I’ve used four assorted top tube bags on many of my bikes. This bag is by far the largest one, and I’ll say the best! Why? I think Blackburn created this bag with everything I wanted. It comes with two of those wide straps on the top tube, and the narrower strap for the head tube. The bottom straps have three placement slots, allowing great flexibility in mounting, and if these straps aren’t long enough for the frame design, you can add any strap that will fit the slot, (I had to do that on my mountain bike frame). The typical road bike ride doesn’t require the security as mtbing needs, I use two top tube straps on the mtb. https://www.blackburndesign.com/bags/outpost-bag-collection/outpost-top-tube-bag.html
From the top view, you can see the width of this bag, it is much wider than the minimalist bags I’ve used, those were about the width of this top tube. Even with this extra size, my knees do not hit the bag. One oddity of top tube bags is how they sit on the tube. Notice that hydraulic brake line that is off to one side. This bag requires occasional re-centering. This can be reduced by using two straps, and a good tug on each.
The mesh pocket is a great place for quick grab items, or on mine, you’ll see my SPOT GEN3, https://www.findmespot.com/en/ , I’ll cover that device soon. I chose this bag based on the measurement of that mesh pocket, thought the SPOT would fit and would get enough “sky exposure” in that position. It was snug the first time I pushed it through the opening, but after many times, it slides in easily and is still secure.
This is a 12 ounce RedBull (https://energydrink-us.redbull.com/en) in the bag, fits easily with room left over. Road rides often need a little boost at store stops, and I sometimes grab an extra RedBull for the road. I usually fill the bag with ride food, or a special tool, or other items as needed. There are two zipper pulls and both are easy to slide, even around the corners, although you may need to support the bag a bit while doing this. I usually don’t take the rear zipper all the way around the front, this allows easy one handed opening and closing. It’s not insulated, but a cold drink will stay near the desired temperature for a little while, better than a jersey pocket! The red color is good for visibility of assorted items within the bag. A nicely designed velcro divider comes with the bag, I’ve never used it, mostly because it slightly limits the type or size of items.
There are two outside slots, the left one is zippered, and this right one is not secured, but it holds an ID card nicely! I need one to get to the office, and at first I worried it would bounce out and be lost, leaving me trying to explain to security where I lost it and begging to let me get to work. Of course that only happens during really cold rides or pouring rain!
I was curious how waterproof the bag would be. I’ve ridden in a few soaking rains, and some water did get in, but not enough to collect or fill like an open dish. It did dry quickly with the lid left open. If you need to load it with a non-water resistant phone, or similar item, just wrap that device in a plastic grocery bag, or zip lock bag.
Would I buy another one of these bags? I’ve been abusing this bag for over two years, (purchased in August 2016) and no aspect has failed. The mesh pocket always spreads open and holds onto whatever I insert. I’ve overloaded the main compartment and the zipper always closes. Retail price is $49.95, and I did buy another one! I grew tired of moving it between my two bikes, so I bought a second one just to solve that issue. The headset stack on the mtb is shorter and that front strap on the bag has a lower slot that I could move that strap down to, and it snugs up nicely to the steerer tube with that great design feature.