dabac

Hi guys,
I'm about to swap out a damaged rim on a old Mavic Ksyrium Elite, and got to thinking about the spoke pattern. The wheel is built with spokes crossed(of course!) but the spokes aren't interlaced at the cross.
Is there some sort of exotic reason for not interlacing bladed spokes in a wheel of this type?
Would there be anything to gain by interlacing when I have the wheel apart anyhow?
Anything to lose?
Or should I just leave well enough alone?

cycle_maven

I'd just leave well enuf alone- If the spokes on my K-E's are any gauge, then there's quite a gap between the crossing spokes, and you'll have to bend the spokes at the junction to cross them. I don't see any advantage in doing so, especially since the spokes don't touch.

That's a great question though... why weave the crossing spokes on a normal wheel?

noglider 

It seems to me that interlacing them causes them to share tension, which would be a good thing. Mavic may have a reason for not doing so, and they may not, but given that it's an unusual design to start with, I would also leave it as it is.

Trakhak

Interlacing was invented in the days when lower-grade steel was used for wheel building and spoke breakage was taken for granted. The hope was that interweaving the spokes would lessen the likelihood of a broken spoke flying sideways and causing more damage. Or maybe it's just that someone realized it could be done and thought it looked cool. Same thing with tying and soldering spokes, although there's at least a benefit there, in that a broken spoke has nowhere to go.

Jobst Brandt, in his book The Bicycle Wheel, seems to have proven that tying and soldering has no effect on wheel stiffness or strength and that merely crossing the spokes cannot increase stiffness or strength either. I'll have to take his word for the accuracy of the equations he used to produce his results, but his myth-debunking arguments seem sound.

As a side note, I die a little inside every time someone writing about his wheels has to use the word "laced" about a hundred times: "I used to have a set of MA-40s laced to Suntour Superbe hubs, but now I have a pair of Arayas laced to Campy Tipos." Like guitar guys droning on about having a Les Paul "loaded with" Seymour Duncans.

dabac

Well, I built a non-interlaced wheel once. Based on that admittedly modest amount of experience I'm not particularly keen to do it again. What'd happen was that the spokes would start to vibrate during fast descents. Quite unpleasant. There was no mistaking the noise, and I do think I could feel the vibrations all into the bike.

Then again that was a 36H in 3X with round spokes, maybe bladed spokes will do better?

There's quite a distance from the hub to the intersection, and the spokes are bladed, so I'm not concerned about the bend as such - if I decide to interlace.

AEO

ksyriums are the ones with aluminum straight pull spokes, correct?

They're probably not designed to be bent, considering aluminum is not very keen on being bent.


There is a rule about fixing something that isn't broke.

FBinNY 

Non-interlaced wheels are torsionally stiffer than interlaced wheels, because there's no tension shift happening. It's better suited to rear track wheels for sprinting, where the rider wants the max response to hard bursts of max torque. IME it interlacing seems to do a decent job keeping lighter rims true, for a variety of reasons.

OTOH if using carbon spokes, interlacing can cause serious problems by introducing flex and a bending moment at the point of cross. Depending on the properties of the spoke this can be an issue (I don't know for a fact either way, but expect it would be a serious issue for hollow carbon spokes).

My advice, is to assume that Mavic's engineers had reasons for how they laced their wheels and follow suit.

BTW- this should be SOP for any time you rework an engineered item. Unless you have solid knowledge of how and why it's done, and why you'd change it, then best practice would be to follow the lead of the presumably more knowledgeable original builder.

noglider 

FBinNY, when I rebuild wheels on English 3-speeds, I interlace the spokes. I figure they didn't do it merely because the advantages hadn't become apparent by then. Do you think I'm un-engineering something?

FBinNY 

I didn't say you should never change anything, only that you shouldn't change anything without a reason, and knowing the implications of your change.

BTW- Your older 3 speed wheels, and many OEM wheels aren't interlaced for a very simple reason having nothing to do with evolving knowledge. Interlacing slows down the build process so not doing so saves money. The engineers at Raleigh probably decided that the mechanical difference was marginal given the purpose of the bike, and opted to keep costs low. Cost and saving a few seconds in lacing time aren't an issue for you so there's nothing wrong with changing it.

dabac

The wheel I'm referring to is fairly old, probably from 2005 or so. Crossed straight pull steel spokes.