C A S T E L L I - C Y C L I N GGABBA R
WHITE PAPER—The aerodynamic results for the Gabba R are astounding, so we are publishing the complete testing
protocol and results in the interest of full transparency.
We developed the Gabba R for going fast in cold and wet conditions. It was developed to be fasterthan any other jacket, and to limit the aerodynamic drag that comes when you put a jacket over yourrace suit. So we tested both the short- and long-sleeve Gabba R against Castelli’s existing Gabba andPerfetto jackets, as well as testing what happens when you put a Gabba R over the Sanremo BTW roadspeed suit (as used by the Soudal Quick-Step team).
To summarize the results, the new Gabba R is significantly faster than its predecessor Gabba/Perfettomodels, with a 7%-8% lower coefficient of aerodynamic drag (CdA), which translates into approximately
2%-3% faster speeds on the road. Compared to a traditional rain jacket, we see up to 12%-15% lower
CdA — although, admittedly, 50 km/h in a rain jacket is not a very realistic test. Our testing indicates aspeed increase of around 3%-5% in a Gabba R compared to a traditional rain jacket.

G A B B A

The most surprising result is that a short-sleeve Gabba R worn over a Castelli Sanremo BTW speed suit
will actually be faster than just the speed suit in certain conditions. That is an extraordinary statement,
so we’re sharing our data and testing protocol to allow you to see for yourself. We were surprised
ourselves, so we tested it three separate times to confirm. And in all but one test, the Gabba R came out
faster than the speed suit alone. Read on to see where it excels and where it doesn’t.

RW H I T E
P A P E R

1

T E S T D ATA∙∙∙∙Wind Tunnel: Polytechnic University of Milano (Polimi)
Date: January 15, 2024
Rider: Matteo Montaguti (pro 2008-2019)
Bike: Road bikeC A S T E L L I - C Y C L I N GTESTING ROUND 1: WIND TUNNEL

In this test, we specifically tested the new Gabba R short- and long-sleeve jackets against thecurrent Castelli Gabba RoS 2 short-sleeve jacket and the Perfetto RoS 2 long-sleeve jacket, as wellas two separate fully waterproof jackets in the Castelli range, the Slicker Pro and the Gavia jackets.
Additionally, we tested against the Sanremo BTW speed suit, as used by the Soudal Quick-Step team, tocompare the aerodynamics with and without the jacket.
The tests show that the Gabba R is significantly faster than the other jackets in the test, as one wouldexpect. The result that stands out is that the Gabba R, both short- and long-sleeve versions, is fasterthan the Sanremo BTW suit on its own.
A caveat on this test is due to the methodology. It is very difficult to conduct dynamic road bike testingin the wind tunnel with a pedaling rider in an aggressive low position because very few riders are able
to precisely replicate the position repeatedly, so the test results will be dramatically influenced by any
difference in position. For this test, the rider held a more “normal” position with hands on the brakehoods and arms relatively straight. However, this position is more upright than one would expect to seefrom an elite rider at 40 or 50 km/h.

G A B B ARW H I T E
P A P E R

2AERODYNAMIC DRAG (CdA)
C A S T E L L I - C Y C L I N G

40 km/h			50 km/h
Sanremo BTW Suit

0,339 			0,332

Gabba R

0,323 			0,319

Gabba RoS 20,347 			0,347

Gabba R Jacket

0,329 			0,322

Perfetto RoS 2 Jacket

0,359 			0,368

Slicker Pro Jacket

0,375 			0,374

Gavia Gore-Tex Jacket

0,387 			0,382

0,390

0,380

0,370

0,360

0,350

0,340

0,3300,320

40 Km/h

50 Km/hG A B B A

0,310

RSlicker Pro Jacket

Gabba RoS 2Gabba R Jacket
Gavia GoreTex Jacket

P A P E R

Perfetto RoS 2 Jacket

Gabba RW H I T ESanremo BTW Suit3

T E S T D ATA∙∙∙∙

Test section: 1,000 m of back road near Nove, Italy; 1 m total elevation difference
Date: January 28, 2024
Rider: Castelli employees Alvin Nordell and Steve Smith
Bike: Road bikes

