Recommend a robust & durable backpack

[pjclinch]

Karrimor making school bags?

Before they switched to a pannier each on their own bikes my kids used Karrimor daysacks as school bags. They were okay for the job, travelled in a pannier on the Me'n'U2 to get to school and back, and were cheap as chips. Absolutely no point in getting a ten year old a "bag for life" because their life may well take a different direction than you'd envisaged, they'd be entirely likely to lose it or stop using it because it's not cool enough etc.

Well the 30 litre product I was considering is compartmentalised like a school bag and actually what I’m wanting is a single compartment bag that doesn’t have large pockets - no pockets at all would be fine. A bag capacity of 25 litres is what I have now - seems enough - but 30 could be handy … but bigger bags than that can be unwieldy.

That's what compression straps are for. Not only keeping a load stable but shrinking the bag too. Climber's packs tend to have compression straps as standard, which adds a bit of weight and cost but makes a bag much more flexible. You can effectively use them to grow a bag too, hanging on extra pockets or strapping stuff to the sides with them.

Pete.

[Bmblbzzz]

<Yorksire accent>hardly out of nappies!
My expedition sack is a Lowe Kangtega I bought in 1988, ....

Ah well, here's the next thing: my expedition sack no longer is the abovementioned Karrimor. It's still going strong and sitting in the cupboard right now, strong as ever, but it was never really comfortable. So a couple of years ago I got myself a modern Osprey. I suspect it won't last as long, apart from anything else the fabrics are much thinner, but (in addition to being a bit, but not hugely, lighter) it is – most importantly – much, much more comfortable for me.

Whereas I've never replaced my Lowe because it's at least as comfortable as anything I've tried since (and being a sucker for at least trying "the most comfortable rucksack ever" to see if I'm missing anything, there have been a few).
Having said that, I've variously loaned out various packs to folk needing something large temporarily, and my Macpac Ascent has been much more popular than the Lowe, including at least one who wouldn't have given the Lowe cupboard space if I was giving it away. Like shoes, they do have to fit (my bags with frames make of flat aluminium staves I custom shape to my back).

Pete.

Conclusion 1: Comfort beats durability.
Conclusion 2: Comfort in backpacks is (almost) as personal as saddles and handlebars.

[pjclinch]

Conclusion 1: Comfort beats durability.
Conclusion 2: Comfort in backpacks is (almost) as personal as saddles and handlebars.

Yes, but for #2 I think it's proportional to pack size and carry weight. For a typical (frameless) daysack, as long as the back size is more or less a match and the shoulder straps aren't set in strange places then there's not much to go wrong, but once one starts adding weight-bearing frames fit becomes more critical.
At the size and carry capacity where we have weight bearing frames we're quite often outwith the realms of packs that folk will cycle with.

But do try on if possible, and when trying on put a representative load in it.

It'll also depend on use on the bike to some degree. For "interesting" off-road it probably pays to have something close fitting that can be strapped on at waist and chest fairly securely so it doesn't move about over bumps.
Pack profile is one I haven't given much thought to for cycling as I rarely use a rucksack on a bike. For on foot with a heavy load the idea is typically to get the load high, so with only a small forward lean the pack's centre of mass is over one's own. But for more balance critical stuff like scrambling or skiing it's generally better to concentrate weight as close to the small of the back (i.e., closest proximity to centre of mass) as reasonably possible.

On a bike those may not be great assumptions because riding position might be very different to a walking position, with the torso often more leaned forwards. I suspect (while noting again I don't ride much with a pack) that for off road bumpy stuff keeping weight close to the hips would be best, with a waist belt in place and compression straps to keep the load stable within the bag. Runners' sacks tend to fit close, and where made for the likes of mountain marathons go up to useful shopping sizes.

Bum bags give some options for modest loads. Aiguille do a 10 litre one ("The Big One") and I have a 13 litre Mountainsmith (a US brand) one, but I think a tail-pack on the bike would make more sense at those sorts of volumes if a rack isn't available.

Pete.

[Bmblbzzz]

Some outdoor shops keep sandbags in order to test backpacks with weight, even it it's not the same shape etc as a typical load. But I don't think any will let you cycle round the shop floor...

[Cowsham]

If hi-vis is important feature ( it is for me ) just check that the reflective strips or indeed the whole bag material is actually hi-vis. It may look it but test it. My brother cycling behind me one evening in darkness told me my day-glow yellow bag wasn't reflective in any way. I was a bit shocked cos I'd always thought it was reflective material.

I since bought a black bag with reflective strips. I wear bright colours so I'll still be visible in day time too. Can't really find a suitable cycling proper day glow reflective 20 to 25 L backpack.

[pjclinch]

If hi-vis is important feature ( it is for me ) just check that the reflective strips or indeed the whole bag material is actually hi-vis. It may look it but test it. My brother cycling behind me one evening in darkness told me my day-glow yellow bag wasn't reflective in any way. I was a bit shocked cos I'd always thought it was reflective material.

I since bought a black bag with reflective strips. I wear bright colours so I'll still be visible in day time too. Can't really find a suitable cycling proper day glow reflective 20 to 25 L backpack.

You can get reflective materials as the main pack fabric (e.g., https://provizsports.com/products/refle ... g-backpack), and some of them may be fluorescent, but it's more typically extra reflective tape or similar on top of a fluorescent but not intrinsically reflective fabric.

I've seen folk drape hi-viz tabards over rucksacks to make them visually louder, and you can get waterproof pack covers that come in suitably garish shades of dayglo and reflectives , e.g. https://provizsports.com/products/class ... ack-cover?. Going down that route means your choice of pack isn't restricted to bright ones.

There's also the option of sewing on reflective patches (or getting a local alteration service to do it for you), though every line of stitching makes the bag leakier, or there's the option of a semi-custom pack from a small builder where they'll add any amount of suitably bright extras according to your spec, but as noted upthread we are in the realm of uncheap for that..

Pete.