off-road.cc

We've given Evoc’s Seat Pack Boa L a thorough testing over six months. It’s really easy to mount so it doesn’t waggle, at 3L it holds the perfect amount of stuff for a good day out, and it's waterproof with the added bonus of acting as mudguard. Unfortunately, all the good work is undone by a design flaw that can see the whole bag fail.

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The Seat Pack Boa is so named as it swaps the classic Velcro strap around your seatpost for a BOA clamp, plus a specially-shaped wedge of soft TPE (thermoplastic elastomer) to protect your post.

It works really well, even if the strap doesn’t always sit perfectly aligned in its angled slot. The seat rail straps are the traditional Velcro design, and once done up tight the whole bag stays put with little to no waggle.

Unfortunately, these straps are the source of the bag's problems. The big fly in the ointment, and it’s a big old bluebottle, comes where the straps slot through fabric. The bag is starting to tear under the strain – which is unexpected given the obvious need for strength here, and especially given the bag's price.

We spoke to Evoc, and they are aware of this issue; they're actually in the process of updating the design for the next production run. We’ve also spoken to Zyro, who distributes the bags in the UK, and they say affected customers should contact Evoc customer service for a replacement.

We'll update this review once we get the redesigned version, and let you know if the fix has worked. I hope so, because until this potentially ride-ending and bag-ending issue cropped up, there was much to recommend about the Evoc.

Inside the bag you find not one but two types of stiffener, both starting at the seatclamp. The upper and lower ones are a single sheet of plastic riveted to the far end and slotted into little guides inside the bag’s roof and floor. This stops it sagging and makes it easier to pack.

Meanwhile, the sides have a spider-webbed stiffener which gives further shape and saves a few grams over more solid sheets, for those counting.

The closure is a little unusual, as it folds in a X shape (note the Velcro tabs to assist) before rolling up in the normal way. It then secures with an overly fussy but effective buckle. It all works very well, though the Velcro can catch clothing and stop or even damage it as you pack.

Evoc says it's waterproof, and I certainly had no leaks during my long test.

It's a useful size. The bag easily holds a jacket, tubes, tools, a pump and food with room to spare. There are no extra mounts on this outside, as it’s really not meant for more than a day at a time – and given the issues with tearing that's probably a good thing. A light mount would have been nice, though.

We measured it at 230g against a claimed weight of 225g – a difference which is neither here nor there – and it's at the lighter end of seatpacks for this 3L size.

It’s not cheap though at £125. Apidura’s Racing Saddle Pack is also £125, for instance, but that's two litres larger and actually lighter at 210g. It also has a light loop and reflective detailing.

Ortlieb's Saddle-Bag Two is perhaps the nearest rival in 4.1L guise, but that costs £45 and has its own unique mount, a light mount and reflective details. It's 30g heavier than the Evoc at 260g, though.

Overall

The Evoc Seat Pack Boa L is waterproof, a very useful size and really secure on the bike. Despite a few niggles with awkward Velcro placement and the lack of light loops or reflectives, it's a pleasure to use – unless it starts to rip.

Unfortunately, this falls well short of the quality you expect at this price. It appears to be a massive oversight in product testing, and one I hope Evoc properly fixes with its redesign. While that version could easily be great, thanks to the performance of the rest of the bag, we can't seriously recommend this flawed design as it is.

• www.evocsports.com

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