# 24" Wheel Build - 2x or 3x spoke lacing



## onetothepowerofn (Jan 24, 2005)

I am in the process of building my son a set of 24" wheels using Hope Pro 2 hubs and most probably, Velocity Aeroheats. I am currently calculating the spoke lengths and am wondering whether I need/should go to a 2x or 3x cross spoke lacing pattern. Note that the bike will have hydro discs front and rear.

I figure that wheel stability won't be an issue, due to the compact 24" diameter and rider weight (only about 55lb). As I am trying to keep the wheels as light as possible, I figured going to a 2x Cross pattern would be ideal. Can anyone comment on this? Have you found that 2x Cross is sufficient or should I just stay on the safe side and build with 3x Cross? That said will a 3x Cross pattern fit on such a small wheel (I know that my wheelbuilder wasn't able to use 3x on our last 20" build due to the small diameter).

Any input or info would be much appreciated - thanks! :thumbsup:


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## GrayJay (May 16, 2011)

Either 2x or 3x will be fine, 24" wheels definitly can be laced as 3X without problem but 2x will also work fine, just avoid radial lacing if using disks. 
How many spokes/holes are you planning for the build? Using the only available (heavy) rim extrusons designed for adult strength wheels, for a kid bike you can safely drop the # of spokes and still have a strong (and lighter) wheel. Symetrical patterns of 12,18,24,36 spokes are possible from using 36 hole rims/hubs or 16, 24, 32 from using 32 spoke hubs. See my recent 24" wheelset build of 12/18 spokes at;
http://forums.mtbr.com/families-riding-kids/novara-pixie-20-project-853041.html#post10746706


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## TigWorld (Feb 8, 2010)

Depends on the number of spoke holes. For 32h in 24" with Aeroheat's I went with 3x as the spoke length will be a little easier to find (eg. you can get DT Comps in the required length). But, if you can get the spokes you want in 2x length, then go for it. If 28h then go 2x. 3x, 28h and 24" rim = slight possibility of spoke crossing at spoke head - depends on your hub flanges.

Building light in 24" is difficult because of spoke availability. I could only get straight-gauge in the lengths I needed. Even that was so painful I decided to get myself a spoke threading machine for my next 24" build.

GrayJay's asymetrical / reduced spoke count approach is also a good one. Dropping spoke count is a good way to say weight given the difficulty of getting lightweight short spokes.


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## onetothepowerofn (Jan 24, 2005)

*Thanks for the feedback!...*

....The Hope Pro 2 hubs I am using are 28hole, which should make a good start to a nice light wheel. I just got a confirmation from the DT-Swiss factory (that was easy as i am in Switzerland!) that they have black 227mm Competition (double butted 2.0/1.8) spokes on stock. All I have to do now is get hold of the Velocity Aeroheats - which isn't as easy as I thought as the Velocity webshop won't ship out of North America


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## GrayJay (May 16, 2011)

Velocity list the current (US made) 507mm aeroheats as 455g, (Tig weighted some older aeroheats at 420gr.) If low weight is the primary goal, the new 455gr rims are fairly heavy, a generic singlewall rim can be as low as 400gr each. I would theorize that a kid could likely do fine with a 300gr rim but I know of no such lightweigt 507mm rims available. 
Even 28 spokes is likely many more that are needed for a kid on such heavy rims. 28 spokes somewhat constrains you from using a minimal spoke pattern such as can be done with 32 or 36 spoke hubs/rims. Radial 14 spoke pattern can be used with rim brakes but will not work with disks as you cannot lace 7 crossed spokes per side (since 7 is an odd number). About the only alternaive lacing I can invision would be to lace the drive side with 14 crossed spokes counterbalanced by 7 radial spokes on non-drive side so producing a 21 spoke wheel. You could even do same 21 spoke lacing for a front disk wheel Weight savings of about 40gr per wheel by dropping 7 spokes.


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## TigWorld (Feb 8, 2010)

When I recently went through the process of looking for lightweight 24" rims, I did come across the deviant rims. They are disc specific, wide and claimed to weigh 415g. Also cheaper than Aeroheats. Supposed to come in 28h, 32h and 36h so you could use a 36h hub and get creative with reduced spoke lacings (ie 18 spoke wheels).


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## dizpark (Jun 4, 2012)

GrayJay said:


> Using the only available (heavy) rim extrusons designed for adult strength wheels, for a kid bike you can safely drop the # of spokes and still have a strong (and lighter) wheel. Symetrical patterns of 12,18,24,36 spokes are possible from using 36 hole rims/hubs


You are our resident wheel building expert here :thumbsup: I am also planning a 24 inch mtb build for my kids. Good quality 24 inch 507 rims are indeed a rarity, but I have found French Mach1 made 36 hole double wall V-brake rims locally. These are Mach1 507x19 rims, I cannot find any info about these on the internet. Anyway, they appear to be good quality, claimed weight is 440, but I measured hem to be 420 g. I plan to lace them to novatec sealed cartridge hubs - these come in 36 and 32 h.

My question is - what would be your advice about the lacing pattern if I want to go for 18 or 24 spokes (12 spokes radial build appears to be too radical to me ) on 36 h hub. These will be v-brake only, and the rims have holes arranged in alternating left-right pattern.

I googled around a bit but got no wiser. On 18 spokes solution I found this
63xc.com--How To | 18 spokes
arranging 18 spokes in crows foot pattern. this looks like an elegant solution and easy to calculate spoke lengths.


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## GrayJay (May 16, 2011)

On a front wheel, if not using disk (or hub) brakes it is simpler (and slighlty lighter) to just use radial lacing instead of crow foot as only 1 spoke length is needed. See Tigs recent writeup of the 18 spoke radial he built. Only slight annoyance with an 18 spoke wheel is that if it is laced symetrically, then the spokes for one side are placed in rim holes that angle opposite direction so the spokes for one side get bent just beyond the nipple. Also, since the hubs spoke holes on each flange are offset from the opposite flange by 10 degrees, the spokes are not truely radial but instead one side is angled 5 degree forward, other side is 5 degree backward from radial. I am sure it will still work fine on a kids bike but as an obsessive wheelbuilder, such tiny details bother me. 
Alternative is to lace an 18 spoke radial wheel with a pattern of using two consecutive rim spoke holes then skip two rim holes. THis pattern gets the spokes in rim holes that point correctly to each side and there is no offset from radial. 
Using 12 spokes, the wheel is entirely symetrical and technically correct. Spokes go into rim holes that are angled correctly, no offset from radial, and the spacing of spokes around the rim is even. 

For a rear wheel, I considered the 9+9=18 spoke crowsfoot pattern but I was a bit uncomfortable with having only 3 trailing spokes on the drive side transmitting all of the drive torque, seems that most of the spokes I ever break on my own wheels have been the trailing drive sides. The 12+6=18 pattern I used on rear has twice as many trailing drive side spokes (6) as crowsfoot. Having only 6 radial non-drive side spokes requires twice the normal tension for these spokes so thier tension is much better ballanced than a typical dished wheel using only 1/2 the tension on the non-drive side. Technically incorrect downside of the 12/6 pattern is that the 6 radial spokes go into rim holes oriented wrong side direction.


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