[Closed] Black spokes are weaker...

Bollox to him. Find someone else.

I've heard that before a few times from big al at wheelcraft.

people say it but it is BS

Also, red bikes are faster.

All the hot girls wear glasses

What makes them black?
Does the surface treatment cause a 'weakness' in the material?

So it's possible.

I personally dont like them... IMO a nice set of SS spokes makes a wheel look nice.

[quote=richmars ]What makes them black?
Does the surface treatment cause a 'weakness' in the material?
So it's possible.
It's also possible that the surface treatment strengthens them. Or indeed makes no difference whatsoever.

Expensive wine or whisky is the nicest.

It's also possible that the surface treatment strengthens them. Or indeed makes no difference whatsoever.

Which is why I said it's possible, which is true.

It used to be true of cheap black spokes, but decent ones are no worse than silver. He'll be telling you plain gauge builds a stronger wheel than double butted next......

I meant to add that they will look untidy after a short while cos the black will wear/scratch off.

As pp quality black spokes are fine Dt, Sapim etc
And the Finnish is very good and very duarable
Cheap black will wear off and IMO cheap spokes are a waste of time what ever the colour

I got a wheel built for touring. It had black spokes. About a quarter broke, one at a time as I was riding along. The plural of anecdote isn't data though.

I've build many hundreds of wheels using black and silver spokes and have never had a comeback from either of them for breakage.

That said I also use Sapim/Dt Swiss spokes and not the cheap junkers so distributors sell.

From a great deal of personal experience, I call BS.

And the Finnish is very good and very duarable

?

[img] [/img]

One of my flat blades on my new MavM40C's broke, took 4weeks to get a replacement wheel (under warranty from Mav) cos they didn't want to replace just one spoke.

They are black 😆

Total bobbins. There may have been some truth in it once - in that low-quality spokes were sold for more by dint of the fact that someone had powdercoated them black.

If you use quality spokes & it doesn't matter what colour they are.
I once had the pleasure of building a wheel with splatter & rainbow anodized Ti spokes and within the confines of the snowflake pattern, it was ace.

Built most of my wheels with black and it's yet to rub off even on wheels that are years old

Cheapo crap black spokes are supposed to be slightly weaker, but tbh I haven't yet found out why.

Talk to the decent spoke manufacturers (DT or Sapim IMO) & they'll both tell you they're as strong as their silver version.

Big Al quotes some nonsense about the stove enameling process weakening them. In reality, he's a stubborn, pompous old arse. Good wheelbuilder though. 😀

If Big Al says so good enough for me, whether fact or a Big Alism.....

I once inherited a set of black spoked wheels originating from a Speccy Enduro. They snapped regularly. More than than any other wheels I have ever owned.

Coincidence, or mysteriously linked?

Total BS as long are you are talking 'quality'spokes...

For anyone that has had a wheel built with black (or silver) spokes that has broken a number of spokes, either your wheel builder has used shit spokes or is just a shit wheel builder !

@waderider. Perfect example of badly built wheel..I had to warranty numerous units of those enduro wheels which involved specialized paying us to rebuild with DT Swiss spokes and brass nipples

Big All has built two sets of wheels for me using silver spokes and I've never had any issues with them

esher shore - Member

For anyone that has had a wheel built with black (or silver) spokes that has broken a number of spokes, either your wheel builder has used shit spokes or is just a shit wheel builder !

In my case I think installing a Saint mech into it at 30mph had more to do with it

Mine are black, and made from Zircal, does that mean I'm gonna die 😕

It's bollocks. DT are not stove enamelled, they're electro plated. DT say this makes them more ductile, so if anything they'd be less liable to breaking.

I'd imagine Sapim use the same process, but the cheap OEM ones are painted. And pish.

You will only die using those spokes IF the Moon is on its third phase AND if a virgin chops the head off a chicken whilst stood on one leg

It's BS but came about from some cheap, black spokes that were used on bikes (Specialized spring to mind but there were several other brands) in the late 90s/early 00s which did indeed have a short life. You could usually spot them as they were a sort of matt, slightly rough finish.

Decent black spokes (DT, etc) are fine.

I've heard this one before and just assumed it was the cycle industry picking up on hydrogen embrittlement which can occur when you Zinc plate steels. It [U]Can[/U] affect ductility and tensile strength of steels and it's why many industries now avoid using BZP fixings in any important applications...

"Black plating" of steels is is typically done by applying Zinc Plating and then Black Chromate or Black Passivate.

