Revelate Designs has been in the bikepacking game since the very beginning. Founded in Anchorage back in 2007, Revelate has been making frame bags for a decade and has a wide array of products for every conceivable application. One of their newest bags is the Mag-Tank, a new take on the classic top tube bag.
What sets the Mag-Tank apart from similar offerings is the unique closure system. Specifically, it’s not a zippered closure, but rather a flap top with a magnetic buckle. But unlike some other magnetic systems, the buckle latches of its own accord, preventing it from popping open under impact. The magnet helps close the bag, and the design of the buckle keeps it closed.
The side panels are stiffened and reinforced to keep the bag’s shape.. The profile is a bit trimmed down from their other Gas Tank bag to prevent contact with the knees when pedaling. The top tube strap has a gripper built into it, to keep the bag from shifting.
The Mag-Tank measures 8.5″ long by a max of 5″ high, with a 2.5″ width at the stem. It tapers down to 2.5″ tall and 1.5″ wide along the top tube. Total weight is 4.5oz.
Out on the Trail
The crux of the Mag-Tank’s story is the ease of access to the contents within. Using a zippered top tube bag can sometimes be managed on the fly, but it’s generally quite difficult. Some bags might even require two hands to get the zipper closed. The Mag-Tank (Mag for short), on the other hand, is dead-simple: simply hook your index finger through the loop, pop the bag open, grab what you need, and slap it shut. The inclusion of the magnet in the latch means that you just need to get it close, and it will then be guided into place. But since the closure doesn’t solely depend on a magnetic seal, once the bag is latched, it’s securely fastened in place.
My first concern with the Mag-Tank was its ability to keep out moisture. With a flap top closure, this could be an issue. On their website, Revelate even notes specifically that “while the cover to this bag is designed to shed rain and spray, due to the large panel opening it is not a sealed bag or waterproof bag.”
However, I had no issues with water entering the bag. On muddy, rainy rides, all of the contents stayed dry. Even when hosing the bike down afterward and consequently, the bag, no water passed the flap top–impressive. I’m sure in a driving rain with the wrong angle the contents could get wet, but for a bag that’s not specifically sealed or marketed as waterproof, it does an incredible job.
The second worry I had going into this test was that items might fall out of the bag on bumpy trails. Fortunately this only happened one time. Just recently, on a heinously-rocky descent, a tiny multi-tool that I was carrying in the bag apparently worked its way out from under the flap and is now lying somewhere on Fooses Creek. You could go look for it, but I paid exactly $0 for that tool.
However, this is worth noting: while during standard bikepacking trips on gravel roads and relatively non-technical trails the flap top closure keeps the gear secure, if you’re planning to put a top tube bag on your enduro bike for gnarly, rocky descents, I’d recommend a zippered closure.
Finally, I ran into one issue that I didn’t expect: the Mag-Tank never sat quite straight on my top tube, regardless of the bike that I used it on. Even when I would pull the strap down tight, locking the rubber gripper in place, over the course of the ride the bag will lean to one side or the other. It’s always securely attached and won’t fall off, yet it doesn’t seem to want to stay centered on the top tub–even on square-tubed bikes like the one pictured.
I chalk this issue up to the straps used to hold it in place–namely, one major strap at the rear of the bag, and one small strap around the stem spacers. Oveja Negra’s Snack Pack, on the other hand, features a second strap in the middle of the bag for added support. There is no option to add such a strap to the Mag-Tank.
The Mag-Tank wins in ease of access, which is the primary function that Revelate Designs was trying to achieve with this bag. If you want maximum security of gear and imperviousness to the elements, they already offer their classic Gas Tank bag for such a use. Indeed, the Gas Tank is so ubiquitous that many people now refer to all top tube bags as gas tank bags, the way “Kleenex” now refers to any tissue you use to blow your nose with.
However, the tendency of the Mag-Tank to flop to one side or the other got quite annoying toward the end of my test. I’ve since switched back to a Snack Pack for everyday riding.
Thanks to Revelate Designs for providing the Mag-Tank for review.