Cycling Weekly – July 25, 2019

46 | July 25, 2019 | Cycling Weekly

TECH GROUPTEST

Five wind-cheating

lids for longer rides

tested and rated

Aero road

helmets

WHAT

It is easy to make a rider’s head into a

more aerodynamic shape by enclosing

it in a teardrop-shaped fairing — a time

trial helmet, in other words — and it’s

also easy to keep a head cool with

multiple vents. But how do you

combine the two for longer road rides

where watts need to be saved but

overheating needs to be prevented?

Th e big helmet brands each have

their own approach. Most have been to

the wind tunnel and have data to back

up their watt-saving claims, while each

modern aero lid also has its own

confi guration of strategically placed

intakes and slots to channel air over the

top of the head.

WHY

Th e number of watts that can be saved

via a well-designed aero helmet is

considerable since the head is large and

unaerodynamic. For pro teams looking

for every advantage, an aero helmet is a

no-brainer, while sportivistes on an

all-day ride could be saving minutes.

HOW

We don’t claim to have conducted

independent wind tunnel tests on these

helmets and besides, what’s fastest for

one rider in the real world might not be

the fastest for the next. In addition,

wind tunnel testing doesn’t take

account of useability, comfort and

convenience. So our Tech team have

simply used these helmets for riding

and racing and rated them according to

their impressions — including fi t,

durability, build quality, weight and

aesthetics, versus their price.

Met Manta £179

Giro Vanquish MIPS £219.99

Giro created the wind tunnel-

developed Vanquish to be the perfect

compromise between a typical

ventilated road helmet and an

aerodynamic TT-style helmet.

The split-shell design is called

TransformAir: the step-down tricks air

into behaving as if the helmet has a

teardrop shape but allows for a shorter,

more practical tail.

Four forward-facing vents pull cooler

air over your head while six at the rear

expel warm air and regulate head

temperature. In practice these actually

do a very effi cient job despite the

normal restrictions with a helmet

of this type.

Inside, Giro has employed the

latest MIPS liner that’s made of a

much more breathable material than

previous versions and has no noticeable

negative impact on fi t or comfort. It also

incorporates Giro’s long-standing RocLoc

retention system and antimicrobial pads.

A neat magnetic visor with Carl Zeiss

optics is more suited to TT duties,

snapping into place perfectly every time

thanks to three strong magnets. When

not needed, it can be fl ipped and

clipped to the helmet using the

same magnets.

It feels fast and we pulled

up several Strava PRs, but

we are just not sure

about its horseshoe

crab (google it)

appearance.

http://www.zyrofi sher.co.uk

Weight

300g

The Met Manta is one of the original aero

helmets and was worn, endorsed and

won in by Mark Cavendish until

2018. It earned a place on our
      Editor’s Choice selection in 2017 as
      well as holding a continuing position in
      Met’s range.
      The Manta looks relatively
      enclosed from the front with
      its two front slot vents, a couple more
      on each side and another one around

halfway along the helmet’s crest.

At the rear, six vents let warm air

escape. Inside, there’s a complex

pattern of ribs and ridges to direct

air across the top of the head. Even

the rear cradle fi ts close under the shell

to keep it out of the wind.

The vents work well to channel

air over the head. In particular, the

side vents keep the temples cool

where heat can build up. Overall, the

Manta is not hot in use.

It’s light for an aero helmet too and

this, combined with its good venting and

Safe-T Advanced micrometrical fi t system

— which uses large surface area

contact points to enhance

comfort and keep the weight

low — means it’s a versatile

daily-use helmet.

http://www.met-helmets.com

9

8

Weight

215g

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