Review – 2018 Fox Flux helmet

A full overhaul for one of the original trail lids

For 2018 Fox has revamped its Flux helmet completely. With the original Flux being a standard setter does this new model still impress us with its design details, FIT AND protection?

Words: Sean White  Images: Callum Philpott

If you were looking to buy a helmet for trail riding back in 2006 then there’s a strong chance that the original Fox Flux helmet would have been on your list. It was one of the first helmets to move away from the concept of simply taking a road helmet and making some revisions to it. Adding a peak to an aero style road design, slapping on some new graphics and colours was the route many brands took. It’s no surprise that many of us were riding trail bikes in a skate or BMX style ‘piss-pot’ lid back then.

Fox saw this and when the Flux helmet was launched it had little competition, with only the more expensive Giro Xen as one of the few other options. The Flux was a hit for us and soon took a place in the Dirt 100 – it became our ‘go to’ choice for trail riding.

‘The Fox Flux trail lid has been around for some time now and it has definitely become a bit of a classic in our eyes’ – 2014 Dirt 100

In 2018 we are spoilt for choice, with most established brands and a few new comers offering a sorted helmet for trail riding. The safety these helmets provide has improved, with more technology, deeper coverage of the head and improved retention systems. Fox reacted to this two seasons ago with the Metah – a design that was up to date in nearly all (but not every) area of helmet design. However, the Flux was still in the Fox range and had become one of its best selling mountain bike products. This helmet design (shown above) was right from the start, with styling and detailing that has stood the test of time.

But technical trail riding has now blurred into the world of enduro racing, bringing with it the need for even more protection, as well as requirements such as goggle compatibility and increased stability. It was time for an update. With two years in development by the same design team who gave us the lightweight and well ventilated Fox Proframe full-face lid our expectations were high.  Here’s a full run down on the 2018 Fox Flux.


Fox offer the new Flux in two models – a high spec model with MIPS protection at £115 and the standard model with a lower price of £80. Three sizes are available, XS/S, S/M, L/XL (covering 53cm – 62cm measurements) and as always with Fox, this lid has plenty of colour options – solid colours or the ‘Drafter’ multi coloured models. These will complement the current Fox MTB clothing range if that’s your thing. We’ve been testing the Flux with MIPS in a size S/M (55-59cm).

‘Our goal with the redesign of the Flux was to maintain the original feel of the helmet which made it such a success in the sport. It was recognised and reviewed as one of the most comfortable helmets in the market while adding the coverage aggressive trail riders demanded. We have taken those qualities and improved in nearly every area of performance with the new version’  – Dave Ahumada, Fox


With relatively deep back and side coverage, the older Flux model provided reasonable protection for a realistic weight. Ventilation was good too, as was the styling. This was a great blueprint for the new design. So, what are the major improvements?

The shell of the new Flux is not just a different shape but as with Metah helmet uses Fox’s new helmet technology – Varizorb. This is an impact reduction system, which uses multiple densities of cone shaped EPS foam in strategically designed layers. Fox suggests that Varizorb provides superior protection without adding bulk or weight. There is an internal cage (a feature similar to that used on the Fox Proframe full-face lid) that is intended to hold the helmet together on a major impact. One are Fox was keen to focus on when rethinking the Flux was coverage of the head. This new version sits low around the ears, sits low at the rear of the head and feels stable and secure when adjusted correctly.

It’s a well-finished helmet, with a micro-shell that covers the inner rim edge, adding to the long-term durability. The styling has hints of the original design. The high rear end has a slight rise that echoes the spoiler of the original Flux. Although tall at the back, this new Flux has a lower profile shape than the Fox Metah and with the deep rear coverage has a good fit (for those of us that tested it) and excellent stability when the terrain turns rough.

