sound like total rubbish. Common sense? I can't recall if I've built any Forza's with CX Ray, but may very well have, and also likely others than the prescribed D Light.

Don't want to be a thread hi-jacker, but found my way here as a result of having my own warranty issues with Forza rim brake rims. What I am finding out after already replacing a rim once, and now offered a third, is that these rims are not being made to uniform width - resulting in untruable wheels which cause brake pulsing because of their variable width.

The greatest difference seems to be in the first rim, and that difference is .43mm.


This you can see is occurring about 6 spoke holes distance apart. Thought some here would find this interesting.
 

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Burn baby, burn.
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Discussion Starter · #34 ·
Rode the new rear wheel for the first time last night.
I don't feel any difference in ride quality.
But at least there is no cracking around the spoke holes I guess?
 

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'brifter' is f'ing stupid
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I'm a builder, too...I have built a fair number of Pacenti rims. Mostly Forza disc, some Brevets, and some of the other disc rims a few years back.

I'm no engineer, and don't have as many wheels under my belt as others, but this CX Ray thing does sound like total rubbish. Common sense? I can't recall if I've built any Forza's with CX Ray, but may very well have, and also likely others than the prescribed D Light.

Don't want to be a thread hi-jacker, but found my way here as a result of having my own warranty issues with Forza rim brake rims. What I am finding out after already replacing a rim once, and now offered a third, is that these rims are not being made to uniform width - resulting in untruable wheels which cause brake pulsing because of their variable width.

The greatest difference seems to be in the first rim, and that difference is .43mm.


This you can see is occurring about 6 spoke holes distance apart. Thought some here would find this interesting.
Interesting...and definitely not confidence inspiring.
 

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Banned Sock Puppet
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Fool me once, shame on you. Fool me twice, shame on me.

OK, I'm late to the party here, but really, it should be perfectly obvious to any reasonable person at this point that Pacenti cannot be trusted. After all the reports on the SL23, with so many other great quality rims out there, why would anybody jump in the water again? And what does Pacenti do? They try and blame CX-Ray spokes when there have never been reports of failures on any other rims due to using these?? I agree - total BS.

That being said, a ridiculously low spoke count paired with a heavy rider WILL challenge even the most robust rim on the market. Looking carefully at the pic of the OP's rear wheel, it looks like a 28 spoke, so it's a reasonable spoke count. We don't know the OP's weight though.

Hi Mike!
 

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So definitely not a clyde and not at a weight that would be stressful on wheels.
My question is, how many lbs. or kilos. does a clyde make?

85kilo\187lbs is not a small man. I'm 6'1" and about 185lbs and consider myself a "large" cyclist.
 

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My question is, how many lbs. or kilos. does a clyde make?

85kilo\187lbs is not a small man. I'm 6'1" and about 185lbs and consider myself a "large" cyclist.
You are tall, but not what I would consider "large" except maybe within the range of elite racer cyclists who look like all arms and legs. Your weight is at the high end of normal for your height. At 5'10" and 170lbs, I fall into the same 24-25BMI range as you do.

I generally consider "clyde" to be 250lbs or more and someone who is 200 to 250lbs to be a "baby clyde".
 
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