CyberRear SP 2B+ From 116g
Light, clean and clever CyberRear SP 2B+ features the widest possible spoke camber to offer higher lateral stiffness Like CyberRear SPD 3+ spoke holes holes are now 3D angled to allow a perfect alignment of spokes
- Description
- Hub Dimensions
- Wheel building
- Spoke-End-Diameter
- Tech Tips
- Bearing Options
- Manuals
- Spare Parts
Tech info
Description
Brompton specific rear hub, compatible with A-C-P and T-Line, 20 or 24h straight pull spokes.
Optimized spoke camber, Ø 2.8mm spoke holes 3D angled and rounded for perfect spoke-to-rim alignment.
Compatible cogs: up to 6 speed cogs (individual cogs) up to 7 speed cogs (one-piece construction).
Oversized axle Ø17mm (112mm width), ABEC5 cartridge bearings (high load capacity) with external preload tuner.
Hub is supplied with special Titanium bolts for an extremely lightweiht wheel securing (B-Lock system).
Oversized and sealed freewheel mech, OR-spring, Titanium 32T ratchet wheel.
Black anodized hub-body with laser etched graphics.
Weight: 116g for 20h HyC Bearings (B-Lock special securing system 7.8g - Tensioner bolt 3.8g)
Hub Dimensions
Wheel building
CyberFront SP-B / CyberRear SP 2B+ wheel-building
Here you find all the necessary instructions to realize your dream wheels with pre-calculated spoke lengths
Follow instructions step by step:
1)Measure your "spoke-end diameter" (not ERD)
2)Find front hub spoke length on table A
3)Find your rear spoke length (left side) on table B
4)Find your rear spoke length and lacing pattern (drive side) on table C
(All measures are expressed in mm)
4)Lace the wheel respecting correct lacing pattern (see below)
Maximum spoke tension:- Refer to spcific manuals
Warning: spoke lacing and tensioning require skills and experience,refer to an expert professional wheel builder for these operations
1) "Spoke-End-Diameter"
Rim manufacturers always offer ERD figures however we warmly recommend to precisely measure the rim+nipple combination
Basically a correct spoke calculation requires exact "spoke-end diameter" and rim drilling
Spoke-end diameter depends on your rim internal diameter and nipple type
How to measure "Spoke-End-Diameter"
2) CyberFront SP-B
Radial lacing - Straight pull spokes (any drilling count)
|
Spoke-end Diameter
|
Spoke Length
|
|
310
|
143
|
|
315
|
146
|
|
320
|
148
|
|
325
|
151
|
|
330
|
153
|
|
335
|
156
|
|
340
|
158
|
|
345 |
161
|
|
350
|
163
|
Table A
Note: We list "spoke-end diameters" every 5mm step. If your "spoke-end diameter" measure is in between 2 steps adjust your spoke length consequently
3) CyberRear SP 2B+
Left side- Straight pull spokes
|
Spoke-end Diameter
|
Spoke Length
24H Crossed Lacing |
Spoke Length
20H Crossed Lacing |
Spoke Length
28H Radial Lacing |
|
310
|
154
|
159
|
143
|
|
315
|
157
|
161
|
146
|
|
320
|
159
|
164
|
148
|
|
325
|
162
|
166
|
150
|
|
330
|
164
|
168
|
153
|
|
335
|
167
|
171
|
156
|
|
340
|
169
|
173
|
158
|
|
345 |
172
|
176
|
160
|
|
350
|
174
|
178
|
163
|
Table B
4)CyberRear SP 2B+
Drive side - Straight pull spokes
|
Spoke-end Diameter
|
Spoke Length
24H |
Spoke Length
20H and 28H |
|
310
|
152
|
159
|
|
315
|
154
|
161
|
|
320
|
157
|
164
|
|
325
|
159
|
166
|
|
330
|
161
|
168
|
|
335
|
164
|
171
|
|
340
|
166
|
173
|
|
345 |
169
|
176
|
|
350
|
171
|
178
|
Table C
Lacing: correct lacing patterns with straiht-pull spokes must be as shown below