The well designed retention system plays a key part in the fit, comfort and stability of this helmet. With 300° of your head covered by this adjustment system we found no ‘hot spots’ or discomfort. There are two horizontal settings and three height positions, with solid push in studs that don’t shift unnecessarily, something we have found with adjusters that slide into position. The rear cradle sits low on the head and the tension dial feels solid and is easy to use when wearing gloves. Once adjusted, the Flux stays in position and caused us no frustrations in terms of fit or comfort.

The higher spec Flux has added MIPS (Multi-directional Impact Protection System) slide-plane tech safety protection (read about this HERE) along with quicker drying anti-bacterial X-Static liner pads and a magnetic Fid-Lock strap buckle.

Ventilation is good, with 14 large vents keeping air flowing through the helmet. The front three vents work with the peak design, so wherever this is positioned cooling is not compromised. There are three additional front ducts below the brow of the helmet; these look like they are there to direct air in above the frame of goggles. We’ve not ridden in warm or hot weather yet but on hard efforts comfort has remained high.


The peak is a departure from the norm and quite the opposite of the integrated (and fixed position) design seen on the Fox Metah. Made of a flexible plastic material the Flux’s peak feels a touch flimsy at first but is designed to flex on impact rather than act as a lever and shift the helmet further out of place. With goggle wearing riders often liking to park their eyewear below a pushed back helmet peak, Fox has given the Flux the widest adjustment range for a peak that we have seen. On our test helmet we found that careful adjustment of the two pivot screws was needed for the peak to move through its pre-set positions as the flexible nature of the material meant it could often be left sitting at an awkward looking angle. Once in position it stayed in place and although we had concerns of it rattling on rough terrain we had no problem with this.


Weight is mid pack – our test MIPS sample in a S/M weighed in at 391g (listed at 390g). By comparison a S/M Fox Metah (without MIPS) is 394g and a M/L Endura MT500 is 341g and Giro’s MIPs equipped Montaro (M) is 385g.


The new Flux arrives to a market place full of competition. The Bontrager Lithos and Rally, Giro Chronicle, Endura MT500 and Bell’s new FourForty and Sixer and all sorted designs. Troy Lee’s A1 and A2 lids are always a favourite choice too. We’ve ridden most of these helmets and gravitate towards the models that are comfortable, lights and with few (or no) frustrations in use. So how did the new Fox Flux compare to the class of 2018?

With the testing in January and February it’s been either cold or wet (and no trips to warmer climates…) so we’ll need to update this review once the warmer weather kicks in. However, our initial impressions have been good.

The Flux feels light, like a trail helmet should. It hasn’t that overbuilt feel that some designs have, with a lower profile than the Fox Metah and  great stability. Put it on, tweak the adjustment and it stay put – as it should – regardless of how rough the terrain gets. This is an area where we found issues with the bulkier Metah, with the front of the helmet dropping down on rough descents. We had concerns over the flexible peak – we can see that under impact that the flex is potentially a good thing – and found the adjustment not as slick as others helmets. The range of movement that the peak can arc through is great though and once adjusted stays in place.

‘Ventilation was very good. Our benchmark trail helmet for airflow is the Specialized Ambush, so we’ll be comparing the Flux to this lid when the summer rolls in’

The detailing and finish are up to the usual Fox standard and the magnetic FidLock strap buckle was both easy to use and a feature we’d like to see on more helmets. Goggle compatibility has been considered and is better in some ways than on the Metah. The peak arcs high enough to park goggles under for a climb and our test goggles sync’ed well with shape of the Flux. Although there is no real retention buckle or gripper for a strap, the strap can be placed around the rear of the helmet without interfering with the exhaust vent. With a silicone inner of the strap the googles stayed in place. The X-Static pads on this MIPS version dried quickly (bear in mind we were mostly riding in sub 10°C temperatures) and Fox supplies a spare set as part of the package – a nice touch.


Fox has taken a much loved design and given it a major overhaul and making the new Flux bang up to date. Protection, comfort, adjustment, stability and ventilation are all areas that have had plenty of attention and the result is a trail helmet that compares well in both performance and pricing to our current benchmarks.

PRICE: Flux £80, Flux MIPS £115

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