Lazer Cosmo helmet with Aeroshell

The Lazer Cosmo helmet with Aeroshell is a road helmet that comes with a cover – the Aeroshell in the name – to improve aerodynamics when you don't need as much ventilation or are prepared to sacrifice ventilation for a tiny bit more speed. It does a great job both with and without the cover, and with the shell on it will keep the rain off your head too.

If you do a little bit of time trialling but can't really justify buying a dedicated time trial helmet helmet, then this could be the answer. Lazer bill the Cosmo as their 'most advanced road helmet to date', and as you'd expect from that designation, it's expensive.

The fit and comfort of the Lazer Cosmo helmet is much improved from Lazer's cheaper models, thanks to the upgraded extra light version of the Rollsys cradle. This is the wire system that secures the helmet on your head and is adjusted via a top mounted screw. It is a much nicer fit, with soft, lightweight straps.

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I have a small head and often have helmets at their tightest setting. On the Lazer I find the screw for holding it tight loosens sometimes. If I compare it to the Kask Mojito with its dial at the back, the Kask mechanism feels more secure to me, but riders with larger heads will probably be fine.

There is a little bit of adjustment to be had by lowering the wire system to fit round the head more at the back, so it doesn't feel like it is perched on your head. It is a small adjustment but quite useful for small heads.

There isn't a lot of padding, but it seems the right amount as the Cosmo is not uncomfortable at all. Less padding also means less sweat getting soaked up and needing to be squeezed out. It comes with spare set of pads in box.

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Ventilation using it as a road helmet was very good. It has deep channels that carry plenty of breeze over your the head. Put the aeroshell on and you lose ventilation. The cover clicks on with no additional fixings and blocks all the inlet vents, leaving just a few open at the back. It gets a bit warm under the shell, but it you are wanting to shave seconds off a 10 miler, then it's probably worth the extra sweat.

One of my test days was a 10-hour ride on a warm day, and the Lazer Cosmo performed really well for ventilation and comfort. I really didn't notice it as there were no pressure points. As someone with a small head, finding a helmet which is a comfortable fit is sometimes a challenge. But this helmet passed the test well, especially on a long ride. Right amount of padding, soft comfortable straps which fit well. And it doesn't look like a mushroom on my head as some do.

Overall, a comfortable lightweight helmet with option of click on aeroshell. If you are looking to colour coordinate with your bike there are many different colour shells, and a union jack one.

Given that it costs £219 and weighs 255g, whether you the Cosmo is for you depends on comfort, and whether the aeroshell is of any use to you. There are lighter helmets at a better price like the Kask Mojito or the Ekoi Corsa Light with shell.

If you need a new helmet and fancy the idea of a few time trials then the dual-use Lazer Cosmo could be a good option.

Verdict

Great dual-use lightweight helmet that swaps from road use to aero with removable shell, but on the pricey side