Bikes and Wheels

Tech Talk
Wind Tunnel Testing
of Aerodynamic
Bikes and Wheels
Text & Photos: Editorial Dept.
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Tech Talk
I
n March of this year, Cycling
Update – Wheel Giant’s consumer magazine – and the CHC
cooperatively conducted Taiwan’s first wind tunnel testing of
aerodynamic bicycle products.
The tested products consisted of
19 aerodynamic road bikes, time
trial bikes, and aerodynamic
wheels. While any assessment
of the overall performance of
both bicycles and wheels must
also take into consideration ge-
ometry, stiffness, strength, and
weight, this report only focuses
on aerodynamic performance,
and the test data only indicates
wind resistance for each product.
Testing Methodology
The bicycles and wheels
to be tested were mounted on
CHC’s custom-built jig. Verified
computational fluid dynamics
(CFD) software was used to enwww.biketaiwan.com
sure that testing results expressed
actual wind resistance during
riding. Apart from the mounting
of special devices to measure the
wind resistance coefficient, a rotating platform was also used to
measure wind resistance at different angles to the wind. The test
wind speed was set at 30 mph (48
kph), and measurements indicated only the resistance to motion
in a forward direction. Resistance coefficients were rounded
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Tech Talk
to whole numbers in grams; the
greater the value, the greater the
wind resistance.
Complete Bicycles
The tested products in this
category consisted of aerodynamic road bikes and time trial bikes.
However, as bicycles are asymmetrical, measurements were
performed with wind from both
the right and left sides. From the
perspective of someone sitting on
the bike, the measurement scope
extended from the center point
to 15° on both right and left. One
measurement was performed for
each 5° turn of the rotating platform. Seven measurements were
taken for each product: left 15°,
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left 10°, left 5°, straight ahead 0°,
right 5°, right 10°, and right 15°.
The testing team paid
close attention to any details that
might affect test results. In order
to insure consistency in testing,
chains were placed on the largest
front sprocket and smallest rear
sprocket (the highest gear ratio),
and the left and right cranks were
placed in a horizontal position
with the right crank extending
forward, and no pedals were installed. Any parts that could not
be adjusted were left with the
factory settings during testing.
For example, saddle height could
not be adjusted on ISP frames,
nor could the handlebar grip
height be made consistent, and
the different frame sizes also afwww.biketaiwan.com
fected the data.
Wheels
As the front wheel of a bicycle receives the greatest wind
exposure, only front wheels were
tested in this project. Tire pressure was set at 100psi, and a roller was used to simulate rotation
of the wheels in an unloaded condition. Because front wheels are
symmetrical, the measurement
scope extended from the center
point to 20° on the left. One measurement was performed for each
5° turn of the rotating platform. A
total of five measurements were
taken in the sequence of straight
ahead 0°, right 5°, right 10°, right
15°, and right 20°.
Aerodynamic Road Bikes
Tech Talk
Felt AR5
The Felt AR5 frame is made of UHC Advanced carbon
fiber, and the frame geometry and tube shapes are customdesigned to easily cut through the wind. This frame allows
cyclists to enjoy a rock-bottom wind resistance coefficient
at an entry-level price. This frame was equipped with a Shimano 105 shift system and FSA Gossamer Pro BB386 EVO
chainrings. A complete bicycle with this frame exhibited
excellent handling, a high level of comfort, and the ability to
easily tackle all road conditions.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
UHC Advanced MMC carbon fiber
Shimano 105 STI
Shimano 105 STI
Felt VS Aero 2014 double
butted aluminum
FSA Gossamer Pro BB386
EVO 52/36T
Shimano 11-25T
Felt AeroR3
Vittoria Rubino Pro Slick,
700cX23c,150tpi
Prologo Zero T2.0
51, 54, 56, 58（cm）
---
Wind tunnel laboratory test data
Left rotation 15˚
1309
Left rotation 10˚
1286
Left rotation 5˚
1201
Front
1102
Right rotation 5˚
1185
Right rotation 10˚
1260
Right rotation 15˚
1294
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Tech Talk
Aerodynamic Road Bikes
Merida Reacto 909-20
The Reacto frame possesses fluid lines and amazingly
low wind resistance. It nevertheless also offers ultra-high
rigidity, and its distinctive DCT double-chamber carbon fiber frame tubes ensure that no pedaling energy is lost. The
frame’s patented integral S-Flex flexible seat tube employs a
