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Ask A Gear Guru: Do I Need a Bento Box?

Bento boxes are an efficient way to carry fuel—some may even have aerodynamic benefits. We take a look at four great options.

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Pure cyclists are known to scoff at bento boxes, and we can’t always blame them—some triathletes load theirs up like they’re preparing for war. But jersey pockets can only hold so much and the longer the ride, the more important the calories. Bento boxes are a convenient way to carry lots of fuel on long rides or to access nutrition during races without completely disrupting your bike position.

Contrary to popular belief, adding a bento box to your frame will not hurt your aerodynamics, said Mark Cote, the aerodynamics and triathlon product marketing manager at Specialized. “If you have a stem and spacers sticking up off your bike, there’s already a lot of drag that comes from that recirculation area,” Cote said. “The nutrition kind of hides in the wake of your stem.”

If you’ve ever been to an Ironman event, you’ve probably seen athletes with 15 gels taped to their top tube, which “messes up your aero like crazy,” Cote said. “The bike should be as smooth and as perfect as possible. Personally, I would race with a good bento on a frame where it makes sense or with gels in my pockets and that’s it. I try to keep everything off the bike as much as possible.”

The good news for triathletes is that bento boxes are also having a renaissance as gravel riders have adopted them as de rigueur for off-road riding. This means you can find more types of bento boxes, in bigger sizes (if you prefer) than ever before. And as such, more and more brands are equipping their road and tri bikes’ top tubes with braze-on bolts—something almost entirely unheard of just 10 years ago. If your road or tri bike has braze-on bolts on its top tube, you’re free to use any bento boxes with integrated attachment—meaning you can forego the velcro straps and achieve a cleaner setup by bolting the box directly on.

Companies such as Dark Speed Works (mentioned below) have improved the bento box design by creating more aero-shaped options that form sort of a “tail” instead of a box shape, which essentially just moves the drag area farther back. Additionally, many of today’s tri bikes like Cervelo’s P-Series and PX-Series or Quintana Roo’s PRsix2 Disc come with aerodynamically optimized bento boxes built in. Mimicking these pre-installed nutrition options, Cote says to make sure your DIY bento is tucked up next to the stem for the most aero benefit.

We recommend the following four bento boxes:

Profile Design Aero E-Pack


Profile Design offers multiple sizes of no-frills E-Packs. Attaches to the top tube with Velcro straps. Profile also has updated versions of their basic bento, like the ATTK S ($49), or if you have braze-on bolts already on your top tube, the super-sleek ATTK IC ($34).

FlowCell FuelCell


Flowcell Bento Box

Though it’s one of the more pricier options on the list, the FuelCell is certainly one of the more innovative. The box itself can be attached either via velcro straps or bolted on directly (if you have braze-on bolts installed in your top tube), and it boasts a ton of space—enough for four 66g gels. The big sell on the FuelCell is that it uses a clever sliding door to secure and access whatever nutrition products you keep inside. One note: Unlike some bento boxes, it does not provide an option to store Di2 junction boxes.

Dark Speed Works 483 Bento Box


DarkSpeed Bento Box

Dark Speed Works has made a splash in the aero-savvy tri community with its sleek, low-profile design. In addition to the Speedpack 483 that fits nearly all tri bikes regardless of stem arrangement, the company created specialty boxes that integrate into the frames of high-end “superbikes” such as the Trek Speed Concept and Cervélo P5. The 483 zips from both sides so you can access what you need without things flying out, and the skinny tail area is the perfect place for CO2 cartridges. They’ve also released a larger version called the 683 ($53) that holds even more.

Xlab Stealth Pocket 400c Bento Box


Though most well known for their front and rear hydration systems, XLab also produces a wide line of top-tube bento boxes. With offerings that range from 100c (approximately one bar and three gels) to the massive Stealth Pocket 400XP (that stores up to six gels with external pockets). Our choice is the basic Stealth Pocket 400c that still offers universal top tube straps—the 500c version is larger, but requires top tube braze ons—and stores up to six gels while protecting against electrolytes and sweat as you ride.

RELATED: The Best Triathlon Bikes, Updated for 2022