Review – Bontrager Adventure Top Tube Bag (“gas tank”)

I Like Gas Tanks

Or Do I?

The Bontrager Adventure Top Tube Bag, or “gas tank,” is great. Is it great for every single person? Purt near! So thank you to GRAVELBIKE.com for facilitating this review, because I was very happy to check out another version of this type of bag. I was especially pleased to see that it sports reinforced openings and screws for securely attaching to your top tube, if your top tube has the capability, because my only complaint about gas tank bags is that they don’t stay in place.

Review, short version: Bontrager’s offering in this market is smallish and plain but highly functional with attention to detail (pockets! high-viz interior! reinforced zipper pull!), scores well on water-resistance, includes screws to bolt to the top tube (a necessity for some riders, including me) and a great deal at just under forty bucks. Interested in more detail? Read on….

Some riders won’t have this issue, but when I come off the seat to stand over the bike, I come forward enough to knock my crotch into any bag that sits atop a top tube, this one included. Wide Velcro straps are enough to keep the bag from falling off the frame, but I found it endlessly annoying to have to keep adjusting the thing back upright & retightening the straps. It’s annoying enough that I would not take either my previous top tube bag (the Revelate) or this one out on a race or any 50+ mile ride where time was a factor using only the Velcro straps. You know the riders most likely to keep running into their gas tanks? Bigger riders like me as well as riders with a shorter reach / shorter top tube to begin with.

I’m a big fan of feed bags. Feed bags, named for the bags of the same name that attach to a horse’s halter, are open bags about the size and shape of a big, closed-bottom coozie that attach around the head tube. Various brands have various features, but all do a great job of keeping snacks handy and accessible. Accessible snacks are critical on the kind of longer gravel races and rides I like, so I’m not looking to replace them, but I was also interested in a top tube bag that could keep smaller, loose items, like a lip balm or money, more secure. The Bontrager bag does this with a zipper protected by a rubber gasket that claims to keep items inside dry.

The Revelate version of the gas tank, with slightly more capacity, has instead of a zipper a fold-over top with an easy-fasten / easy-release catch. Note neither of these bags claim to be 100% waterproof. I wouldn’t cram a phone in either bag, even if it would fit.

I attached the Bontrager Adventure bag to the fat bike using just the two wide Velcro strips and first took it out on some very cold, very snowy rides in Colorado. I experienced the same issue I had with the Revelate bag – knocking it sideways every time I came off the saddle. Maybe in summer clothes I could make a conscious effort not to come so far forward, but eh, why do I want to use gear I have to think about? Like the Revelate, it never appeared at risk of detaching from the top tube, but it was annoying.

I found the zipper easy to use on the fly, even while wearing thin gloves. (I was using Pogies on the handlebars, so, no thick mitts needed. I tried it later wearing my big mittens and was unable to manage the zipper pull while riding.) The bag is roomy enough for keys, lip balm, and money/ID, along with a bandana and a few tissues. I could cram my phone in there – barely – but I didn’t think it was a great place for it. On a cold or wet or messy ride, I want the phone in a waterproof case designed to protect a phone.

I knew that my body hovering over the gas tank while riding wouldn’t give a true test of its ability to keep contents dry during precipitation, so I left it on the bike on the back rack to drive from Colorado Springs to Omaha. I stopped to check the bag after about 200 miles as snowy mountain sleet turned to rain in the plains. In the gas tank, I left a Kleenex and was interested to find that it was still dry when I stopped to check it. I was also interested in the zipper function in general and after road grit. I have a healthy skepticism of zippers!

Winter highway driving in Colorado, Kansas, and Nebraska provided plenty of salt and sand all over my Jeep, bike, and the Adventure bag. I have mild neuropathy in my fingers, so I was particularly pleased to find I could operate the zipper before and after coating it with road grime. Because I tend to torture my gear, I left the bag (sans bike) outside on my bumper overnight in the rain. That did it – the Kleenex was damp in the morning — but just damp, not soaked. Color me impressed.

Overall I prefer the flip-top opening on the Revelate bag to the zipper opening of the Bontrager, but I have to say, the Revelate did not do as well in my “Kleenex test,” and its inability to be attached any more securely means I pulled it off the bike and I’m not using it at all. I’ll be interested to see how the Bontrager bag fares after attaching it with the (included) screws to the top tube of my gravel bike and taking it out on a long ride. (Will update afterwards.)

Final thoughts today: as much as I was disinclined to like this small, plain, zippered bag, it kept surprising me with features & performance. In other words, like I said upfront – it’s pretty great, and if you’re not the type of rider who consistently bangs your crotch into top tube bags, you just might love it.