Topeak Fork Drybag 4L

The Topeak Fork Drybag 4L is light and very well made, with an air release valve for ease of compression and two Velcro straps to help with retention. For the price, it’s an excellent bit of kit.

Drybags are the go-to for most people needing to carry luggage off-road or on long adventurous trips. Unlike a pannier they will survive apocalyptic weather experiences up to and including complete immersion – hence the name. Drybags were invented for watersports, where weight isn’t that much of an issue – my first bags were made of very heavy PVC. The fact they are still going strong over 30 years later is testament to building strong – but if you’re looking for lighter ways to schlep up hills, or more pliability to compress down easily, you need a different material.

The Topeak Fork Drybag is made of TPU, a very light and tough material that’s rapidly becoming the standard for bikepacking gear. It’s also 100% recyclable and safe, with no nasty ‘forever chemicals’ in the mix. At 125g including buckles, for a 4L bag this is light.

The Fork Drybag has a circular base, meaning it stands up by itself when popped on a table. The seams are welded, and the overall feel of the bag is high quality..

Air release valve

It has two technical features that mark it out as optimised for bikepacking use. The first is the air release valve. A little smaller than a shoe Boa dial, the Air Release Valve lets you release all the remaining air from the bag, after you’ve stuffed it full and folded over the top to create the classic ‘drybag’ seal. Being able to release the last gasps of air once closed is a boon, to prevent the bag retaining air and then slowly deflating over the course of a ride. While a rolled-closed drybag is immersion proof – meaning if you get a dunking, no water is realistically getting inside (Topeak lists it as ‘weatherproof’ rather than ‘waterproof’) – it’s not airtight. Air molecules are technically known as ‘really, really small’, and over time they will work their way out of a closed drybag being compressed by the straps holding it in place on a bike.

This slowly-deflating scenario is undesirable, as what was a tightly-fitting and silent item of luggage gradually becomes looser and therefore rattlier. Noise is not conducive to a serene cycling experience, and any movement against the retaining straps or mount invites premature wear and failure of the bag’s structure, not to mention the risk of wear of your gear inside the bag. Think a pot rubbing against a jacket, or a tentpole rubbing against a flysheet. Unwanted movement is the enemy of your bike, luggage, mounts and stuff, and any feature that will minimise movement is therefore A Good Thing.

Vertical straps

The second feature of the Fork Drybag is the pair of chunky vertical Velcro straps that hold your horizontal compression straps in place. These mean the straps stay in the same place horizontally even if they loosen over time, thereby aiding in keeping the Fork Drybag where it should be. If your bag gets so loose that it’s relying on these Velcro straps for coherence, you really aren’t paying attention – but it’s good to have them nonetheless. I found the Velcro handy for holding my go-to Voile straps roughly in place while sorting things.

The max load rating for the Fork Drybag is 3kg, which is really quite a lot for a 4L bag – think putting 3L of water in there and strapping it to your bike. If you keep the inside relatively clean it makes for a good water carrier between yonder distant burn and your campsite (always advisable to boil or filter before consumption, obvs).

> How to go bikepacking: A beginner’s guide to getting started

Topeak has sized the Fork bag to work with its own VersaCages, but any type of cage or plate will do. You don’t actually need a bottom plate, if the bag is strapped down sufficiently and your straps are also retained so as not to slip.

Value

There are many options for drybags in this capacity, and some have air release valves – but I couldn’t find one with a valve that was made of trail-tough material, and also, critically, was of the longer and narrower shape that a fork-mounted bag requires to minimise the risk of catching on trailside projections.

The full price with the included features makes this good value – and looking around, they’re often considerably cheaper than list.

For more options, check out our guide to the best bikepacking bags. 

Conclusion

A few years ago I had some custom fork drybags made, because I couldn’t find ones long and narrow enough to suit. With the Fork Drybag 4L, Topeak has done an excellent job combining form, materials and features to create what I believe will become a classic bit of kit for backcountry travel.

Verdict

Excellent way to carry stuff on your fork – light and strong with well-executed features

All the deals displayed on our review pages are pulled from a constantly updating database feed of the best affiliate deals available. The criteria for deciding on what are the best deals is who is offering the lowest, delivered price. In most cases we will be showing the very best deal available online, but sometimes you may be able to find an item cheaper. If you can please feel free to post a link in the comments box below. To find out more about affiliate links on road.cc click here.