special window-frame structure, and derives flexibility from
the use of rubber and carbon compounds. In addition, an allnew 1.5” X tapered frame head tube is paired with integral
Bio Flex front forks, providing precise handling and making
this frame a force to be reckoned with on high-speed downhills.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
Revo Nano
Shimano Dura-Ace
Shimano Dura-Ace
FSA K-Force Carbon OS
Shimano Dura-Ace
Shimano CS-7900 11-25
SRAM S40
Vittoria Diamante Pro 23 220
Fold
Selle Italia SLR XC
47, 50, 52, 54, 56, 59（cm）
7.17kg
Wind tunnel laboratory test data
Left rotation 15˚
1170
Left rotation 10˚
1161
Left rotation 5˚
1102
Front
998
Right rotation 5˚
1039
Right rotation 10˚
1163
Right rotation 15˚
1171
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Aerodynamic Road Bikes
Ridley Noah Fast IBS
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
50, 40, 30T
high modulus carbon fiber
Campagnolo Record 11S
Campagnolo Record 11S
Deda RHM01
Rotor 3DF
Campagnolo Record 11S
Cole T45 Tubular
Verdestein Fortezza
Pro Tricomp
4ZA Cirrus Pro Team Edition
XS, S, M
7.3kg
Tech Talk
The Noah Fast is Ridley’s most aerodynamic frame,
and hits the sweet spot between aerodynamics and frame
performance. F-Brake technology seamlessly integrates the
front and rear brakes. This approach reduces overall weight
and gives the frame an even more fluid appearance, and also
reduces wind turbulence from the brake calipers. In addition,
with Ridley’s innovative F-Splitfork design, guide openings
on the front forks and seat stays absorb turbulence and stabilize the rotational inertia of the wheels. Special F-Surface
wind resistance strips increase the smoothness of airflow near
the frame, boosting the average speed of the bike.
Wind tunnel laboratory test data
Left rotation 15˚
1274
Left rotation 10˚
1270
Left rotation 5˚
1172
Front
1073
Right rotation 5˚
1150
Right rotation 10˚
1249
Right rotation 15˚
1280
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Tech Talk
Aerodynamic Road Bikes
Scott Foil 20
A next-generation super racing bike, the Scott Foil 20
is a perfect combination of light weight, rigidity, and aerodynamic design. All R&D, design, and manufacturing processes
for the Foil were performed in the Mercedes Benz F1 wind
tunnel laboratory, yielding a custom-designed bike featuring
cutting-edge aerodynamic technology. The Foil 20 employs
high-stiffness HMF-NET carbon fibers together with Scott’s
patented integrated molding process, and a coordinated inner
and outer strengthening concept enables the frame to achieve
the perfect harmony and balance.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
HMF-NET carbon fibers &
patented integrated molding
process
Shimano Ultegra 6700 (CT 20
speed)
Shimano Ultegra 6700
Scott Road Pilot Pro OS
Shimano Ultegra 6700
Shimano Ultegra 6700
Mavic Cosmic Elite
Continental Ultra Race fold
Scott Road Pro SL
XXS, XS, S, M, L, XL, XXL
7.40 kg
Wind tunnel laboratory test data
Left rotation 15˚
1118
Left rotation 10˚
1073
Left rotation 5˚
1051
Front
1002
Right rotation 5˚
1030
Right rotation 10˚
1066
Right rotation 15˚
1096
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Time Trial Bikes
Tech Talk
Argon 18 E-118
The Argon E-118 features a 7105HM carbon fiber frame,
ONEness 2.0 integral front forks, and time trial handlebars. It
achieves optimal low wind resistance through the use of hidden
brake calipers and aerodynamic calculations adapted from F1
racing car design. The bike’s unique AFS-Tri triathlon frame
geometry features a low bottom bracket height, which lowers
the bike’s center of gravity and increases high-speed cornering
stability. The carbon fiber ASP-7500 dual-angle seatpost and
AHB-7500 handlebars ensure that riders can assume an ideal
racing posture. The bottom bracket specifications are BB86,
and the frame is compatible with a Di2 shift system.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
carbon fiber
SRAM Force
TRP disc brakes
E118 ONEness 2.0
Vision TriMAX Carbon
SRAM PG1070
Vision Metron 81
Vittoria Corsa EVO CX
Aspide TT
XS, S, M, L
frame 1,225g（M）
front fork 545g
Wind tunnel laboratory test data
Left rotation 15˚
876
Left rotation 10˚
911
Left rotation 5˚
981
Front
938
Right rotation 5˚
971
Right rotation 10˚
929
Right rotation 15˚
908
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Tech Talk
Time Trial Bikes
Aster ATT
The Aster ATT employs high-modulus carbon fiber
composite, and its design features a hidden conical headset
and hidden cables. And on top of its high-performance design, the ATT also boasts attractively streamlined styling: the
knife-blade tubing profile reduces the frame’s frontal area,
and performance has been verified via aerodynamic testing.