Spoke-End-Diameter
How to measure "Spoke-End-Diameter"
Spoke-end diameter depends on your rim and nipple type and length.
Below you see how to measure SED for both nipple types:
External nipple configuration
Internal nipple configuration
Take measures very precisely because a well correct nipple/spoke assembly accepts a spoke-length tolerance of +/-1mm only.
(All measures are expressed in mm)
External nipple configuration
1) Insert two J-spokes (random size) with the nipples (of your final build) into 2 opposite rim holes.

This simple trick helps to keep spokes aligned and slightly tensioned.

2) Precisely measure distance between nipples.

Be careful to take measure between the 2 nipple-ends.

3) Add 2x by the nipple height (of your final build) to the measure above.
This gives "Spoke-End-Diameter".
Note: with slotted nipples measure height inside the cut.


Internal nipple configuration
You can get the necessary data following the procedure below:
1) Precisely measure outer rim diameter (A).

2) Insert a nipple of your final build into a hole (use a spoke to hold nipple in position).
3) Precisely measure distance between nipple-top and outer rim diameter (B).

This is the correct caliper positioning inside the rim (don't cut your rim!)

4) A-2B = "Spoke-End-Diameter".
Tech Tips
CyberRear / Type of Use and Rider Weight
The whole hub lineup named "Cyber" is specifically designed for Road use.
We do not limit rider weight since the structure of all our hubs is very well dimensioned.
However make sure your riding environment is "Road" type and that that shortest gear ratio is in the "Road" range, that means not shorter than 1:1.
In case you need shorter gear ratio or to ride offroad we recommend to use the "Hyper" hub lineup that's specifically designed for MTB and offroad use where the gear ratio can be twice more short.
Additionally the whole "Hyper" lineup comes standard equipped with ABI 440c stainless bearings and additional external seals in order to withstand to the adverse environment of offroad riding.
Hub-Servicing / general
We warmly recommend to read well the instruction manuals and execute a cleaning-servicing by yourself.
As general rule we can't recommend bicycle mechanics for the servicing of Extralite hubs unless they are truly ready to follow our manuals very strictly.
That because our hubs work on rather different principles than the common brand/models on the market.
In case of bearing replacement you find good guidelines on our Tech Tips / Bearing area.
If you need you'll need a really full servicing you can send your hub/wheel to us for a proper service.
(as ready ask for shipping instructions and authorization code)
Regularly service your Hyper hub strictly following its instruction manual step by step (don't skip any step).
Again: never wrench or service Extralite hubs by instinct or only by past experience!
Micro-Tuner
All our hubs feature a device "micro-tuner" that offers a very precise setting of bearing preload.
Remind to execute the "micro-tuner" tuning after your wheel has been laced, see how on hub manual at the Bearing-Preload chapter.
Basic diagnosis
When the micro-tuner is correctly set you should not feel lateral movements at all.
- Axial play (lateral movement left-right of axle) will also produce play at the rim.
- Radial play (when you have up-down movement at the hub) means the outer part is wider than the inner part: worn our bearing or axle etc.
In all cases the freehub should not have any noticeable radial play.
If you have a noticeable radial play at the freehub check it well, probably a bearing is gone or so blocked that has worn-out the axle.
Hub-noises / general
In over a decade we never found a single hub capable of making noise by itself (unless with a completely blown bearing or freehub).
Once the hub has been properly serviced and micro-tuner position adjusted (see "bearing-preload" procedure on manual) I would recommend to investigate well on the hub peripherals.
That's to say:
- Spokes (that should not touch each other)
- Frame dropout (where even a small 0.2mm play of the axle can produce an annoying noise)
- Cog assembly (that doesn't need grease nor more than 25Nm torquing to stay properly in position).
- Remind that the cause of the noise is generally never where you suppose.
Keep the above well in mind and you'll be able to sort it out with some dedication.
Opening "Rear Axle-Ends" on Thru-axle models
Use only two 17mm closed wrenches.

