Though not cycling specific, I’ve been using a Boreas pack- the ultralight Topaz, for a little while now for day trips with the pack raft. At 25L, it’s large enough for me to throw the raft and paddles in. I can go on a day trip on the bike or on foot- and weighing in under 14 oz., I hardly know it’s there. One downside is that I’m limited by only packing stuff in there that can get wet, as it has no waterproofing whatsoever. Enter the Waterproof Series.
The Echo $139.99 is a 25L pack and The Monterey $164.99 is the larger, 35L version. They are designed to allow “adventurers to push the envelope and go to new locations.” Both sport 210 denier nylon ripstop with a thermoplastic polyurethane (TPU) coating. The roll top waterproof skirt keeps your gear dry, and there are draining side pockets for wet gear. The molded EVA foam and tuckable suspension allows for a comfortable carry. Both are available in Canyon blue & Lava Black.
Boreas is based in San Francisco (though the packs are made overseas) and has been around since 2010. They build lightweight, clean designs and the founder, Tae Kim was raised in Alaska before he left to pursue a career in design (eventually working as the design director for The North Face before starting Boreas.) I’m so far impressed with the blend of light weight materials and quality construction that I’ve seen in their products. I have carried my bike and raft all together, strapped haphazardly to the Topaz when a bike/raft trip brought me through some nasty rapids I had to portage around. All the while I was expecting something to break loose but it held on fine.