The ATT pairs low wind resistance with a lightweight structural design, while making sure that cyclists enjoy high rigidity and optimum torque while riding.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
high-modulus
SRAM New Red
SRAM New Red
Aster carbon fiber
SRAM New Red 50/34
SRAM New Red 11-28T
Aster T85
Tufo CS33 Pro
Aster AP1
47, 49, 52（cm）
7.38kg
Wind tunnel laboratory test data
Left rotation 15˚
1023
Left rotation 10˚
1026
Left rotation 5˚
1000
Front
960
Right rotation 5˚
1008
Right rotation 10˚
1024
Right rotation 15˚
1044
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Time Trial Bikes
Tech Talk
Kuota Kalibur
The Kalibur is Kuota’s flagship time trial bike. This
year’s version incorporates some all-new technology, including routing of air flow from the seat post through the rear
wheel, diversion around the seat clamp to reduce eddy flow
in the rear, and use of a low-drag head tube and KIC hidden
cables. These measures ensure that the frame has sharply reduced air resistance. The HPT high-strength bottom bracket
has PF30 specifications, and is compatible with either a Di2
electronic shift system or mechanical shift system.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
Kuota Kalibur
SRAM Red
SRAM Red
Vision TriMax Carbon Si
Vision TriMAX Carbon
SRAM OG1090
Vision Metron 90 /
Metron Disc
Vittoria Corsa EVO CX
Aspide TT
XS, S, M, L
frame 1,320g（S）
front fork 350g
Wind tunnel laboratory test data
Left rotation 15˚
803
Left rotation 10˚
843
Left rotation 5˚
879
Front
905
Right rotation 5˚
913
Right rotation 10˚
883
Right rotation 15˚
841
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Tech Talk
Time Trial Bikes
Ridley Bikes Dean ISP
Ridley was pioneer in applying aerodynamic concepts to
time trial frames, and has applied its proprietary F-Surface and FSplitfork aerodynamic technologies to the Dean ISP frame. The
F-Splitfork technology relies on a split front fork and seat stay
design to reduce air holdup caused by the spokes of the turning
wheels. Specialized F-Surface wind resistance strips increase the
smoothness of airflow near the frame, which boosts the average
speed of the bike. The frame also employs a tapered head tube
that is 1-1/8” at the top and 1-1/2” at the bottom, which resolves
the problem of instability caused by a short head tube in time
trial bikes. There are 76°/78° saddle angle options, and riders can
chose the angle that suits them best when riding or racing.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
50, 40, 30T
High modulus carbon fiber
Shimano Ultegra 6700
Deda TT Brakes
3T Aura Pro
Rotor 3DF
Shimano Ultegra 6700
Cole T85
Verdestein Fortezza
Pro Tricomp
Selle San Marco Ponza TT
XS, S, M
8.2kg
Wind tunnel laboratory test data
Left rotation 15˚
1080
Left rotation 10˚
1108
Left rotation 5˚
1065
Front
1006
Right rotation 5˚
1024
Right rotation 10˚
1076
Right rotation 15˚
1064
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Time Trial Bikes
Tech Talk
Swift Neurogen
The Swift Neurogen is manufactured using high-coefficient T1000 and M40 carbon fiber material, accompanied by
a special carbon fiber stacking method, and has minimal paint
and printing in order to eliminate as much weight as possible.
