Rab Cinder Borealis jacket review

The Cinder Borealis jacket from Rab is designed to help keep the wind out on chilly days in the saddle, without stifling you in the process.

Its thin, lightweight construction means it can be stashed in a pocket or packed away easily enough.

The well-tailored fit helps ensure the Cinder Borealis works well when riding, covering your arms, wrists, lower back and neck nicely, even if you’re constantly moving about while descending.

It’s designed to be wind-resistant and it’ll handle a chilly gust well, especially through changeable autumn and spring weather, where it really comes into its own.

However, should the rain come pouring in and the temperature drop, you’ll want something a little thicker to keep the cold out.

Rab Cinder Borealis jacket construction details

Rab offers the Cinder Borealis jacket in five sizes (XS-XL) and four colours.

It’s constructed from Rab’s stretchy Matrix nylon fabric, which gets a fluorocarbon-free DWR (Durable Water Repellent) coating to help keep light rain showers and puddle splashes out.

The tailored cut helps ensure there’s not a lot of excess material left flapping about once it’s on, with a relatively tall neck that adds protection from the cold.

A dropped tail at the rear prevents spray covering your lower back. This can be cinched in using the elasticated draw cord, which sits discreetly inside the hem.

There’s also silicone print inside the rear of the hem to help keep the back of the jacket where it’s supposed to be.

A single zipped pocket at the rear doubles as the jacket's stuff sack should you need to ball it up and stow it in a pocket or backpack – it’ll pack down just a little bigger than an orange.

Rab Cinder Borealis jacket performance

I rode the Cinder Borealis jacket in a wide variety of conditions, ranging from dry, mild autumn days through to chillier, windier excursions when the weather was changing continually.

While most testing was done on a mountain bike, I also used the jacket to commute in on the road in lighter rain showers.

In use, I found the Cinder Borealis to be true to size and I really appreciated the tailored fit when on the move. I can’t stand jackets that balloon up as soon as you start pedalling.

The fabric is soft to the touch and felt comfortable against exposed forearms when paired with a short-sleeve MTB jersey on milder, breezy days.

It’s not sticky or noisy, as some can be, so even if you do warm up and start to sweat, things remain comfortable on the inside.

It helps that it feels reasonably breathable, too. I kept it on for some long uphill slogs and didn’t get too sweaty in the process.

On chillier days, the high neck is a real plus and does a good job of keeping the cold drafts out.

Similarly, the extended back offers ample coverage to keep your lower back and a decent amount of your backside covered when sat down and pedalling, which is handy when the trails are peppered with puddles.

Wearing it on colder days when the weather could change quickly, I was impressed by how well the Cinder Borealis managed to keep the cold out, considering how thin and light it is.

It’ll handle a light shower and offers a decent barrier against the elements when the temperature drops.

That said, the Cinder Borealis wets out pretty quickly in heavy rain.

Of course, that’s to be expected because this isn’t a thick waterproof jacket. And to be fair to Rab, I only really ever struggled with my arms feeling cold on really wet rides, while my torso remained pretty well insulated.

That means the Cinder Borealis has limitations. While it’s a great addition to your MTB kit bag for cold autumn or spring rides, you’ll want something a little thicker and more weather-resistant for the middle of winter.

Finally, I’d love an extra pocket on the front. The rear one is useful for light and small items, but not particularly easy to reach.

Rab Cinder Borealis jacket bottom line

The Rab Cinder Borealis jacket is a great bit of kit for colder autumn or spring rides.

Its tailored fit works well on the bike, it’s light and packs down small enough to not get in the way when you need to carry it and, most importantly, it does a decent job of keeping the cold out.

As you’d expect, it’s best suited to dry days in the hills. If you get caught in a heavy downpour, it won't do a whole lot to keep you dry, meaning you’ll need a second, waterproof jacket if you’re looking to head out into the wilderness.

However, for those days when the weather changes quickly and there’s a chill in the air, the Cinder Borealis is a lovely jacket to have.