The Alpkit Gravitas jacket is an ultralight waterproof with a minimalist build, perfect for fast moving outdoor sports. It certainly managed to deliver the goods out on the bike.
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Built from a waterproof, windproof and breathable three-layer fabric made from two layers of ultrafine 7 denier nylon yarns sandwiching a super thin PU layer, it's featherweight and feels barely there when you put it on. I had some slight concerns of how robust it would be - its certainly not going to survive a crash on hard ground, but then not much does. The nylon is a ripstop style fabric, so the snags from bramble and branches have caused minimal damage. It's also internally taped to ensure water proofing.
The fit is close, but not restrictive. There's plenty of space to move around and the cut is definitely more athletic than baggy, which is appropriate for keeping the weight down and minimises areas of folding where water could pool. The rear of the jacket is cut lower and you can tailor fit using the drawcord. I’d have liked a little more tail drop, to really get a better coverage, but it's a minor gripe.
The arms are a good length with some well thought out cuffs that are elasticated by the wrist and have a slight bias cut that keeps an overlap onto gloves which is really handy for eliminating exposed wrists. The elasticated part allows you to push the sleeves back to ventilate if need be. The all-over fit is quite close as mentioned, so if the jacket is being considered as a winter jacket, I’d size up to allow more layers under it. I rode with a couple of base layers and a medium weight jersey which fitted fine, but a bulkier fleece may present issues with space.
There is a good size hood that has an effective peak that does work under a helmet, but I struggled to get it over the top of one. It is built in, and despite that, it didn’t seem to billow up too much, and when it did, it could be tucked down effectively with a drawcord that can close the neck down to keep it snug. The hood is semi-elasticated so can be pulled up with the chest zip done up.
There is a good sized chest pocket with stealth zip - things do tend to bounce around in it if they are heavier, so multitool or phones I found best stowed elsewhere, but perfect for a map, gels and lighter things. The zips both have useful pull cords to make it easier to do up or undo with gloves on. The jacket is built from as few parts as possible, which means fewer seams that can be potential weak points and there is also no visible stitching, which again reduces wear points and snagging. The main zip didn’t fail in heavy use, which can be a weakness of some jackets. The whole jacket is well finished and there where no loose threads or off taping on the seams.
The whole feel of the jacket is minimal but without anything missing. If you are out all day, and the weather is going to wet, or looks like it could be wet, this jacket delivers all the protection you could ask for. It's not got the weight or insulation of others, but its core function is lightweight weather protection, which it has in spades. The bonus of it packing down to a fist size pack is handy if you just want to have it carried for the just in case moments.
Out on the trail, I liked the fit and the excellent function - whilst not purely bike focussed, its cut well enough to perform admirably. It could use some venting or even some front pockets, but this would detract from its minimalist approach, and perhaps compromise its performance. In several heavy rainstorms, the water beaded and rolled off initially and over time the beading reduced with a degree of wetting out, but this never became a leak, but of course, with re-proofing and good care, it’ll serve well over a long time. It almost goes without saying that the light weight of the jacket makes it less likely to take repeated scuffs.
I was impressed with the level of breathability, obviously helped by the thin fabric. It also is properly waterproof - I spent three hours in heavy rain checking this fact out. The seams held up and the only place water found a way in was through the neck, as it crept down from my head. In a range of temperatures, its kept this breathability, and it has been fine up to around 12 degrees, which is about as warm as it got while raining in the test period. With a pack on, there was a degree of sweaty back, but nothing to get upset about, and it soon dried out.