The frame is stable, rigid, and responsive, while complying
with UCI regulations. The down tube, seat tube, and seat stay
geometry have been designed based on NACA airfoil sections,
and the use of an even larger angle reduces drag. The ultra-long
160 mm head tube and hidden brake system also yield significant aerodynamic benefits, and the shape of the seat tube is
harmonized with the rear wheel to effectively control air flow.
Frame
Shifting system
Braking system
Handlebars
Chainwheels
Freewheels
Wheels
Tires
Saddle
Dimensions
Reference weight
SwiftCarbon Neurogen
SRAM Red
SRAM Red
Vision
SRAM Red
SRAM Red
SwiftCarbon Hemoglobin
Vittoria
SwiftCarbon
XS, S, M, L
7.7kg
Wind tunnel laboratory test data
Left rotation 15˚
826
Left rotation 10˚
824
Left rotation 5˚
891
Front
893
Right rotation 5˚
899
Right rotation 10˚
870
Right rotation 15˚
846
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Tech Talk Wheels
Campagnolo Bora Ultra Two
Campagnolo’s ultra-high-end Bora Ultra Two wheels are
favorites of professional riders and amateur cyclists alike. The
wheels utilize USB (Ultra Smooth Bearings), optimized ceramic
ball bearings that can cut weight by 30% and increase stiffness by
40% compared to other Campagnolo bearings. CULT (Ceramic
Ultimate Level Technology) gives the wheels high corrosion resistance while providing an excellent lubricating effect and feeling of
smoothness.
Applicable shift system
Rim height (front, rear)
Rim width (front, rear)
Spoke number
(front, rear)
Hub type
Spoke type
Nipple
Weight
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Campagnolo、Shimano
50/50（mm）
20/20（mm）
18/21
Carbon fiber
Stainless steel
aluminum alloy
1,310g
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Wind tunnel laboratory test data
Front
355
Right rotation 5˚
378
Right rotation 10˚
381
Right rotation 15˚
372
Right rotation 20˚
382
Wheels
FFWD F4R-C
Applicable shift system Shimano（10s, 11s）
Campagnolo（10, 11s）
Rim height (front, rear) 38/38（mm）
Rim width (front, rear) 20/20（mm）
Spoke number
20/24
(front, rear)
Hub type
DT Swiss-DT 240S´
Spoke type
DT Swiss-DT Aerolite
Nipple
DT Pro Lock Brass
Weight
1,630g
Wind tunnel laboratory test data
Front
Right rotation 5˚
Right rotation 10˚
Right rotation 15˚
Right rotation 20˚
329
358
373
365
377
Tech Talk
FFWD is a new Dutch brand specializing in carbon
fiber wheels for high-end racing bikes. All FFWD wheels
are produced and painted by hand at the well-known Dutch
assembly plant Zoran, and all bear manufacturer’s serial
numbers symbolizing their uniqueness. The F4R-C is designed for climbing and multifunctional use. The wheels are
made using TC35 reinforced high-tensile carbon fiber material providing extraordinary rigidity. The surface fabric layer
is 3K carbon fiber with excellent compressive strength, and
the braking surfaces are considerately designed. The wheels
come with inner flaps and extended valves and wheel bags,
and the manufacturer provides a two-year warranty.
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Tech Talk
Wheels
Fulcrum Racing Speed XLR
Fulcrum’s Racing Speed XLR wheels feature hubs with carbon fiber spindles and aluminum alloy flanges for optimum light
weight. The diameter of the ratchet base has been increased to 78
mm, enhancing acceleration performance. Unique CULT technology employs high-grade ceramic ball bearings that boost rigidity
by 40% and cut weight by 30%, and also provide a pleasing sense
of smoothness and high corrosion resistance. Fulcrum has specially
developed a proprietary composite material for the rims, which resolves the long-term problem of the braking surface on carbon fiber
wheels. These wheels have as good braking performance as aluminum alloy wheels. When wet, it only takes one rotation to clear the
water from the braking surface before the brakes take hold.
Applicable shift system Shimano, SRAM,
Campagnolo
Rim height (front, rear) 50/50（mm）
Rim width (front, rear) 20.5/20.5（mm）
Spoke number
18/21
(front, rear)
Hub type
Carbon fiber/
aluminum alloy
Spoke type
Stainless steel
Nipple
Mo Mag patent
Weight
1,324g
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Wind tunnel laboratory test data
Front
355
Right rotation 5˚
362
Right rotation 10˚
372
Right rotation 15˚
353
Right rotation 20˚
361
Wheels
Tech Talk
Mega ITC
(Inertial Tubeless Carbon)
These 23mm are designed to be used with 23C tubeless tires.
