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Long-term Review: Thule’s Chasm Water-Resistant Duffel Taken to the Races & into the Air

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Just over a year ago I was looking to replace a worn out gear bag to haul around all of the cycling kit, helmets, and shoes that get thrashed and muddied each weekend racing cyclocross, and I happened across the water resistant duffels from rack-maker Thule. The Chasm bag offered a big opening to make loading and unpacking easy, flexibility of how to carry it, and five different size options from 27-130 liters. I opted for a bright Zinnia yellow bag in the middle Medium size, and have stuffed it and drug it through a season of cross racing, then packed it back up as both checked and carry-on luggage for spring and summer air travels. In that time, I’ve also needed to steal it back from my wife on a number of occasions, as its flexibility and hauling capacity has made it a go-to in our household for pretty much any weekend travel. Get the full details and see how it has fared after the break…

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All of the different sized Chasm duffels use the same construction, pocket and opening layouts, and tech features. One of the most useful features we’ve liked is the removable shoulder straps that convert it from a duffel bag to a backpack. The straps have little metal hooks that just connect into sewn-in loops at the top and bottom of the bag. Then the normal duffel straps can get folded down to the side and snapped down to stay out of the way.

While this is one of our favorite features (making it easy to haul a lot of gear and carry a bike at the same time), it is also the cause of our biggest gripe with the bag. Those little metal hooks seem so secure when we loop them on, but more than one of us (and on a few occasions) has thrown a heavy, loaded bag over one shoulder only to have the shoulder strap pop off and swing away from us. The problem has never occurred when we were carrying the pack, only when first shouldering it, so it is predictable enough that we’ve learned to pick the bag up gingerly and avoid it, but it is quite frustrating.

We would really like to see this issue resolved, because the removable shoulder straps are incredibly convenient. Anytime we have the bag packed full and need to carry it any sizable distance, it goes on our backs. But when traveling by plane or just going short distances, it is really nice to do away with the extra straps swinging around. I’d personally be happy with it just being a bit more difficult to mount and remove the straps. Now it is just that the ease of installation sacrifices a bit of security.

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Our medium sized Chasm is about 32 x 40 x 70cm (12.5 x 16 x 27.5″) when it is packed and fully expanded. Thule rates its carrying capacity at 70 liters. That’s a good bit too big for using as a carry-on with most airlines, but out of curiosity I was able to use the bags compression straps to get it down to about 22 x 40cm in section and folded the end in enough to get it on the plane with me on more than one occasion to speed up arrival at my destination.

The bag is made of a 1000 denier nylon fabric with a fully waterproof TPE tarpaulin coating, that Thule advertises as phthalate-free. It is available five colors – mist gray, cobalt blue, dark shadow gray, aqua green, and zinnia yellow – each with a black base and straps. The bottom of the bag adds an additional layer of nylon and a thin pad to improve durability and water-resistance. The duffel’s main two zipper pulls include loops for a small lock to be added, and there is a single small outside pocket with a waterproof zipper for packing small items.


Overall the waterproof tarp-like fabric of the Chasm has been very durable and withstood serious abuse. The worst the bag has seen was probably from baggage handling, and even then after more than a year and three flights in the hold, there are just two spots on the bag where any visual damage to the fabric can be seen. The first above the E in THULE above, has a small scrape in the outer black TPE coating, but didn’t make it through the nylon underneath, and the inside has a second un affected TPE layer maintaining full waterproofness. The second and similar scrape in the yellow fabric on the top left of above (along one of the light colored folds in the photo) is even smaller and also does not make it through the underlying nylon. Other than that the only noticeable wear besides some dirty smudges is a very minor fraying on the nylon on the unfinished edge along the outside stash pocket opening.

While the fabric is rather durable, the construction of the bag is simple enough and the fabric flexible enough, that the duffel still folds easily  to store it when not in use. All of the external straps, buckles, snaps, and zipper pulls have survived for the year of regular use with no noticeable wear of any sort.

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The large, oversized mouth of the Chasm opens up like a clamshell to make it easy to load and to retrieve anything packed inside. If we think of the duffel like a rectangular box, the opening is just smaller than the one full side with a small amount of wrap over onto one end. This helps the bag retain its shape when it is fully open, allowing it to wrap or hold its contents, but also provides a bit of top loading access when it is used more like a backpack. The pair of opposing zipper pulls also makes it easy to slide them around to any point on the duffel to access your gear inside, without letting everything spill out. Lastly 3 internal mesh pockets (1 full length on the top, one small over the full length, and a flap pocket along the hinge of the bag’s top) and a removable mesh stuff sack help organize your gear and make smaller items easier to keep track of.

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To reiterate, the Chasm duffel bag has served us well for all kinds of cycling trips, and most usefully has made it easy to pack and haul all of the gear we could imagine to use for either a weekend of cross racing (triplicate of everything from head to toes) or a weekend mountain biking trip. The Chasm has kept our gear dry in the rain, kept our car clean when it was hauling wet & muddy cross kit, and flown across Europe with me to test the next best bikes from London and across the Alps. Besides the fact that I would love to see the removable shoulder straps get a bit more secure, the only thing I can really think about it is that I might want the 40l Small version as it will be more trouble-free as an airline carry-on. That said, I’m not thinking of letting go of this Medium one anytime soon, and even with the great Scicon Rainbag that is great for a day’s riding, this duffel makes sure to keep me well stocked for any adventure.


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Steve Ahrens
7 years ago

I did my straps like yours, then I saw this: https://www.youtube.com/watch?v=wi3VyumRxSY

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