- Color: Multi
- Size: 36 x 25 x 21.5~29 cm
- Brand: Topeak
- Material: 600 Denier Polyester
- Vehicle Service Type: Bicycle
- 600 Denier Polyester
- Made in the USA or Imported
- Expandable bike bag with divided main compartment and expandable top
- 2 side panels with expandable panniers add even more storage space
- 600-denier polyester construction with rigid molded side panels
- Shoulder strap for easy carrying; RedLite clip and elastic top bungees
- 1,380 cubic inches of storage; measures 14.5 x 8.5 x 9.8 inches (W x H x D)
- 1 Divided Main with Multi-stage, Expandable Top, Two Side with Expandable Panniers
- 1160 g / 2.53 lbs
- 20.2 l / Capacity 1380ci
- 420 Denier Nylon
- Water Bottle Holder, ο»ΏShoulder Strap, ο»ΏCarrying Handle, ο»Ώ3M Reflective Strip, ο»ΏRedLite Clip, ο»ΏElastic Top Bungees



















Asher Taylor-Dawson –
Update #2:My “Junk-in-the-Trunk Bag” is still going strong, and I’ve discovered a perfect upgrade for it:Β JL Childress Tall TwoCOOL 2 Bottle Cooler, Black The TwoCOOL bottle cooler is an ideal fit and allows you to carry a chilled lunch even on hot days. Together, they make an unstoppable Bicycle Fueltank!Update:I’ve now been using Topeak’s MTX Trunk Bag (AKA the “Junk-in-the-Trunk Bag”) for a good six months. Not a single day has gone by that I haven’t been glad I bought the thing. I also purchased the rain cover that Topeak sells to go with it, which is also great. Depending on what I’m doing on the bike, the MTX Trunk bag carries anything from a few tools and some snacks to a full-on one- to two-man picnic. It also still looks great so far.******After a long internal debate between this product and a less-expensive insulated bag made by Avenir, I decided to spring for Topeak’s MTX Trunk Bag EX. I had already purchased a compatible rack, and I wanted to see if the MTX quick-connect system lived up to its promises.In short, it does.The plastic track on the bottom of the back slides into a channel on the rack (which does not, I should add, prevent using the rack with non-MTX trunk bags and other products) and the little yellow clip secures it. The whole process takes a couple of seconds, but once attached, the bag is extremely stable. I feel perfectly comfortable leaving it on and loading the bike on the front of a bus that travels part of its route at interstate highway speeds.Removing the bag from the rack is also a snap, which makes taking it into the commons at school during lunch time easy (the included shoulder strap comes in handy here, too). There’s no fumbling with velcro or clips; just press the little yellow plunger and – presto! – off she slides.Meanwhile, the bag itself is thoughtfully designed. On the outside, you’ll find two zipper pulls, a loop at each end to which you may attach the included shoulder strap, two small mesh pockets running the length of the bag (turns out these are handy for carrying small things — lip balm, a lighter (just in case!), stuff like that — or even a couple of gels), a very tight loop for a taillight (this is good; the tightness of the loop prevents the taillight from bouncing loose when you hit a pothole), and – on the lid – another mesh pocket with a bungee.I suspect this last bit is intended as a holding spot for the bag’s optional rain cover, a rolled-up windvest, or rain jacket, but it could just as easily hold a small picnic blanket, a baguette, or an extra pair of gloves. As other viewers have observed, it’s a bit loose for smartphones or small multitools. (Update: I’ve now had gloves, jackets, hats, arm-warmers, groceries, and all kinds of things crammed into the pocket and/or the bungee — what a nice touch!)A reflective strip running the entire length of the bag on each side offers a visibility boost in a spot (just over the rear wheel) where such a thing might come in handy, an exceptionally thoughtful touch of the kind I’m coming to expect from Topeak.Inside, the bag continues to reflect the touch of a thoughtful designer. A divider, attached with hook-and-loop fasteners, can be used to carve up the interior as desired — or you can just pop it out and, if you’re so inclined, stick to the bottom of the bag flat, so it won’t get lost. Thus far, I’ve left mine in place, since the interior comes nicely divided to store a sandwich box or two in one compartment while various sandwich-related accessories (including a full 16-oz bottle of horseradish sauce!) occupy the other.A pocket on the inside of the lid can hold inner tubes, an ice brick, or other such things (it’s also great for stashing anything small that you want to be able to find quickly, such as gels, keys, or an asthma inhaler).In terms of capacity, the bag is more than large enough to hold lunch and a snack. It would make a great self-supported century or brevet bag (update: in fact, it’s way more bag than you need for a 100k populaire!), offering enough room to store both copious snacks and plenty of tools and spare parts. I also plan to use it on multi-night bike tours to store food (I have found that, for me, a loaf of Brownberry’s double-protein bread, some peanut butter, some jelly, and some creme-filled wafer cookies tend to do nicely). Being able to easily slip it off the bike and carry it to the table (or hang it high and away from the bike and tents in bear country) is a very strong point in its favor.Of note: as an option for storing cold stuff on warmer days, you’ll want to add some insulation — a small insulated sack with an ice brick or a small vacuum jar should do the trick. You could even feasibly keep a hot insulated jar in one end and a cold one in the other. The foam in the lid may add some element of insulation; the sides seem to primarily just add shape.–Summary–If you plan on commuting or camping by bike, riding self-supported centuries, or randonneuring and you’re in the market for a good rack and trunk bag at a comfortable price point, I highly recommend Topeak’s MTX Trunk Bag EX. Coupled with Topeak’s light, robust Super Tourist MTX rack (found here: http://www.amazon.com/gp/product/B000ZKHN6Y/), it’s a sterling combination.
