How many spokes?

on-yer-bike

What's the advantage of 32 spoke wheels over say 24/20 other than you can still get home if a spoke breaks?

ugo.santalucia

The load is distributed over more spokes, therefore the cyclic stress per spoke is lower.
As fatigue life roughly decreases of one order of magnitude every time the stress doubles, you can expect a spoke in a 16 spokes wheel to last 10 times less than that of a 32...

Also, for a wheel to be stable you need a certain amount of tension... if the tension is spread over 32 spokes, it can be kept lower than saying 24 or 20... this greatly increases the longevity of the rim, as rims also suffer fatigue at the hole, which is proportional to the tension applied at each individual spoke.

There are a million reasons why a 32 spokes wheel with double butted spokes is better than a 24 with chunkier spokes, yet the market has concentrated on the latter approach essentially due to "alleged areodynamic benefits" which are mostly irrelevant and lower manufacturing cost, especially if the wheel can be machine built. 32 spoked wheels at 3 cross cannot be machine built.

gwillis

Your going to have to start charging soon for your knowledge .
Should be nominated for most helpful forum member too .

Btw open pros and 105 hubs still going strong as per your advice Paulo .

on-yer-bike

Is it anything to do with the rider weight? ie Heavier riders need more spokes? Do you ever build wheels with less than 32 spokes? With all these factory built wheels with less straight pull spokes, 32 spokes tend to look a little retro.

ugo.santalucia

on-yer-bike wrote:

Is it anything to do with the rider weight? ie Heavier riders need more spokes? Do you ever build wheels with less than 32 spokes? With all these factory built wheels with less straight pull spokes, 32 spokes tend to look a little retro.

The load is the rider + luggage weight... the better you can distribute it, the longer your spokes will last.
The spoke count is always down to rider weight and use. Some people ride thousands of miles, other keep their "best wheels" for those special days... in the latter case there is no reason to over-engineer... I am not a big fan of 20/24 sets, but some rate a few thousand miles as a proof of robustness and durability... "horses for courses" as they say

on-yer-bike

The reason Im interested in handbuilts is that the rear rim on my 2008 Campag Neutrons is nearly shot as is the freehub and its not economically viable to rebuild them. They havent had that much use but have been used in winter. Im the second owner and the first owner, a 15 stone rugby player kept braking the spokes and I picked them after the second warranty repair as he was fed up with them. No broken spokes for me though.

ugo.santalucia

on-yer-bike wrote:

The reason Im interested in handbuilts is that the rear rim on my 2008 Campag Neutrons is nearly shot as is the freehub and its not economically viable to rebuild them. They havent had that much use but have been used in winter. Im the second owner and the first owner, a 15 stone rugby player kept braking the spokes and I picked them after the second warranty repair as he was fed up with them. No broken spokes for me though.

Those use a radial pattern on the NDS... while this makes the wheel a bit stiffer and increases the NDS spoke tension a bit (always a problem in wheels with Campagnolo freehub, as it will be in DA 11 wheels), it also results in lower lifespan, especially on the drive side, as these spokes cannot share the torsional load with the NDS any longer. of course a strong powerful rider will give those a harder life than you do.
So what to go for? You can probably safely go for a set of 28 holes... the weight saving is around 80 grams over the same set at 32, not impressive. Alternatively you can go for 32 Sapim Laser/DT revolution at the front and pretty much have the same weight of a full 28 set with conventional DB spokes.

I have three sets of self built wheels: 28-32 and 36... while the latter are considerably heavier than the 28 (heavier rims as well) a blindfold test will probably only reveal them in view of the totally different tyre choice

Ultimately, if you are after a modern PRO look, get a set of Cosmic Carbone

huuregeil

ugo.santalucia wrote:

Those use a radial pattern on the NDS... while this makes the wheel a bit stiffer and increases the NDS spoke tension a bit (always a problem in wheels with Campagnolo freehub, as it will be in DA 11 wheels),

Actually, the other way round. Radial NDS drops the NDS tension - you're trading lateral stiffness off with tension, so a heavy rider might also find themselves breaking NDS spokes on such a wheel!

