Fox Defend Fire Bib Pants review

While certainly different, the Fox Defend Fire Bib Pants are a marriage between solid performing winter-focused trousers and bibs. As a result, they’re pleasantly warm in cooler temperatures, and they offer even more protection against the elements. They’re comfy, too, though the bib straps could use some refinement.

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The Fire Bib Pants are built with a ripstop fabric, lined with a fleece interior. While that sounds like it’ll get warm quickly, the Polartech insulation claims to be breathable, keeping you from overheating. The exterior of the trousers is then coated with a nice DWR coating to shrug off spray. Closing up the Bib Pants is a simple ratchet, and there’s a zipped pocket at the side of each thigh.

At the back of the trousers, there are a couple of stretchy mesh panels which allows the ankle cuffs to expand around the heel when sliding them on. At first, I expected these to welcome water into the trousers, but in practice, this didn’t occur, thanks to their clever placement.

The standout feature of the Fire Bib Pants is the removable bib. When installed, it bolsters the pant’s storage capacity thanks to two zipped pockets at either side and a larger mesh pouch that can accommodate a water bottle. It’s not all about storage, though, as it provides an extra shield against any back-wheel flung spray, keeping you drier when riding packless.

As I said, the bib straps are removable, and they’re pretty easy to whip off. The straps utilize a range of poppers that keeps them in place, then the back part is simply zipped on. Stretching the straps over your shoulders does require a little care, as the zip can undo a little as the straps extend.

Fox has done a pretty good job with the Depend Fire Bib Pant’s fit, but if I were to niggle, they’re a little tight around the hips. It’s definitely not a game-ending issue, but tightness can be felt when in a wide stance over the bike, like when cornering, for instance. However, I never found it to be a hindrance when riding, but it could well be worth sizing up. For reference, I’m a 32″ waist.

Other than that, the pants have proven to be super comfortable, and the tapered legs leave plenty of room left over for pads. Although, with the bib installed, the straps become a bit of a pain. When wearing the trousers with a base layer, as would be typical, the straps are keen to slip, which can be a proper hassle when wearing jackets. It would be good to see some grippy silicone here, but the bib, thankfully, isn’t an integral feature of these pants as they run perfectly fine without. It’s a welcome feature, though, especially if you’re not one who usually wears bib shorts but wants extra protection and pockets.

The most surprising aspect of the Fire Bib Pants is how well the Polartech insulation works, not only to keep you warm but cool too. I’ve worn these trousers down to 1° and up over 10°, and they’ve remained totally comfortable at both ends of the spectrum. Granted, I wouldn’t want to don them far into the spring, but if you’re looking for one pair of trousers that’ll keep you happy through sub 15° temperatures, the Fire Bib Pants will do just that.

Upping the weather protection game is a rather impressive DWR coating. While I’ve not had the chance to test these during some serious downpours, they have seen their fair share of deep puddle splashes, and when paired with my Five Ten Trail Cross GTX shoes, my bottom half has remained perfectly dry. Though, of course, to stay waterproof, the coating will need a top-up down the line, but after a good handful of washes, it’s showing no signs of giving up just yet.

£180 is quite a chunk of cash to throw at a pair of trousers that you’ll probably only wear during the winter, but the detachable bib makes them rather unique against regular trousers. Similar garments come in the form of POC’s Consort MTB Dungaree which will set you back a hearty £450.

Let’s look at something a bit more traditional in style. The Endura MT500 Freezing Point trousers are £30 more expensive than the Fire bibs, at £150. Although built especially for seriously cold temperatures, using Primaloft Gold Active Insulation, Endura’s pants lack the bib element and additional storage that come with them. 

The Defend Fire Bib Trousers from Fox have proven themselves to be a sorted pair of bottoms for riding throughout the winter and into the beginnings of spring. They’re warm when they need to be without getting uncomfortably hot, and aside from a bit of tightness, they’re mega comfy. They fend off the wet stuff surprisingly well, too, though they could do with a bit of silicone on the straps to stop them from slipping. 

• foxracing.co.uk

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