Aaron R. –
Time owned: 100 milesThis bag is pretty slick when used in conjunction with one of Topeak’s racks (I have the Explorer). Just slide the thing on and go. Packing for my commute has never been easier. Without the rack, however… you can probably find better. Yes, the quick mount option makes that big of a difference. It sounds relatively minor, but then you use it and find that it turns a decent bag into a great bag.I’m 5’9 and 195 lbs (so probably wear the same sizes as many of you reading this). The trunk bag itself is large enough to fit a pair of pants and a shirt without expanding the top, but it wouldn’t really accommodate my shoes, even with the top expanded. The expandable top is diagonal (which makes sense, as the trunk bag nestles right underneath the back edge of my seat), so it’s not a full 2″ of additional space. Still, it’s a nice option to have if you have something that’ll ALMOST fit… or you happen to be much larger than I am and need the space for your clothing. The trunk bag itself is, additionally, sectioned off using a small divider. I pushed it off to one side, since it only served to make things more difficult for my particular usage. It’s nice that it’s optional, otherwise the trunk bag would be useless to me as subdividing the compartment makes two spaces that are too small for me to utilize.The expandable panniers are awesome… conditionally. One pannier is roomy enough to fit my size 12 shoes with a bit of room to spare. They sit relatively high, but it doesn’t really bother me (and heel strike is a complete non-issue). If you prefer your panniers to have a lower center of gravity, they could prove problematic (or at least take some getting used to). The material, however, leaves something to be desired. The rigid panel on the back is solidly constructed, and feels like it’ll hold up (while serving the function of keeping your panniers out of your spokes). The front and sides of the pannier, however, feel flimsy at best. If you have anything with sharp edges in your panniers (poles/pipes, knives, an erector set… anything with an edge), don’t be terribly surprised if you find it poking out a bit. On the plus side, they also give the appearance of being incredibly easy to patch (if you can count that as a plus side). If you’re utilizing the panniers to carry larger items that don’t necessarily weigh a lot or have sharp edges, the ability to zip them out and have the extra space is amazing. If the panniers happen to be made deceptively strong, great (though I doubt it). If, however, you’re looking for something to carry a lot of heavy gear… make sure to carry duct tape or something to make a patch. Better safe than sorry. The side pouches that contain the panniers can also be used to store small miscellaneous items, but not much (I use one to store the shoulder strap and the rain pouch, and I had to be particularly careful not to snag the rain cover in the zipper… so there’s not a lot of room). The bottom of the panniers have a weird bungee thing that I use to “secure” the bottom of the pannier to the bike (no idea if that what it’s for or not… if it IS, it’s pretty poor design since it’s a small loop). It’s a bungee, so it doesn’t really do much to stop the pannier from bouncing around (not actually a problem with or without the bungee with my set-up) and as I mentioned earlier, it’s a loop with a cord stop that allows you make the loop larger/smaller. I feel the need to secure it around something, lest it get caught in something nasty, but it doesn’t really do much.The bungee on top is a nice addition, but I don’t really use it. It bungees, as one would expect. The mesh pouch, however, is much more useful. I have a Galaxy Note 3 that I sometimes put in this pouch. It’s not the most secure place in the world to stash my phone, but it doesn’t fall out while riding. Something smaller would be held relatively securely (the Note 3 sticks out the top of of the pouch). The water bottle holder on the back holds my wipes. No digging around after my commute. Good stuff, that. There’s a mount for a rear light as well, but that’s something that I feel is done better by the light mount on the rack itself (it sits just below the bag). I instead use this as a place to clip a carbiner, when necessary (my keys, usually… not that there’s a shortage of places to clip them on the bag).The biggest hit against the bag is that it’s not waterproof. With the panniers up, the main trunk bag feels solidly water-resistant (as advertised)… but I wouldn’t trust it during a long ride while it’s pouring rain outside. A steady drizzle, or even light rain, and it’d probably be fine. The panniers are another story. They don’t seem water-resistant at all. If you plan on using the panniers, make sure to either get the rain cover, carry a garbage bag, or have a plan. It’s annoying that after spending a not insignificant sum of money on a bag that you’d then be expected to drop another 20 on a rain cover (or make do with your preferred cheaper method, whatever it may be)… but that’s how it is. I bought the bag through an Amazon Warehouse deal and just convinced myself that the rain cover was part of the bag cost.All in all, this is a solid and well-designed bag. If you have one of the Topeak QuickMount racks, get this bag and you won’t regret the purchase. If you have a different rack, however… shop around a bit. There is a plastic bit along the bottom of the bag (and a yellow tab in the front) that may or may not cause difficulty in mounting to a non-Topeak rack. There is, additionally, no other way to secure the bag to the rack itself (no loops or snaps or velcro or anything that you can put around the rack to hold it securely) other than the proprietary mounting system. I’m sure it’d work with a little bit of ingenuity, but why bother when there are other well-designed (arguably better designed) bags out there that would work so much better? The lack of versatility is a glaring potential problem if you have to deal with multiple racks.
KCO –
This bag w/panniers is pretty nice.My only comment is it rattles a bit when empty. Not a big deal, but you know that it hasn’t fallen off.I like how 95% of the time the panniers are zipped up (stowed) nicely.A nice feature to include in the next revision would be a locking feature.I am a very casual user (retired) so I use it to store a lock and rain coat when running errands. We’ll see how grocery runs turn out.
Paul Auman –
I received the product the product before it was expected to arrive in good condition.
Nelson V Diaz –
Great bag and the 2 side saddles add so much versatility. Slides right on and off and has a shoulder strap. Really well thought out. I was not able to keep a rear light straight using the loop on the back of the bag. I had to use the cup holder strap to keep the light pointing straight instead of down.