Giro Synthe aero road helmet launched

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Giro today launched its latest and arguably most performance-oriented road helmet to date, the Synthe. Claimed to be 13-percent lighter and even slightly faster (in some conditions) than the current Air Attack, and yet slightly better ventilated than the ultra-cool Aeon, Giro says it's 'the one' helmet that's suitable for all conditions, all the time.

"It's the helmet if you're interested in all-around efficiency - cooling, aerodynamics, ventilation," said Giro senior brand manager Eric Richter.

The one metric that Giro doesn't toss out there, though, is the one that we'd argue is most important to riders who simply weren't interested in the decidedly polarizing Air Attack. By our estimates, the new Synthe is easily 114-percent better looking with surprisingly classic, hairnet-like lines and a sleek, low-profile aesthetic that's not only inoffensive but actually manages to look good by drawing features from the Aeon, Air Attack and Aspect. We measured a small Synthe to be nearly 10mm narrower than a comparable Aeon.

It's also impressively light at just 250g (claimed) for a CPSC-approved size medium (CE versions will be closer to 230g), plus there are dedicated slots to stash your sunglasses (and they actually work).

Retail price will be US$250 / £200 / €250 when it arrives in stores in December with three available sizes and eight different color choices.

The numbers story

Giro says that testing in multiple wind tunnels has shown the Synthe to be its fastest road helmet in typical riding situations: with the helmet at a 30-degree angle from perfectly upright and in wind-averaged conditions that take a wide range of wind angles into account (although the Air Attack is apparently still faster in a more aggressive, 'head down' position).

Moreover, Giro says the Synthe is faster than the Specialized S-Works Evade by a difference of about 8g of drag at 40km/h.

While the biggest contributor to the Synthe's aero performance is its smoothly tapered shape, the helmet's unique Aero Mesh side panels further alleviate drag. According to R&D director Rob Wesson, those panels control the so-called boundary layer and provide a smooth pathway for air to escape that doesn't excessively trip up the external airflow like fully exposed side vents.

Giro also says its in-house 'Therminator' instrumented head form shows cooling power almost exactly on par with a bare head.

First ride report

We did just one ride in the new Synthe, but it was in the stifling June heat of the Arizona desert.

Our first impression was certainly the surprising appearance. While it looks good in pictures, the Synthe looks even better in person.

Ventilation was also remarkably good with excellent flow-through and plenty of open ports for heat to escape when you're just sitting at a stoplight and sandwiched between the oppressive sun and hot tarmac.

Giro admits that there's still a little bit of work to be done on the fit and finish but overall, the Synthe essentially disappears on your head. The height adjustable Roc Loc Air retention system helps suspend the helmet's shell just off the top of your head and the fully circumferential contact does a decent job of distributing pressure - although we were still happy to hear that the brow pad section will ultimately be taller for production.

Giro says sponsored teams will use the Synthe in the upcoming Tour de France and we'll have proper production samples for long-term test in about 30 days so stay tuned for more. So far, though, we like what we see.