C A S T E L L I - C Y C L I N GTESTING ROUND 2: ROAD TEST

∙ Conditions: Sunny, calm winds, 13°C
∙ Computer: Garmin 1030 for Alvin, Wahoo Elemnt Roam for Steve
After seeing the surprising wind-tunnel results of the Gabba R being faster than the Sanremo suitwithout a jacket, we conducted a follow-up test of the short- and long-sleeve jackets with Castelli
employees on a road course.
We used a 1 km stretch of a quiet, mostly flat road and ran multiple successive runs with and without
the jacket. We recorded the time and average speed as well as nominal and average watts for each run.
We did three round-trip runs with each outfit, which resulted in six timings for each product. Each rider
tried to maintain a certain power output with the intention to see time and speed differences based on
the clothing. Both riders maintained a low aero position with hands on the hoods, as evidenced by thespeed-to-power ratio.
This sort of testing, of course, cannot control for position, wind speed (calm at the start, very slightwind at the end, as we see in the results — however, the out-and-back testing negates the effect ofthe wind), entry speed, etc. To reduce the variables, we did multiple repeats, swapping A-B-A-B tests
back-to-back, and then normalized the speed based on the power output. Note that time normalization isa simple mathematical formula involving the difference in recorded power compared to average power
for the overall test.

RW H I T E
P A P E R

In this test, we confirm the results of the first wind tunnel tests for the short-sleeve Gabba R, seeing
an average savings of approximately 1.5 seconds per kilometer. However, the long-sleeve Gabba R isslightly slower here, by about 2 seconds per kilometer. At this point, we can conclude that the Gabba RJacket demonstrates excellent aerodynamics, close to the performance of the Sanremo speed suit, butvery much dependent on the rider, position, and speed.

G A B B A

With the infinite number of variables in this test, we don’t consider it a definitive test; however, theresults are reasonably consistent and the numbers seem to give a clear indication that the clothing
made a measurable difference.

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T E S T R E S U LT S

C A S T E L L I - C Y C L I N G

G A B B A

RW H I T E

P A P E R5T E S T D ATA∙∙∙∙Wind Tunnel: Polytechnic University of Milano (Polimi)
Date: March 13, 2024
Rider: Kasper Asgreen (Soudal Quick-Step team)
Bike: Road bikeC A S T E L L I - C Y C L I N GTESTING ROUND 3: WIND TUNNELWith the first two tests showing that the Gabba R Jacket is faster than the Sanremo BTW suit alone, we
conducted a further test with professional rider Kasper Asgreen, who has been testing the Gabba R on theroad since December 2023.
The first three runs directly compared the Sanremo BTW suit with the short-sleeve Gabba R and thenthe Gabba R Jacket. For these tests, we did all runs with the Bolero base layer underneath the suit andthe jacket to replicate the conditions of an actual race. Additionally, Kasper used a very aggressive
low and aerodynamic position, as he would at peak times during a race. In these conditions, the shortsleeve Gabba R was slower than the speed suit, showing an approximately 2% higher CdA, which would
translate to a 0.5%-0.7% slower speed on the road. With the long-sleeve jacket, the CdA worsens by
about 4%, which would mean about a 1%-1.5% slower speed on the road. The combination of Kasper’s
shape and position, possibly together with the influence of the Bolero base layer, show a slightly different
result than previous tests. However, we interpret these results as a confirmation that an essentiallywaterproof, fully windproof jacket can nearly match the aerodynamics of a road speed suit.
As a final test to better understand the aerodynamics of the Gabba R, we had Kasper ride in a “normal”
position: hands on hoods, arms mostly straight. In this position, we replicated the results of the first tworounds of testing and saw the Gabba R testing faster than the Sanremo BTW.

G A B B AR
W H I T E
P A P E R

Kasper Asgreen in his super-aero position (solid outline) and his normal position

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AERODYNAMIC DRAG (CdA)
C A S T E L L I - C Y C L I N G

40 km/h			50 km/h
Sanremo BTW

0,252 			0,247

Sanremo BTW w/ Gabba R

0,257 			0,254

Sanremo BTW w/ Gabba R Jacket

0,263 			0,256

Sanremo BTW (up position)

0,346 			0,337

Sanremo BTW w/ Gabba R (up position)

0,341 			0,335

0,360

0,340

0,3200,3000,2800,2600,240
40 Km/hSanremo BTW w Gabba R Jacket

W H I T E

Sanremo BTW w Gabba R (up position)R

Sanremo BTW (up position)

Sanremo BTW w Gabba R

G A B B A

Sanremo BTW

50 Km/hP A P E R7