The tires fit the rims perfectly, with minimal gap. The distance between the rims gradually increases from 23mm to 24.6mm, achieving
an excellent wind-shedding effect. The spokes are mounted on the two
sides of the rims, and act as brake discs. The right and left spokes do
not interfere with each other’s air diversion effect, and are nearly impervious to side winds. The spokes are pulled outward from inside in a
pattern centered on the drive points, enabling direct drive of the largest
rim diameter. The structure of each force-bearing point is an inertial
flinging point. This sharply increases inertia and instantaneous acceleration while effectively lowering wind resistance.
Applicable shift system
Rim height (front, rear)
Rim width (front, rear)
Spoke number
(front, rear)
Hub type
Spoke type
Nipple
Weight
9/10/11
58/58（mm）
23/23（mm）
20/24
Mega R20/R24
1422 flat
flat head HEX-12 +
Stainless steel washer
1,630g
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Wind tunnel laboratory test data
Front
329
Right rotation 5˚
307
Right rotation 10˚
287
Right rotation 15˚
314
Right rotation 20˚
320
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Tech Talk
Wheels
Reynolds 72 Aero
Applicable shift system Campagnolo（10/11s）,
Shimano（10/11s）
Rim height (front, rear) 72/72（mm）
Rim width (front, rear) 26.2/26.2（mm）
Spoke number
16/20
(front, rear)
Hub type
Reynolds（front）/
DT Swiss（rear）
Spoke type
DT Swiss
Nipple
Reynolds hidden
Weight
1,608g
Wind tunnel laboratory test data
Front
Right rotation 5˚
Right rotation 10˚
Right rotation 15˚
Right rotation 20˚
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302
299
267
335
342
Reynolds’ 2013 Aero series wheels were designed
with DET aerodynamic technology and CTG braking
technology, and feature DT Swiss straight-pull hubs and
ultra-light carbon fiber rims. The DET concept inherits the
V-shaped rim design of the RZR series, and can effectively
cut drag while significantly improving steering. The extrawide 26.2 mm rims provide outstanding handling and stability, and have superb lateral rigidity. As a result, the wheels
are easy to control in a side wind. CTG braking technology
significantly decreases brake temperature, reducing hightemperature deformation when the company’s proprietary
blue brake blocks are used, to provide smooth and reliable
braking performance.
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Wheels
Rolf-Prima TDF6SL
Tech Talk
The all-new design of Rolf-Prima’s TDF6SL wheels includes
an even wider rim profile and a brand-new shape. This not only
increases tire contact area, but also yields even better aerodynamic
characteristics, minimizing the wind resistance coefficient and ensuring that a side wind poses no problems for the 60 mm-high rims. In
addition to high-strength CNC hub shells made by America’s White
Industries, the wheels also boast titanium alloy ratchet bases. The
small number of high-tension Sapim flat spokes used in the wheels
provides outstanding lateral and forward stiffness. The carbon fiber
weave is denser on the braking surfaces, ensuring durability and
good braking performance. These wheels are only available in a tubular version, and meet UCI and ITU usage standards.
Applicable shift system Shimano（8-11s）,
Campagnolo（11s）
Rim height (front, rear) 60/60（mm）
Rim width (front, rear) 23/23（mm）
Spoke number
16/16
(front, rear)
Hub type
TDF5.5 ceramic bearings,
titanium alloy ratchet
Spoke type
Sapim CX-RAY
Nipple
Sapim
Weight
1,435g
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Wind tunnel laboratory test data
Front
304
Right rotation 5˚
286
Right rotation 10˚
318
Right rotation 15˚
315
Right rotation 20˚
322
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Tech Talk
Wheels
Shimano WH-9000-C50-CL
These carbon fiber inner tube-type wheels employ Shimano’s
patented carbon fiber manufacturing technology. The D2 rim design delivers good aerodynamics and stability, and the OptBal
spoke system ensures rigidity and durability. The recessed copper
spoke heads improve aerodynamics and give the wheels a streamlined appearance, and the extra-wide hub flanges increase lateral
stiffness. The titanium ratchet base provides high strength and
light weight. The simple bearing adjustment ensures smooth power
transmission. Shimano’s track-type ball bearings and ultra-large
7075 alloy axles offer a high level smoothness.
