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What is the correct setup? I want to build up a strong training wheelset.

24/28 Sapim Race spokes
28/32 CX-Ray Spokes

What is the right way to understand this notion? In short, does spoke quantity outweigh spoke thickness for a stronger wheel?

Thanks
 

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There are several things to consider regarding the composition of any set of wheels.

In your case, you want a 'strong training wheelset'. It depends on what you mean by 'strong'. If you are a bigger rider and need a sturdy wheel to carry you without having spokes break, then, the larger number of spokes will serve you better than a given type of spoke.

There are other factors to consider here. If this is a 'training' wheelset, then, the aero/lightness of spokes (CX-rays) may not be needed. Also, for a 'training' set I would want to contain cost. The CX-rays cost $2.75 apiece and the Race $0.80. That's over $100 more for the aero/lighter spokes.

I'd suggest that you give everyone here a little more information and let them make specific recommendations for you.
 

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Apologies in advance, I can't be brief in response to questions like this. If you want my super short answer to "in short, does spoke quantity outweigh spoke thickness for a stronger wheel?", then that answer is "yes."

I never ask spoke "meat" to do the job that spoke count should do. A lot of wheels come with really thick fan blade spokes and brutally heavy rims in order to have fashionably low spoke counts. There is absolutely no functional advantage to these, the spokes are aerodynamically bad, and people often notice getting knocked around in cross winds despite the low spoke count and shallow rim.

For a training wheelset, I'd first suggest replacing CX Rays with Lasers in the discussion. CX Rays are about 3x the cost of Lasers at the same weight, and with functionally identical characteristics. If you must have CX Rays, I won't dissuade you, but people often assume that Lasers are a markedly heavier or somehow otherwise inferior spoke to CX Rays, which they aren't.

Strength is an umbrella for a lot of characteristics. Lateral stiffness, you are at a spoke count where increasing spokes has a diminishing effect. More spokes will give you more lateral stiffness, but the rim and hub choices will likely have a greater effect than spoke count in that neighborhood.

Ability to withstand abuse from bad roads, etc will again be a function of rim choice and also build quality. A poorly built 32 spoke rear will misbehave under less strain than a well build 28 spoke rear. A 32 spoke wheel will be more tolerant of a bad build than a 28, but let's not start off with accommodations to unnecessary parameter deficiencies.

Spoke breakage is infinitely more likely to occur from cyclical fatigue than from tensile overload. Lasers/CX Rays are actually stronger in tension than Races, but they have an advantage as regards cyclical fatigue. Line up a Race, a Laser, and a CX Ray, and stand them up vertically. Now push down on the top of each until it deflects in the middle. The Race takes quite a bit of force to bend, the Laser much less, and the CX Ray nearly none. That deflection in essence "protects" the ends of the spoke from harsh cyclical loading. Particularly on non-drive side rear spokes, a spoke that deflects more easily can be functionally infinitely stronger than one that deflects less easily. Spokes almost always break at an end, very very rarely in the middle. This issue is why a lot of builders don't even consider straight gauge spokes, and is also related to ride quality, which is hard to quantify and therefore subject to usually unproductive debate.

If you divide the weight of a wheel by the number of spokes it has, I find I generally prefer riding those wheels with a low quotient. An 800 gram rear with 28 spokes (quotient ~ 28), I will probably like quite a bit. A 1000 gram rear with 20 spokes (they exist - quotient = 50), I will probably hate. This is a concept I've been trying to tune for a while and the rim depth and material factor in there but the general premise is useful.

An additional factor is the "stuff happens" factor. If you do happen to break a spoke for whatever reason, more spokes is beneficial. A few years ago, at the beginning of a long training ride, a team mate broke a spoke on a 32 hole wheel. He broke it off, said "eh, I've still got 31 others," and did the remaining 70 miles without a second thought.

For a training wheelset, I pretty well always advise "rounding up" spoke count if you are between. Depending on your weight and other components selection, 24/28 with Lasers could be overkill. At 165 pounds, a well built low to mid 1500s gram 24/28 wheel set with Lasers and good hubs and rims is a very robust training and cyclocross wheelset for me.
 

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What is the correct setup? I want to build up a strong training wheelset.

24/28 Sapim Race spokes
28/32 CX-Ray Spokes

What is the right way to understand this notion? In short, does spoke quantity outweigh spoke thickness for a stronger wheel?

Thanks
The notion is that the greater the number of spokes the lesser the load (lateral, radial, torsional) each has to carry; the lesser the load, the lesser the imposed fatigue (on spoke and rim drilling) and the higher the spoke longevity and thus wheel integrity.

Similarly, the more elastic a spoke is the more the load is spread between adjacent spokes and the more the rim localized stresses are reduced in proportion to the cross sectional area of the spoke.

My personal view and preference on training wheels is that you can do a lot worst not using butted 14/15 ga. spokes like the Race rather than using them. They are easier to build to a high quality wheel because they don't twist as easy as the thinner or flatter variety and are elastic enough for load dispersion.

For your particular example, I believe the results will be comparable either way, assuming reasonable weight, however you will not realize as much of the aero benefits of the Rays being stacked up on a 28 arrangement.
 

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dcgriz - Excellent points, well stated. My only exception would be that if by "flatter" spokes, you mean bladed spokes, you underestimate how psychotically easy those are to build with. You have basically complete ability to eliminate windup, and a careful builder has like almost infinite resolution in making tiny corrections.
 

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No doubt Dave the more often something its done the easier it becomes. I am assuming the OP is brand new in the wheel building scene and as such I consider the Race easier to start with.
 

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dcgriz - Excellent points, well stated. My only exception would be that if by "flatter" spokes, you mean bladed spokes, you underestimate how psychotically easy those are to build with. You have basically complete ability to eliminate windup, and a careful builder has like almost infinite resolution in making tiny corrections.
yes you can control spoke twist. is it 'easier'? no. it requires a dedicated tool. as dc says below, they're fine for an experienced builder, but i would never, ever, say it's easier to build a wheel w/ bladed spokes.

No doubt Dave the more often something its done the easier it becomes. I am assuming the OP is brand new in the wheel building scene and as such I consider the Race easier to start with.
 

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yes you can control spoke twist. is it 'easier'? no. it requires a dedicated tool. as dc says below, they're fine for an experienced builder, but i would never, ever, say it's easier to build a wheel w/ bladed spokes.
We disagree on that then. I find it dead simple and always have, because you have complete control of the spoke. The elegant version of the dedicated tool costs $6 or $7 and you can make your own with basically anything on hand if you have a hacksaw. No biggie, though.
 
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