As the speeds and technical difficulties involved in mountain biking have cranked up in recent years, so has the need for helmets that offer additional protection over an open lid but without all the bulk of conventional full-facers. Kali Protectives has joined the ranks of those with breezy but tough offerings with their new Invader full-face helmet.
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Sitting at a very respectable £170, the Invader manages to undercut much of the competition, coming in almost a full £100 under the (excellent) Troy Lee Designs Stage I’ve reviewed in the past. Much like that helmet – and Fox’s similarly priced ProFrame – it’s got a fixed chin bar, something Kali reckons is vastly preferable to a convertible design as space not taken up by a release mechanism can be used for foam protection instead.
What are the safety features?

While the Invader undercuts much of the big-name competition, Kali says it hasn’t scrimped on safety to get the helmet to this sort of money. It doesn’t have any big-name features such as MIPS, it does have a whole host of safety features of Kali’s own devising, with two different densities of foam to better absorb energy from an impact, plus a feature they call the ‘Low Density Layer’ or LDL.
This is basically a series of inserts with features shaped a bit like the sucker on an octopus tentacle made from a viscoelastic foam – the sort of stuff used in soft shell kneepads. It’s claimed to help both reduce low-level linear forces as it compresses, but also reduce the rotational forces transmitted to your brain, much like MIPS.
There’s a breakaway peak with three positions and the strap uses the quick and simple magnetic Fidlock closure, making it easy to get on and off with a single, gloved hand.
How well ventilated is it?

When it comes to the all-important ventilation, the Invader is off to a good start, with a substantial 35 vents covering the lid.
There are only two shell sizes on offer, with a XS-M helmet that covers from 55-58cm and the M-XL lid that ranges from 58-63cm. The fit is tuned by switching out the individual cheek, neck and top pads with a pick of three different thickness alternatives that are included when you buy. All the pads are machine washable and antibacterial.

On a short test ride on a relatively chill day, the Invader performed well, even when compared to an open lid. Of course, more riding is needed in warmer weather, but the airflow seemed to be good when moving, though inevitably it felt warmer than a normal lid when static.
What’s the fit like?

It’s a truism that some helmets fit certain people better than others, but the Invader was a bit of a mixed bag amongst the people that tried it on. Some of this is inevitably down to the relatively limited size range – two shells for XS all the way to XL is quite the stretch when Troy Lee uses three basic shell sizes and Fox have four from which to start pad tuning from – but this is the compromise for an affordable asking price.

Personally, I get on well with the shape of the Stage and relative to that, the Invader feels a little bit less spacious around the chinbar and front vent and tended to squeeze my cheeks a fair bit when getting it on or off. Some other people found it rather spacious at the top compared to elsewhere, but that wasn’t too much of an issue for me.
At first, the LDL suckers at the rear of the lid were rather noticeable, but when I actually started riding they didn’t dig in and as I rode, the cheek pads became less noticeable and I reckon these would start to conform over time, though the pad material isn’t as soft feeling as the higher-end lids I’ve used.
All in all, it’s a promising helmet for those that want to race – or just ride – with more protection than standard but don’t want to compromise too badly on ventilation or pay an awful lot of money. I’ve got a helmet for long-term testing, so check back for a full review soon.
