In my opinion, a cycling-specific backpack would need to be:

- waterproof, but not using a rolltop, because rolltops are annoying to get into, but possibly a large enough flap to protect the contents, in addition to weather resistant zippers
- airflow channel on the back, similar to the CamelBak designs
- able to hold/strap on the helmet when off the bike
- reflective elements
- loops to attach rear light

Ever ridden with something like a Timbuk2 messenger bag? Not bad at all. I started carrying home unbagged groceries in them long before it was “green” to do so.

I use my handlebar bag as a grocery container, my new Ortleibs have a handle and a shoulder strap also.

My favorite backpack has a plastic internal frame and a mesh piece that sits on my back giving it ventilation, it’s a great backpack but I’m not sure I’d ride with it.

Take an Ortlieb for larger loads. The handle and shoulder strap are very useful. But if I am doing my short commute with just my lock and a few other things (I keep clothes in the office.) and not picking up much on the way home, the messenger bag is fine.

Yes, I’ve had one since the ‘90s. Not bad, no, but bigger than I need usually, and they got waaay too trendy there for a minute.

I find myself using this bag a lot, just to carry a spare tube, pump, & repair kit, + phone or wallet or whatever other little things. It sits high on your back, but doesn't interfere with your helmet. It's important not to want to overload it, the fact it's small is part of the appeal.

Assos Spider Bag

https://cimg2.ibsrv.net/gimg/bikefor...ff45830f24.jpg

the back pack design the OP asked would lead me to believe that it has the purpose of clicking into the rack when riding, & then when you are walking to the remaining location or if you're hiking particle of the way, you sling the backpack on & walk on.

ugh, too narrow, never would use that.

Hey, I’ve never seen that and it’s kind of neat! Looks like it’s just stretch straps, non-adjustable; is it comfy?

Huh? How did you get lead there?!

Yes, the straps are stretchy, wide and flat; if you don't overload the bag, you don't even feel it on yourself - I think that's because of the placement higher up on the back.

Another nice side-effect of this is the bag doesn't interfere with the rear pockets of a cycling jersey, and you can still get stuff in and out of jersey pockets while wearing it.

OP; what's your background? Bag company trying to branch out? Cycling company trying to branch out?

I think you really need to start with a problem and try to solve that. Ideally something you have experience of already. What are all the other bag manufacturers missing that you can fix?

I picked up a similar sized backpack for running and it seems ideal for cycling too. If travellng by car and then riding then I don't want to have to muck about with re-fitting frame bags or whatever so I'm going back to the idea of a backpack for those trips.

The concern I have is back damage if I fall off; what'll I do if I fall onto my bag of tools? That's going to hurt.

Well... having a crash is gonna hurt no matter what. It would be different if 1) the backpack were massive, and 2) you were crashing at motorcycle speeds. Neither of these things are true in this case.

As these items are in the center of your back, and the brunt of a crash is going to be your arms, shoulders, and hips, I consider it a non-issue. Also, normally I'd have these items in my jersey pockets, so it's of little difference.

if the backpack was sized appropriately, a mypillow could help snooze a fall. Don't use a memory foam pillow as it might inflict pain from the last crash.

If I'm out on a long road ride, I do not want anything on my back that doesn't fit in my jersey pockets. For all-day long rides where I need to carry more stuff, the Ortlieb seat pack works for me: waterproof, light, expandable and compressable to carry varying volume of stuff.

I don't do a lot of trail riding, but the small Camelbak I have is more than enough to carry water, phone, snacks.

Commuting is where it gets interesting. I have a sufficiently long commute that makes me vastly prefer riding my nice, CF road bike that has no rack mounts. I shuttle clothes on days where I don't ride in, but occasionally use a Kelty sling bag to take stuff. The biggest downside is that there's no good way to take a laptop without resorting to a full-sized backpack. I'm lucky enough to have a second work laptop, so I just leave one at home at all times. But figuring out how to transport a laptop is a regular issue, in fact in the last month I've seen 2 threads where posters are trying to figure out the best way to take their laptop, with a traditional backpack being the last resort due to the lack of desire to weigh one's upper body down and reduce ventilation on hot days. Oh, I've also used a messenger bag before but agree with Bike Snob NYC that those are designed for the opposite task of being able to quickly exchange stuff, not to stay out of the way and in place on a long ride.

For me if it's for "cycling" it should be aero, hi visibility and reflective at night or might as well just use the other 100 back packs that I already own.

> see TRASH backpacks

Is it big enough to stuff bike pants and jacket in?

If they are thin shells, then yeah, shouldn't be a problem - but you wouldn't be having a lot of space for much else.

The only problem is finding one, I got mine locally, and I haven't seen any around.

Water resistant/waterproof and easily accessible pockets for me.

I dislike backpacks for the following reasons:
- it raises the center of gravity
- on hot days it makes you even hotter
- it makes a wet spot on your back during and after you take it off
- putting it on again on a sweaty jersey is like putting on a wet bathing suit.

Instead for hiking I use a Moutainsmith fanny pack. Sure you still perspire against it but its a smaller area and it keeps the center of gravity lower. I also have from a Seattle to Portland ride a fanny pack as swag that has two side holders for water bottles which I also use for hiking. It was made for cycling and is great, but a bit small, the MtnSmith is much larger and I added water bottle bag/holders. Good luck