bigger than my mule – no bladder required tho

go for a dakine heli pro, has an insulated compartment for a bladder pretty sure its around 26L

One of the bigger Wingnuts. Comfortable even when loaded.

ive got a 2010 HAWG NV, black/grey, great condition, about to go up for sale minus the bladder.

I really love my Wingnut Adventure (26 litres). The way the weight rests on the hips thanks to the ‘Wing’ pockets really makes a big difference with a big (so probably heavy) bag.

http://www.roughrideguide.co.uk/Wingnut-Adventure-Rucksack.html

If you want silly big, look at the Camelbak military range, I’ve got Motherlode for multi-dayers or if I’m doing video or photos out in the wild. The base weight for the pack is quite heavy and if you max out the water capacity it’s difficult to get anywhere near it’s capacity before it’s simply too heavy to ride with. But I’m only little so you might be fine. And when I say maxing it out, I’m talking like most of your bivvy kit plus water would go in there!

Otherwise Dakine Apex is slightly bigger than a Mule but arguably more useful space. Pretty good pack for shorter trips too and it really packs down flat when empty.

Take a look at ski packs.
I shelled out on a Lowe Alpine Fall Line. It’s a ski pack really, but is brilliant for everything. It’s very comfy and very stable. The load straps mean it pinches up tight when part full, or they can hold clothing if you happen to go out over dressed.
I use it also for walking days out. Easy to remove back stiffener which allows it to bend (which is necessary) for cycling.

Osprey Talon – nice and light, 33L is a good size.
Vaude Alpin – had one for years, its 30L and bombproof.

How large is large? I’ve just bought one of these which is 20 – 25 litres. Not had it out on the bike yet, but the main things that attracted me to it were:

1. Big open pockets on the side for stuffing gear that doesn’t need to be zipped away
2. A dedicated map pocket (my old ‘sac was naff for carrying a map)
3. One of those back systems that sits slightly away from the back
4. Two largish internal compartments rather than lots of tiddly pockets, but still has some smaller pockets on the front
5. No hydration system (I have one already).

Made by VauDe for Edinburgh Cycle Co-Op. Some of VauDe’s other day packs look great for cycling too.

We use Deuter Futura 28

I have a Dakine Apex that has ‘swallowed’ everything I have ever tried to put in it with room to spare.

http://www.dakine.com/sport-packs/bike/apex/

How big? I am a big fan of berghaus – I have a freeflow 50 which I can put a weeks camping / trekking kit in or I have a arete 30 which is a big day pack and very secure as its a rock climbing pack. Both will take bladders if you need one

The freeflow sits away from your back to avoid sweaty backs – comes in a 35 as well IIRC

For what and how big? Any particular features needed?

Something Osprey would be my recommendation though.

EVOC Freeride Trail worth a look? That’s a big bag. 20% off with code “PACKITIN”

http://shop.18bikes.co.uk/products.php?plid=m17b0s459p0&tbv=_OTHER_Luggage

I’ve also got a Freeride Tour in the shop, even bigger – £140 down to £112.

http://www.evocsports.com/index.php/en/Freeride-Tour.html

Back protection as a bonus on these – removable for when you don’t want it/use separately without the bag.

If you don’t want to spend much wonga then Decathlon is always worth checking out – loads of choice and their stock keeps changing.

I’ve been very impressed with my Osprey Raptor 18L – fits lots in for an all day ride and clinches down when its not so full.

The main selling point for me is the bladder and bladder sleeve/holder. No matter how full the bag is, you can always easily slide a full bladder in…..very different from my Camelbak experiences.

Anyone use this?
CamelBak Octane