Feel free to ask for additional tech info, we'll be happy to help!
Bearing Options
All Extralite hubs and wheels are offered with a choice of ready installed bearings among the best available today.
All bearings feature low-friction rubber seals on both sides.
Hyper hubs, that are specifically designed for off-road use, feature an additional external O-r seal that protects the bearing seals.
Internal bearing selection
Each bearing unit is individually selected by Extralite staff, we check seal drag, rolling smoothness then select and divide them 3 different fitting classes of internal diameter, each class is 2 microns by the next one.
Despite all our bearings come directly from very high quality manufacturers our staff individually checks each unit for rolling smoothness and bore dimensional tolerance.
Extralite staff checks rolling smoothness and seal drag resistance first, then all the units passed are selected and divided in 3 different fitting classes of internal bore, each class is 2 microns by the next one. All that allows our famous truly perfect axle to bearing fitting that together with our precise bearing preload offers very high mileage with minimal rolling resitance.
| Abec5 Steel bearings | Famous Abi-Enduro ABEC 5 precision bearings Standard equipment for all Extralite Road hubs |
|
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Plus | Minus |
|
High mileage Good rolling resistance High impact resistance Average best choice for dry environments |
Sensible to water & moisture inside the hub | |
| ABI 440C Stainless bearings | Abi-Enduro precision 440C Stainless bearings Standard equipment for all Extralite MTB hubs 4-5g average weight-saving on the hubset (compared to Abec5) |
|
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Plus | Minus |
|
High corrosion resistance Highly resistant to water/moisture (inside hub too) Medium-high impact resistance Average best choice for humid environment |
Medium mileage Medium rolling resistance |
|
| HYC HyperCeramic | Extralite Hi-tech Ceramic bearings, hyper-low friction factor Extremely durable and smooth, never-rustable 5-6g average weight-saving on the hubset (compared to Abec5) |
|
|
Stainless Races: AMS5618 Cryogenically treated Really trick! |
Plus | Minus |
|
Low rolling resistance Low weight High mileage High impact resistance Highly resistant to water/moisture (inside hub too) Best choice for max racing performance and durability |
Installation requires very good skills | |
|
XD-15 Ceramic
|
Enduro trickiest Ceramic bearings |
|
| Plus | Minus | |
|
Low rolling resistance Highest mileage Fully openable and rebuildable Highly resistant to water, moisture and salt Best choice for max racing performance and durability |
Expensive Installation requires very good skills |
|
Read well these basic info before ordering the parts.
Bearing replacement is not an easy operation as it may seem.
Additionally the installation of any kind of Ceramic bearings requires a very good specific expertise.
Extralite offers complete tool-sets for hub maintenance: the Pro-tool kit 1 and Bearing-sitter includes bearing inserting tools in every bearing sizes used on UltraHubs / HyperHubs / CyberHubs.
If your hub was originally equipped with standard bearings it will probably require micro-tolerance adjustments to axle and bearing fittings, this
to allow proper bearing rotation and durability (these operations are for real experts only). Alternatively send your hub to us for this servicing.
Read well Bearing Installation Tips before attempting a bearing replacement.
This option has been offered till 2024
|
HDC Heavy-Duty Ceramic
|
Hi-quality Heavy-Duty Hybrid Ceramic bearing |
|
![]() |
Plus |
Minus |
|
Good mileage Low rolling resistance Medium-high impact resistance Medium resistance in humid environment Good choice for best racing performance |
Complex installation Sensible to water & moisture inside the hub |
|
Manuals
Spare Parts
Spare Parts
41,74 €
10,43 €
10,43 €
2,61 €
16,52 €
10,43 €
10,43 €
7,83 €
86,09 €
1,74 €
103,48 €
190,43 €
16,52 €
10,43 €