The EU isn't keen on Chromate as it's carcinogenic, so your black DT or Sapim spokes are more likely to be Black Passivated, which generally offers less corrosion protection...

Stainless steel is betterer...

Zinc and black is not colour fast so i'm pretty sure that's not the process they use. You would pretty quickly have greenish brown spokes, probably black on stainless, it's just controlled oxide onto the spokes, pretty simple to do and purely cosmetic.

I've heard this too and have always assumed that it was either
a) something that might have had something in it a while ago (as people have suggested above) or
b) one of those things that might be sort of true in some hypothetical scenario but in practice will never make any difference.

If that's the case then I stand happily corrected, I wasn't really aware of options for colouring stainless, so embrittled, plated steel was the only "Science based explanation" I could think of...

I've learned something useful today, had a quick look at the BSSA site and a linked Euro Inox document and yep, 5 - 30 minutes in a sodium dichromate bath at ~400*C and you've got black stainless steel... Nice!

that sounds quite high, we run at 121-127DegC. For bolts and stuff that's a low grade stainless we just give them a quick etch to remove the chrome from the surface and then whop them in till they go black. Some higher grades may require blasting before hand though, you need to get through the passivated surface.

He'll be telling you plain gauge builds a stronger wheel than double butted next......

Oh go on then... Why is this wrong?

Double-butted spokes do more than save weight. The thick ends make them as strong in the highly-stressed areas as straight-gauge spokes of the same thickness, but the thinner middle sections make the spokes effectively more elastic, allowing them to stretch (temporarily) more than thicker spokes.
As a result, when the wheel is subjected to sharp localized stresses, the most heavily-stressed spokes can elongate enough to shift some of the stress to adjoining spokes. This is particularly desirable when the limiting factor is how much stress the rim can withstand without cracking around the spoke holes.
S.Brown

You will only die using those spokes IF the Moon is on its third phase AND if a virgin chops the head off a chicken whilst stood on one leg

I need some clarification, is that the virgin or the chicken standing on one leg, I need to be sure...

Also, is the geographical location of the virgin and chicken relevant, ie: if I maintain a sufficient distance am I safe?

My guesstimate is that the rise in popularity of black spokes has ran a parallel course with that of the greater influx of cheaper far eastern spokes and that cheap spokes will be equally shoddy in silver ...

Oh go on then... Why is this wrong?

In a nutshell, because DB spokes stretch more before they break. PG might be a tad stronger (it's not much if they are and Sapim say their DB spokes are actually stronger)
Under load this allows a spoke to stretch and transfer it's load to neighbouring spokes rather than snapping or transferring it to the rim or hub. PG builds a stiffer, more brittle wheel, whilst DB produces a more resilient, longer lasting wheel.
DB is also easier to build and true.
The only reason to use PG spokes is cost. Every text I've read from any wheel builder says the same thing.

That's not strictly true though is it.

What a butted spoke gives you is a reduced cross section at the mid point, so what you are describing is actually a "Weaker" structural element, if the same loads is applied over a reduced sectional area (per spoke) this means greater tensile stress on the mid point of a butted Vs PG spoke...

That slight reduction in cross section is intended to allow this of course so that the butted spoke is operating more in its elastic range (assuming materials and pre-load are the same), effectively the margin to failure is less, for a butted spoke...

Obviously the spoke is't the only component under load in a wheel, it is of course under tension, butting is partly about tuning the component geometry to use more of the materials elastic properties.

Strictly speaking a PG spoke is stronger, it deflects less under a given load and requires a greater tensile load to cause permanent deformation, but this of course increases the chances of damage elsewhere in the wheel, like spoke holes or nipple threads...

Personally, I would find someone who I trust to build my wheels and then go with their advice.
I've done this on the last few builds (against what I thought I wanted) and have been very pleased.

Strictly speaking a PG spoke is [s]stronger[/s] stiffer

FTFY

Alright how's this:

Strictly speaking a PG spoke is stronger AND stiffer,
This does not, however, translate directly to a stronger wheel...

Better?

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🙂

DB are better. End of story 🙂

DB are better. End of story

In black or silver? 🙂

What's the main cause of wheel failure? Broken spokes, cracked eyelets or bent rims?

I suspect the latter is a major cause certainly. A PG spoke would stretch less, and hence the rim would move less for a given side impact, and hence would require more force to move the rim past the limit of elasticity. A PG laced wheel would therefore be less likely to become tacoed.

No?