Anyway, otherwise spot on! The only other thing to bear in mind is that lower spoke counts can result in a less stiff wheel, which may be noticeable if you're a powerful rider or carry some load. This is also a function of the rim and hub choice too, so you need to consider the entire package. A well built & well specc'ed wheel should never run into fatigue problems, thus the spoking choice is mainly a function of an appropriate package which includes weight and stiffness. In other words, to answer your question, the advantages of 32 spokes only make sense in the context of an entire package - what you really gain with handbuilts is the possibility to tune the package to your requirements rather than accept what comes off the shelves.

on-yer-bike

ugo.santalucia wrote:

on-yer-bike wrote:

Ultimately, if you are after a modern PRO look, get a set of Cosmic Carbone

I already have some Bora Ultra Ones which are fine for dry racing, TTs and nice summer days. I'm after something to replace the Neutrons that dont weigh a ton but can cope with the roads round here. As you know I was set on Record hubs but now wonder if I should go 28 or 24 spoke which means another brand of hub.

ugo.santalucia

on-yer-bike wrote:

ugo.santalucia wrote:

on-yer-bike wrote:

Ultimately, if you are after a modern PRO look, get a set of Cosmic Carbone

I already have some Bora Ultra Ones which are fine for dry racing, TTs and nice summer days. I'm after something to replace the Neutrons that dont weigh a ton but can cope with the roads round here. As you know I was set on Record hubs but now wonder if I should go 28 or 24 spoke which means another brand of hub.

No... stick to the Record. They have an excellent geometry for low profile rims. They have excellent angular contact bearings, virtually last forever with little or no maintenance. The quick release have internal cam and will last forever. The freehub is well designed and will oulast any other product on the market.
Strangely enough for Campagnolo, they even cost less than the Shimano counterpart!
I have a Campagnolo record front hub dating early 1980s... for the first time this year I decided to open it and grease it... I found out there was no need

Fashion comes and goes, Record is here to stay!

huuregeil

Yup Record are lovely hubs. However, there are other similarly lush hubs with other drillings - e.g. I'm thinking PMP in particular, which in silver ooze Italian style in a way that the old Campag hubs did and the new ones no longer do quite! Superbly engineered too, they are every bit the match of Record and have a range of drillings for not very much more cash (you need to order direct from Italy though).

Depends on your rim choice, mind, and your weight/strength. I'm a relatively strong 75kg and am just building myself a set of Archetypes at 24/28, laser front, laser/comp rear, which I expect will be plenty stiff enough and will come in around the 1500g mark. If you want record (thus 32 spokes) then something lower profile is more appropriate (e.g. DT RR415/465).

drlodge

I've just had a set of hand built made by Harry - Record hubs (32H), Excellight rims, Sapim laser front and race on the rear. Bullet proof, will last for years, pretty light weight and very comfortable.

I reckon a 20 spoke, deep rim wheel would be ever so stiff, and not as reliable.

on-yer-bike

huuregeil wrote:

Yup Record are lovely hubs. However, there are other similarly lush hubs with other drillings - e.g. I'm thinking PMP in particular, which in silver ooze Italian style in a way that the old Campag hubs did and the new ones no longer do quite! Superbly engineered too, they are every bit the match of Record and have a range of drillings for not very much more cash (you need to order direct from Italy though).

Depends on your rim choice, mind, and your weight/strength. I'm a relatively strong 75kg and am just building myself a set of Archetypes at 24/28, laser front, laser/comp rear, which I expect will be plenty stiff enough and will come in around the 1500g mark. If you want record (thus 32 spokes) then something lower profile is more appropriate (e.g. DT RR415/465).

So you wouldnt put 32 spokes on Archetypes? What hubs are you using to get 1500g?

huuregeil

Doh, mis-type! I meant 1600g with PMP (alloy nips), not measured but an estimate. You can put 32 spokes on an Archetype but you might not need to as the extra width means it's stiffer laterally.