ratrod

I have laced up a few wheels, but never with a 4 cross pattern. When I was talking to the LBS the mechanic told me that you need multiple spoke lengths to do this pattern. I understand that due to dish, you may need different spoke lengths for the left and right side of the rear wheel. The mechanic however told me that I will also need different spoke lengths with respect to one side of the wheel and that he didn't know why or how to figure out in advance what lengths. I can't find in any of my books or online a mention of different spoke lengths neccesary for a four cross pattern. Has anyone heard of needing multiple spoke lengths (with respect to one side of the wheel) for the four cross pattern? If so, how I can figure out the other lengths.
Thanks

Al1943

I don't think so but have no experience with 4 X. Have you tried an online calculator like the one at DT Swiss?

Al

Bike_13

Do a google search for spocalc.xls - it's great free spoke length calculator.

mechBgon

Switching to 4-cross won't require two lengths of spokes per side.

supcom

The mechanic obviously doesn't design wheels. However, a 4-cross spoke pattern is not much stronger than a 3 cross, yet suffers from a serious deficiency in that each spoke is probably going to overlap another spoke head. If you ever break a spoke, replacing it may be a real pain. Just something to consider before you buy a bunch of spokes...

Retro Grouch 

I have experience building wheels for tandems. I use 4 cross on 40 spoke wheels and 5 cross on 48 spoke wheels. With fewer spokes at some point the spokes that go in one direction will overlap the heads of the spokes going in the opposite direction and create some unnecessary problems. I generally build 32 and 36 spoke wheels cross 3, and 28 spoke wheels cross 2.

If you think about it, the spokes on either side leave the hub flange at the same angle regardless of whether they face forward or backward. Consequently it's exactly the same distance from the hub flange to the rim. That's independent of the number of spokes.

531phile 

5 cross? whoa. I didn't know there was such a thing.

HillRider

Remember, a 36 hole hub is the minimum for 4X lacing.

DannoXYZ 

Remember also that the crossing only affects torsional rigidity of the wheel. Lateral and vertical stiffness or strength won't be any different.

toomanybikes

In honour of sydney - Rubbish,

One length per side - number of spokes per side must be divisible by 4

ratrod

Thanks everyone for the information. I figured the mechanic was in error.

San Rensho 

He's right, it only affects torsional rigidity. And thats why, if my memory serves me,a 4 cross rear is the way to go because with 4 cross, the spokes are coming off the hub in a perfect perpendicular direction, so that all the drive from the hub gets transfered to driving the rim. I also mirror lace the rear so that the driving spokes are on the inside of the hub, that way the drive spokes are bent the least amount and have less of a tendency to break.

mechBgon

The angle at which the spokes leave the flange is a bit more complex, involving the number of spokes the wheel has. But anyhow, a well-built, appropriately-spec'ed wheel of either design will last until you're sick of it. *glares across room at Cannondale full-tourer, still stuck in 7-speed land by its ca. 1997 wheelset *

Thrifty1

Website for Spocalc spoke length calculator. "Full" version includes good variety of rim and hub data.
https://damonrinard.com/spocalc.htm

Gonzo Bob

Rubbish. You can build a 36 and 44 spoke wheels using a 4-cross pattern. That's 18 and 22 spokes per side which are not divisible by 4.

HillRider

Not correct. The number of spokes per side for cross-laced wheels must be divisible by 2. For radial laced wheels even this isn't necessary. There are several 18 spoke radial laced front wheels available with, obviously, 9 spokes per side.

FarHorizon

Doesn't using a 4-cross pattern reduce the likelihood of breaking a spoke significantly? If the spokes'll never break, who cares if the heads are overlapped? I'm not arguing with you here, I'd honestly like your feedback on these questions. Thanks!

HillRider

No it doesn't. It's a bit easier on the hub flanges since with 36 hole rims, the spokes are almost perfectly tangential to the flange. However, there is no reason it should be easier on the spokes.

These days, spoke breakage using DT, Wheelsmith or Sipam spokes and a 32 hole 3x pattern properly laced and tensioned is so rare as to be a non-issue. The rims will wear through and crack at the brake tracks or pull through at the spoke beds before any of the spokes break. I've had 32 hole 3X wheels last 30,000 miles and be replaced because of rim failure and NEVER broken a name-brand spoke. Worries about spoke failure are a remnant of the old mild steel plated spokes of years ago or the result of very poor lacing technique.

In fact, the durability of modern spokes is what makes the current crop of very low spoke count boutique wheels possible.

dooley

I use 4x wheels on my 48 sole bmx wheels, and they are definitely tougher than 3x provided the hub flanges are big enough for the spokes not to cross the spoke heads. However when you start to factor in dishing then I'd be far less sure of the advantages.

Jason Curtiss

I have found that 4-cross wheels provide a slightly more compliant ride than say 3-cross. So, when I lace up a wheel for use on a touring bike, I use a 4-cross spoke pattern.

Jason

HillRider

This myth just won't go away.

Timmi

Could you please explain why you say this?

I will explain why I never disputed this "myth", as you call it:
I do believe that a longer elastic can be stretched a longer distance than a shorter one (before breaking, and return to their original shape (please let me know if you disagree with this)... just like spokes.
Also, being beyond tangential, should also allow for more give-and-take in the wheel than precicely or pre- tangential.

Timmi

Some resources for those landing here:

Sheldon Brown's page on lacing spokes
Wheelbuilding

3 good online spoke length calculators:

simplest:
Spoke Length Calculator for Bicycle Wheels

with flange distance from center:
Spoke Length Calculator

(auf Deutsch) with flange distance from end:
Genaue Berechnung der Speichenlaenge

fietsbob

A 5 cross in a 48 spoke is like 4 cross for a 36 spoke .. The 1st cross is the spoke on the opposite side of the hub flange,
headed to the opposite side of the Rim.

I have Built several 4 cross wheels . my drum brake winter bike wheels are 4X

My Campag Hi-Low rear hub is 4x on the NDS , small flange,& 3 cross DS, to the large flange ..

FBinNY 

First of all, you need at least 36 spokes to do 4x lacing. If you try to 4x on 32 or fewer holes the spokes would pass beyond the diameter on the hub, and leave the flange on a secant instead of a near tangent.

But if you have 36 spokes 4x is actually easier than 3x because it's a true tangent, and flange size has just about zero effect on spoke length. This was always nice as a builder because it required few spokes in inventory to cover a variety of hubs.

So, I suspect that the mechanic was speaking purely from ignorance, and projecting issues relating to something which was foreign to him.