off-road.cc

The Ergon BP1 Protect is a lightweight pack with storage for the essentials, and though it works and looks like a backpack, it's also a back protector. Slim enough to wear under a jersey as armour and (just) backpack-y enough to be worn above, it offers reassuring protection – though disappointingly the handy 1.5L reservoir is an extra cost.

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At just over 500g, the BP1 is pretty light, and it's certainly slim. It's built around the BP100 protector featured in several other Ergon packs, which is a soft, three-layer foam that bends easily to conform to your back. Legally speaking it conforms to CE EN 1621-2 (Level 1), which is a common standard in mountain biking, and worth having as it's actually a rating for motorcycle armour. Level 2 is more protective still, but Level 1 is still entirely useful.

The well-placed BH150 1.5L reservoir sits low and squat for a stable feel – at least, it does if you buy it at extra cost. A mesh cover holds it steady and it’s clipped in securely, while the hose routes cleanly up the back and down your left or right strap. The clip on the elasticated sternum strap could be better, however, as the hose can sometimes break free.

Either side of the reservoir are two zipped pockets; room enough for money, snacks, keys, tools and the basic kit for short rides or bike park laps. I felt most comfortable with it over a baselayer and under a jersey.

The BP1 is very adjustable and sits differently on the body to a regular pack, and it’s worth spending time with the adjusters getting it right, for obvious reasons. Ergon do two sizes, and each one has five levels of adjustment, so it's easy to tailor quite accurately. When fitted well, the BP1 is stable on the back, with the bladder position making it comfortable and minimising movement on rowdier trails.

The BP1 is aimed at downhill and gravity riding – and that's absolutely right. But I also found it pretty confidence-boosting when facing something challenging on more normal trail rides, and given its ability to carry water and spares, it's easy to take with you.

The BP1 Protect is a good blend of pack and protector that will appeal to those who ride light but hard. It's a shame the 1.5L bladder isn't included in the price, and the hose clip needs improving, but beyond that – and competition from Ergon's own bigger packs featuring the BP100 – there's little not to like if this slim, light little creation fits your niche.

• ergonbikes.com

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