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• #1327
Meh.
I thought it was a decent explaination of why the resistance to twisting would be the same, providing the total spoke tension was the same.
If you do a quick spoke calc. You'll find roughly a 1% difference in spoke length for 24 vs 28 spokes. As this is your only varible when keep rim, and hub dimensions constant. Its pretty clear that bracing angle isnt going to change much.
Ignore me, I'm in one of those moods.
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• #1328
was thinking of upgrading to these:
**Mavic Open Pro on Dura Ace 7800 - the low profile will help with my hill climbs but any opinion on are they good value, will they last, good for all year riding? Will be doing the usual sportives and some racing
Currently running campagnolo khamsin for winter training (and the fact they seem bomb proof) and was looking to upgrade to Zondas/Fulcrum 3's for the upcoming season but after seeing the above am in a dilemma.
any wiser person able to impart some wisdom would be great.
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• #1329
I've got three sets of wheels from him. None are 36h.
The commuter does use cheap Formula1? rims but they're tough as nails.None of this commuting-on-carbon buyer bollocks.
Ner ner ni ner ner to you to.
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• #1330
Ignore me, I'm in one of those moods.
Best way to increase bracing angle is to get a deeper rim. Which would also need less tension, because the deflection would be less. Unless you want the aero properties, I doubt thats needed for a svelte* type like yourself though.
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• #1331
Ner ner ni ner ner to you to.
I was referring to an earlier post today from Hovis you massive buyer.
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• #1332
Best way to increase bracing angle is to get a deeper rim. Which would also need less tension, because the deflection would be less. Unless you want the aero properties, I doubt thats needed for a svelte* type like yourself though.
No, I'm not really interested in 1W gains @ 25mph or whatever. And I prefer a little vertical spring in my rims. It's exciting.
currently trying to regain svelteness
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• #1333
i) 24h 2x rear, better bracing angles
ii) 28h 2x rear, more spokesAssuming all else the same, which will resist twisting forces better, or is it inconsequential?
(maybe this should be in the wheelbuilding thread, but I think that should just be merged into this thread anyway; meh)
By my rough sums, more spokes just beats better angles in this case. The 28 spoke option will transmit the same torque with a 5% smaller shift in spoke tension.
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• #1334
But if your spoke tension is rim strength limited, and you're able to put 14% more tension on the 24 spokes that would give you more margin against spokes going slack under torque, and make that the better choice.
I doubt rim tension budgets really are constant though. It has to be harder for a rim to withstand more concentrated forces, so you'll get less than 14% more tension with the reduction in spoke count, making the whole thing more of a toss-up.
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• #1335
sorry
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• #1336
It certainly sounds interesting, although I'm not sure it is.
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• #1337
By my rough sums, more spokes just beats better angles in this case. The 28 spoke option will transmit the same torque with a 5% smaller shift in spoke tension.
BMMF is pretty light though. So thats a 5% increase the wheel could easily cope with.
But if your spoke tension is rim strength limited, and you're able to put 14% more tension on the 24 spokes that would give you more margin against spokes going slack under torque, and make that the better choice.
I doubt rim tension budgets really are constant though. It has to be harder for a rim to withstand more concentrated forces, so you'll get less than 14% more tension with the reduction in spoke count, making the whole thing more of a toss-up.
I think the outcome is the same. If your weight, and component choice allow you to add 14% without stressing anything. Then cool. If not add spokes, or change components.
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• #1338
I'll double check with the builder in the end. Going to get someone else to do it this time as it'll be a 40th birthday related treat.
I may only be 65kg, but don't forget the awesome power I deliver out of the saddle. People have said they can see the Earth being deflected from its axis as I accelerate away from them.
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• #1339
I offset the awesome power with the souplesse.
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• #1340
People have said they can see the Earth being deflected from its axis as I accelerate away from them.
Yeah you should stop wearing white bibs in the wet.
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• #1341
Thanks. Thanks for nothing.
Genuine lol in a quiet cafe, got some strange looks. Thanks for nothing..
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• #1342
I'll double check with the builder in the end. Going to get someone else to do it this time as it'll be a 40th birthday related treat.
I may only be 65kg, but don't forget the awesome power I deliver out of the saddle. People have said they can see the Earth being deflected from its axis as I accelerate away from them.
Is that what it is? I had always assumed it was my tiny world being crushed by your awesome power.
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• #1343
I've got my pressing reasons, thanks, and a whole heap of experiences with a veritable plethora of build specs in a wide array of riding conditions, so kindly keep the endlessly reiterated conservatism to yourself.
If 24 is, in your mind, reliable for a recreational rider may I suggest then for the more "advanced rider" of good taste and a whole heap: 12 spokes. A number of races have been won on Campa's 12 spoked boutique wheels so a careful builder should be able to do better.. 10 spokes, anyone?
Call it "conservatism" or not a good reciever of marketing wisdom but.... being tained by science and engineering I think looking at the results of models and testing is--- in addition to field experience--- of merit. Here its been found that the impact of spoke count on bicycle aerodynamics--- its a bicycle+rider that is of interest and not a lone wheel--- is not great as was held in the 1960s and 1970s when these were considered the "special weapons" of speed. Just as we found many of the "aerodynamic" bicycle parts--- oh so popular in the 1980s--- were without tangible merit beyond placebo effects, ultra-low spoke count wheels (not unlike the "Drillium" fashion of the day) do provide safety issues. I've been out of the testing loop for a few years now but when we tested wheels we found that rim, hub, fork, seat-tube and chainstrays were of higher order significance.
So how much energy is saved by selecting something like CX-Rays over standard spokes? Have less spokes? The question is: at what speed? At speeds of 50 kmh reducing spoke count and using different shapes of spokes can amount to several watts-- spoke shape alone can amount to as much as 1 watt. At 30 kmh it is a lot less, typically (using the same rim and hub design) under 5 watts at the extreme--- and often just 1-2 watts. Alone changing ones own position on a bicycle @30 kph can amount to as much as 50 watts (hands on handlebar tops versus optimized aerodynamic position). By subtile changes in position even on the drops one can measure as much as 10 watts difference @30 kmh. At 50 kmh (where it really matters) the differences are significantly greater. Position is, of course, a bit complicated since one needs to find an optimum between aerodynamics, power and efficiency. Its also complicated by the observation that the greatest aerodynamic and strategic benefit is to "suck someones wheels". The advantage of drafting is ENORMOUS. Interestingly the effect of wind resistance in the pack is different than being at the head--- wheels and frame interaction become more and rider position less important. -
• #1344
Whatever. You've made your position clear already. Perhaps you could reinforce it in a more subtile (sic) manner from now on, rather than with another drab soliloquy.
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• #1345
I think you meant tl;dr.
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• #1346
Who is this EdwardZ chap and where the fuck did he come from?
Sometimes I think he is a troll, sometimes I think he might be smart, but I swear half the shit he comes out with is just waffle/nonsense.
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• #1347
He somehow made me look rational and informative...
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• #1348
I wouldn't go that far.
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• #1349
Don't exaggerate, people might think EdZ is an EdS sock puppet put up to make you look good.
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• #1350
The last word on spoke counts..
I've got my pressing reasons, thanks, and a whole heap of experiences with a veritable plethora of build specs in a wide array of riding conditions, so kindly keep the endlessly reiterated conservatism to yourself.