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The 7iDP Project 21 Pro Trail helmet is well-thought-out offering plenty of safety tech to address the impact and rotational forces during a crash. This lid has a range of construction methods that aim to keep you wrapped up in a comfortable and airy package. The sweat management needs some refinement, and I found the helmet a little bulky but represents good value for money considering all the tech on offer.

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7iDP Project 21 Pro Trail helmet - Technical details

The Project 21 Pro Trail helmet is 7iDP’s answer to the perfect open-face trail helmet and it's clear the brand has put a lot of features into it for maximum protection.

Starting with the foam construction, 7iDP has used ConeHead technology to act as a crumple zone during impact. It’s made up of an outer and inner EPS foam with inward-facing conical shapes, which sandwiches a softer mid-layer – this construction is designed to distribute and absorb impact and rotational energy during a crash.

Beyond the foam build-up, the helmet also features Energy Reduction Technology (ERT), which is a separate foam lining inside the helmet. This is a 4mm layer of polymer foam, which adds a layer of protection against linear and rotational impacts, even at low-impact levels.

7iDP Project 21 Pro Trail helmet_5, by Ty Rutherford

The visor is released during a crash to reduce rotational forces and has two preset positions. The padding is minimal and features an anti-microbial liner to keep things fresh. The helmet has two pad sets of different thicknesses to help get the perfect fit.

Finally, adjustment is covered with a Fidlock buckle and a rear adjuster dial with four positions to get it sitting correctly under the cranium.

7iDP Project 21 Pro Trail helmet_2, by Ty Rutherford

The Project 21 is available in three sizes, XS/S, M/L, and XL/XXL, fitting head circumferences from 52cm to 63cm. It comes in three styles, which are all fairly subtle and is covered with a lifetime crash replacement where 7iDP will offer a 50% discount on a replacement.

The tested helmet is the Holographic Ltd Edition Series 1 which features all the same technology but comes in its own unique style and includes a padded helmet carry bag.

7iDP Project 21 Pro Trail helmet_1, by Ty Rutherford

7iDP Project 21 Pro Trail helmet - Performance

Starting with the fit, I’d say the Project 21 fits a slightly rounder head shape. My head is more oblong shaped and I’ve found the fit quite uneven. That being said, with some padding adjustment I got the fit to be comfortable, which included adjusting the height of the dial to sit correctly under my cranium. Although the padding itself is minimal, it does a great job of cushioning the helmet which I think is aided a little by the low-density ERT foam lining. The adjuster dial pulls in evenly around the circumference and having a Fidlock buckle is always a nice touch for ease of use.

7iDP Project 21 Pro Trail helmet_3, by Ty Rutherford

Once on the head, I got the sense the helmet was on the bulky side, however, it doesn’t feel heavy. The design is on the chunkier side but doesn't impact the total system weight.

I found sweat management to not be great on this helmet, the thin forehead pad fills up with sweat quickly and then drips into your glasses, which is less than ideal mid-trail. This can be managed by ensuring the pad isn’t saturated before dropping into a descent. In terms of sunglasses, I had no issues with the helmet shape interfering with riding glasses. There is no dedicated glasses storage but this is not a deal breaker for me.

7iDP Project 21 Pro Trail helmet_4, by Ty Rutherford

The 21 vents do a good job of managing airflow and, although it's not the most breathable helmet, considering the enduro-style shape and size – it does a good job of letting air flow in and heat out.

The visor adjustment is a little odd. It clicks into place but only has two positions, which are very similar to each other.

7iDP Project 21 Pro Trail helmet - Verdict

The 7iDP Project 21 Pro Trail helmet retails at £160 while the Ltd-edition version comes in at £200. While the Ltd edition gets a fancy padded helmet bag, the standard versions represent better value for money. Other options include the £175 Smith Optics Payroll helmet which Liam praised for being very comfortable and packed with safety features. For £150, the Giant Rail helmet is good-looking and gets the latest Mips technology – it's well worth a look. 

The 7IDp Project 21 Pro Trail helmet is an excellent offering featuring a host of safety tech to save you from impact and rotational forces in a crash. It’s a little bulky and the visor adjustment is minimal. However, I found it a comfortable and breathable lid for trail and enduro riding. 

• 7idp.co.uk
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