Wheel building and spokes

A 32- or 36-spoke wheel built with a SPEEDHUB is stiffer than a conventional rear wheel — roughly as strong as a 48-spoke tandem wheel. The hub’s flanges are symmetrical, the rim sits centred, and every spoke runs at the same angle with the same tension. For it to last decades, even in hard conditions, a few rules apply.

The rules

• Crossing: two crosses for 26-inch rims and larger (650B, 28, 29), one cross for 24-inch and smaller. Never three, and never radial — the spokes have to carry drive torque too.
• Rim: 32 or 36 holes only, ideally a box-section aluminium rim with eyelets of at least 4.4 mm or holes drilled in the spoke direction. With small eyelets the nipple cannot align with the spoke, and the spoke kinks at the nipple.
• Spoke: the SPEEDHUB needs a 2.9 mm elbow length. In the aftermarket that is the 2.0/1.8/2.0 mm DD spoke; reinforced-elbow spokes (2.2 or 2.3 mm) need a 3.7 mm elbow length.
• Tension: at least 1,000 N with the tyre inflated (to working pressure), at least 1,300 N without it.
• Flange ring: always fit one before lacing — see below.
• Disc brake (DB) hubs need no different pattern on the disc side, because the shell is torsionally stiff.
• On rims of 24 inches and smaller, the spokes must not cross the shell cover screws.

Tip

Shift to gear 11 while lacing — the wheel turns more easily. With internal actuation, shift by pulling the bayonet tips; with external, with an 8 mm spanner on the shift housing.

Checking the spoke fit

The wrong elbow is the flange’s worst enemy:

• elbow too long, or wire too thin at the elbow: the spoke can move axially after truing and the elbow opens up — spoke breakage;
• elbow too short, or wire too thick at the elbow: lacing and tensioning dent the flange hole — flange cracks.

To check: lace a spoke from the outside on the cover-side flange so its head sits in the countersink with no noticeable resistance. Hold the hub horizontal, sprocket side up, spoke pointing radially outwards — its threaded end should then sit within the factory range. Repeat with a spoke laced from the inside on the sprocket-side flange. The causes of flange damage are described in Fault diagnosis.

Flange rings

The flange ring supports the spoke flange from outside: should the flange ever crack, it stops the spoke tearing out. Especially recommended for tandems, touring bikes, e-bikes, cargo bikes and riders over 100 kg — and mandatory from the second lacing on. It is black anodised aluminium (20 g).

Which kit you need is shown by the “Made in Germany” lettering on the shell:

Lettering	Kit	Contents
underlined	Art. no. 8524	1 small + 1 large ring (groove towards the cover) — only the cover-side flange is raised
not underlined	Art. no. 8523	2 small rings — both flanges are the same

The 8523 kit is for hubs below these serial numbers:

Colour and holes	Below serial no.
silver, 32 holes	196922
silver, 36 holes	198454
black, 32 holes	196713
black, 36 holes	196521
red, 32 holes	197520
red, 36 holes	197980

Caution

Red powder-coated shells are compatible with the flange ring only after a prior check.

Spoke length

The SPEEDHUB’s flange circle is 100 mm, its spoke holes 2.7 mm (2.5 mm up to serial number 44321). With symmetrical flanges, every spoke is the same length. The tables below apply to 135, 142 and 148 mm hubs, by effective rim diameter (ERD).

32 spokes

Wheel size	Crosses	ERD (mm)	Spoke length (mm)
18”	1	341–343	128
		344	130
20”	1	372–373	142
		374–377	144
		378–381	146
		382–385	148
		386–389	150
		390–394	152
24”	1	472–476	192
		477–480	194
		481–484	196
		485–489	198
		490–493	200
		494–497	202
		498–501	204
		502–503	206
26”	2	516–519	226
		520–523	228
		524–527	230
		528–531	232
		532–535	234
		536–539	236
		540–543	238
		544–547	240
		548–551	242
		552–555	244
650B	2	556–559	246
		560–563	248
		564–567	250
		568–571	252
		572–575	254
		576–579	256
		580–583	258
28”	2	584–587	260
		588–592	262
		593–596	264
		597–600	266
		601–604	268
		605–608	270
29”	2	609–612	272
		613–616	274
		617–620	276
		621–624	278
		625–628	280
		629–632	282

36 spokes

Wheel size	Crosses	ERD (mm)	Spoke length (mm)
18”	1	341–342	126
		343–344	128
20”	1	372–375	142
		376–379	144
		380–383	146
		384–387	148
		388–392	150
		393–396	152
24”	1	472–474	190
		475–478	192
		479–482	194
		483–486	196
		487–490	198
		491–494	200
		495–498	202
		499–502	204
		503	206
26”	2	516–517	222
		518–522	224
		523–526	226
		527–530	228
		531–534	230
		535–538	232
		539–542	234
		543–546	236
		547–550	238
		551–554	240
		555–558	242
		559–562	244
650B	2	563–566	246
		567–570	248
		571–574	250
		575–578	252
		579–582	254
28”	2	583–586	256
		587–590	258
		591–594	260
		595–598	262
		599–602	264
		603–607	266
29”	2	608–611	268
		612–615	270
		616–619	272
		620–623	274
		624–627	276
		628–631	278

XL and XXL hubs (170–197 mm), 32 spokes

Fatbike rims have their spoke holes offset from the rim’s centre, so the length depends on the offset too. From 585 mm ERD — so not with a 29” rim either — there is no suitable spoke length for an XL/XXL hub.

Wheel size	Crosses	ERD (mm)	12.5 mm offset (mm)	20 mm offset (mm)
26”	2	516–519	228	226
		520–523	230	228
		524–527	232	230
		528–531	234	232
		532–535	236	234
		536–539	238	236
		540–544	240	238
		545–548	242	240
		549–552	244	242
		553–556	246	244
650B	2	557–560	248	246
		561–564	248–250	248
		565–568	250–252	250
		569–572	252–254	252
		573–576	254–256	254
		577–580	256–258	256
		581–584	258–260	258

If your rim is not in the table, calculate it:

L = √(0.25·d² + 3400 − 50·d·c)

where d is the rim diameter at the nipple seat (mm), and c is 0.924 (32 holes) or 0.940 (36 holes) for one cross, 0.707 (32 holes) or 0.770 (36 holes) for two. Example: d = 539 mm, 32 holes, two crosses → L = 238.69 mm, so 238 mm (always rounded to an even length).

To measure d: measure the nipple head height (K) and the length of two spokes from the start of the thread to the inside of the bend (S). Put them through two opposite rim holes, screw the nipples on until flush with the spoke end, pull the two spokes together in the middle of the rim and measure the distance X between them: d = 2·S + X − 2·K.

Leave it to us

We build SPEEDHUB wheels in our workshop too, with the right spokes and flange ring — our prices are on the home page.