Walking with it, I haven’t found it restrictive at all. Instead, it seems to move naturally with your body and stride, rather than against it. There’s very little sway or bouncing, even when moving quickly over rough ground, and the vest-style harness helps the pack feel almost anchored to your torso. On uneven terrain especially, it moves with the natural rotation and rhythm of your gait rather than feeling like a separate weight shifting around behind you. It’s an aspect of the pack that has hugely impressed me.

I haven’t noticed any pressure points at all from the Syclon, something that isn’t always the case with packs with suspended back systems.

Fit

One big downside with the Syclon XP is that it only comes in one back length and it doesn’t have any adjustment to cater for longer or shorter backs. Fortunately, for me, it was absolutely perfect and felt almost like a custom-fit design on my 19-inch back, but I do think it might not work for people with particularly long or short backs. Likewise, while female and narrower bodies are catered for by the ND versions, I’m not sure it will work for larger bodies as the hipbelt fins might end up a little short.

Waterproofing and Durability

On my Dartmoor hike, where I had the pack heavily loaded, I did have some concerns that I might sustain a puncture to the main fabric as the pack was bulging and the 40D fabric does have quite a thin feel to it. It feels very similar to a fairly thick tent flysheet. Fortunately, I didn’t have any issues on that trip, even after plonking the pack down repeatedly onto hard and rocky ground, and there have been no issues since. That being said, I do think it needs to be treated with a touch of care. A sharp branch, a bit of very rough gritstone or a rogue tent peg could, I think, do some damage.

The waterproofing, I’m pleased to say, has been up to scratch. I’ve hiked through some wet days with this, including one day where I was faced with wind-driven rain in North Wales, and I’ve felt confident that my kit will remain protected. I have found, however, that you do need to ensure the roll-top is done up tightly as you can get some gaps if the pack is stuffed very full.

Features and Storage

There’s a lot of very useful storage. I really like the big dump pocket across the front of the Syclon; it’s the right size for your waterproof layers or a chunky down jacket. It’s not made of the same stretchy mesh that you often see front stash pockets made from and instead it’s made from a durable nylon. I personally am not too big a fan of mesh pockets as they can snag and tear quite easily, so I like Rab’s approach here.

The side pockets are similarly well thought out, with gusseted panels that add a surprising amount of volume – easily enough for a Nalgene flask. You can reach around and grab a bottle without taking the pack off, although getting it back in one-handed is much trickier.

There are zipped stretch pockets on the hipbelt and each of these is big enough for a big bag of sweets. On one shoulder strap there’s a mesh dump pocket that’s ideal for a 1-litre soft flask and on the other there’s a zipped mesh pocket that’s ideal for a phone, GPS, radio or energy gels. I actually found that it handily caters for an OS map too.

There’s one more pocket on the pack itself, tucked away between the harness and the main compartment. This is surprisingly big but it shares space with the main compartment, so if the latter part of the pack is fully loaded, getting things into it can be a bit of a squeeze. Still, it’s ideal for a hydration bladder and you can also keep wet items in it without risk of any seepage into the rest of the pack. Rab say that it’s a good place to store your wet rain gear but I’d say the front stash pocket is the best place for that kind of stuff.

Trekking poles can be attached via loops and straps either side of the front of the pack. The side pockets are also big enough and durable enough that they can easily be stored in them too.

How it Compares

The obvious comparison within Rab’s own range is the Muon. In many ways, the two packs feel very closely related: both are lightweight, streamlined and aimed at fast-moving hikers who like to keep their kit list fairly dialled in. The key difference is that the Muon sits closer to your back and has a more traditional foam back panel, whereas the Syclon XP uses a suspended mesh system to maximise airflow. That immediately makes the Syclon the better option for hot-weather hiking and long sweaty days where ventilation becomes a priority. The Muon, however, probably has the edge for scrambling and rougher mountain terrain because the load sits slightly closer and feels a touch more precise when moving dynamically.

The Veil sits at the other end of the spectrum. That’s much more of a running and fastpacking pack, designed around very light loads and high-tempo movement. The harness design on the Syclon XP definitely borrows heavily from the Veil, particularly in the way it wraps around the torso, but the Syclon feels noticeably more substantial and supportive under load – and again, it has that ventilation across the back.

Outside of Rab’s line-up, the closest comparison is probably something like the Ultimate Direction Fastpack series or the Montane Trailblazer. Both of these blend running vest comfort with hiking pack practicality, and the Syclon XP occupies a very similar space. Again though, the Rab feels more refined as a hiking pack.

It also has competition from the range of Dyneema packs these days, one example being the Hyperlite Mountain Gear Waypoint. The main difference? Price. Dyneema packs come in at around £300 while this is priced at £160.

Verdict

The carry comfort and stability that the Syclon XP offers are truly excellent. It’s a very comfortable pack that, despite its diminutive weight and construction, handles loads well. The waterproof material is a huge bonus to have and the assortment of pockets adds to its overall convenience.

Its 40L volume, for me, makes it very well suited to thru-hiking, with enough space for all the essentials and room to spare for any extra meals (or a couple of small luxuries) you might want to carry. If you don’t really take an ultralight approach when backpacking, or you’re going a long way off the beaten track for multiple days and consequently need a lot of space for food and drink, then it might be a little on the small side in terms of volume and you should look into something bigger.

I should also point out that the suspended mesh back panel does make it more suitable for warmer weather. In winter, that ventilation might not always be appreciated and it’s also a place where wind-driven snow can build up quickly.

Weighing up the 30L or the 40L? The compression straps and the roll-top both allow you to really minimise the pack around the load you’re carrying, meaning it works perfectly well as a daypack. So I’d recommend the 40L as it can do the job of two packs.

All in all, the Syclon XP is a smart pack that is perfectly tuned for the trail. I’ve only used it for one-night campouts so far but it’s absolutely nailed on for my next backpacking trip.

Where to Buy

Rab Syclon XP 40 review

Our tester’s verdict: “Supremely light but with enough space for lightweight backpacking set ups. It also has high levels of ventilation while still providing a very stable carry.”

Check 40L price at Rab
Check 30L price at Rab