<===The BD 2 after about eight months of constant use
I have had this very early production version of the Ergon BD 2 back pack since last summer and I have been thrashing it ever since. It's seen daily commuting use, mountain biking, long rides, and it's been in Nevada and Texas deserts. Rain, snow, and wind have not been strangers either. Here's an update on how it has been performing so far.
The BD 2 is the larger of Ergon's bicycle oriented back packs. It can hold a 100 oz. bladder with ease and a bunch of your gear as well. I have had it loaded down with upwards of 30lbs of stuff before and it rides great with even that much weight on board.
Generally though, it's just a full load of water, some nutrition, a few tools, spare tube, CO2 inflater, hand pump, shock pump, and maybe a few other sundry items. I always have room to spare. I'm quite confident that given the right equipment and a bit more organization, I could find room for some outerwear and more stuff necessary for multi-day epics. I have on a couple occaisions carried the full 100 oz of water with three extra water bottles! Anyway, the point is, you can carry a whole lotta stuff in a BD 2 if you need/want to.
<====My solution to a small problem
I have had great experiences with the BD 2 so far, but I have also experienced a couple noteworthy exceptions. One is the chest strap. It attaches on either side of each shoulder strap in front by a means of a plastic clip that is crimped on the edges of the shoulder straps. One of these popped loose at Interbike's Outdoor Demo last fall. While I was able to have it quickly and expertly repaired at Ergon's booth at the demo, an in the field failure would necessitate some other solution. Well, that's exactly what ended up happening to me later that fall. I simply looped around the shoulder straps webbing with the loose end of the chest strap. Voila'! No more worries since then.
<===It hasn't been a problem.........yet!
Another glitch with some early iterations of the BD series packs was a Flink bolt that backs out and separates the pack from the framework that straps to your upper body. See that shiny bolt head in the pic at the left? That's the guy! I have a replacement bolt that cures the problem, but I haven't installed mine yet. (I know, I know......bad boy!) However; I haven't needed to. I have it in the backpack waiting on the day when I finally break down, ( or the back pack breaks down!) and install the thing. I suppose I ought to do it, but I have only had to tighten the bolt twice and I am aware that it backs out, so I check it regularly. Anyway, the point is that if you already have an Ergon BD series pack and it was an early version, you can get a free replacement bolt from Ergon by contacting them.
Overall my impression is that the Ergon BD 2 is a great back pack/hydration system (You have to supply your own bladder) that can carry almost anything reasonably needed for serious rides to epic adventures. It is reasonably durable, well thought out, and beyond some quirky pockets and the chest strap issue, it has been flawless for me. I would highly recommend it based solely on how it rides with a load on it. The fact that it performs well above and beyond that fact is a bonus. If you don't need all that room, the BD 1 is also basically the same pack with a smaller carrying volume.
For those of you looking for something even more extreme/waterproof, the new BC 3 is coming soon. I've seen early versions of this pack and it looks killer! Commuters or serious multi-day riders need to check this baby out.