Applicable shift system
Rim height (front, rear)
Rim width (front, rear)
Spoke number
(front, rear)
Hub type
Spoke type
Nipple
Weight
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BMU 2013 Autumn
Dura-Ace 9000
50/50（mm）
23/23（mm）
16/21
high strength light weight
titanium ratchet
2.0-1.8-2.0/Bladed
aluminum alloy
1,672g
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Wind tunnel laboratory test data
Front
315
Right rotation 5˚
305
Right rotation 10˚
353
Right rotation 15˚
336
Right rotation 20˚
338
Wheels
Tech Talk
Trigon CW02
These Trigon rims are 45m m high, and the wheels provide
exceptional rigidity and ultra-low wind resistance. In addition, the
relatively low tire pressure reduces the chance of a blowout, while
providing riders with a high degree of cornering stability and allround riding excitement. The carbon fiber hubs have a precision
positioning design maintaining the tension of each carbon fiber
spoke. The transmission of force to these wheels feels instantaneous, enabling cyclists to maintain an even cadence and high degree of sensitivity on even challenging curving roads and climbs.
Applicable shift system
Rim height (front, rear)
Rim width (front, rear)
Spoke number
(front, rear)
Hub type
Spoke type
Nipple
Weight
Shimano, Campagnolo
45/25（mm）
45/25（mm）
12/18
Carbon fiber
Carbon fiber
No Nipple
1,300g
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Wind tunnel laboratory test data
Front
369
Right rotation 5˚
358
Right rotation 10˚
357
Right rotation 15˚
386
Right rotation 20˚
387
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Tech Talk
Wheels
Vision Metron81
Vision’s all-carbon fiber wheels take tubular tires with a
width of 20-25mm. The wheels feature Metron ceramic bearing
hubs made by Vision, and the optimized wheel structure increases
strength. The bearings have a pre-loaded, adjustable design. Vision’s redesign of the wheels with a wide rim geometry and Ushaped cross-section can ease surface turbulence and achieve the
goal of lower drag. Finally, Vision’s QR-89 carbon fiber quick releases ensure an ever lighter overall weight.
Applicable shift system Shimano（10/11s）
Campagnolo（10/11s）
Rim height (front, rear) 81/81（mm）
Rim width (front, rear) 24.5/24.5（mm）
Spoke number
18/21
(front, rear)
Hub type
Vision Metron
Spoke type
light weight bladed
Nipple
ABS
Weight
1,590g
102
BMU 2013 Autumn
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Wind tunnel laboratory test data
Front
325
Right rotation 5˚
305
Right rotation 10˚
270
Right rotation 15˚
330
Right rotation 20˚
346
Wheels
Tech Talk
ZIPP 404
When Zipp developed and designed its FireCrest Tubular
wheels, it used a laser scanner in order to design an optimal tire bed.
In addition to reducing tire rolling resistance and improving cornering performance, this design ensures that even worn-out tires sit securely in the tire bed. These wheels also feature Zipp’s all-new Carbon
Bridge structure, which employs an “inner frame” reinforcing structure, and relies on a large rim edge curvature to shift external strength
to the rim sidewalls. At the same time, a greater thickness of material
is used in side impact areas to boost overall strength. The rear wheel is
paired with a 188 hub. The bearings on the non-drive side extend outward 7.5mm, and the slightly inward-pointing spoke angle increases
stiffness. These wheels offer the sturdiness needed for classic races,
and the comfort needed for long-distance riding.
Applicable shift system Shimano, SRAM,
Campagnolo
Rim height (front, rear) 58/58（mm）
Rim width (front, rear) 27.5/27.5（mm）
Spoke number
16/20
(front, rear)
Hub type
88/188
Spoke type
Sapim CX-RAY
Nipple
Sapim
Weight
1,355g
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Wind tunnel laboratory test data
Front
315
Right rotation 5˚
305
Right rotation 10˚
277
Right rotation 15˚
294
Right rotation 20˚
311
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