The Jam 2 sack is attracting my attention at present as I quite like the ability to cinch it down to reduce its capacity for more general day use and as I already have far too many jackets, I don’t have enough sacks; although the Angel may disagree.
However, I am at a bit of a loss as to how this performs. The usual indicator of “maximum” load is missing, at least, I can’t find it on their site, so I would grateful for any input that anyone can give as to what type of weight can be carried comfortably.
I like my sacks to be general purpose i.e. they have to earn their keep in areas other than outings.

I’ll start by setting out my “comfort” zone.
I have an OMM 32, Gregory G and GoLite Continuum packs. All state a carry load of 25lbs or 11kgs near enough.
Both the Gregory and the GoLite carry this weight with ease and with great comfort which is maintained with a few extra kg on top, probably as a result of their rigid back systems.

The OMM (foam backed) starts to collapse around the 8/9 kgs mark and is decidedly uncomfortable at 11kgs. I have replaced the foam back on the OMM with an offcut from a RidgeRest which has increased the rigidity a tad and is more comfortable for the sweaty back but does nothing for the load carrying.

So, back to the Jam 2. This is foam backed too. What sort of weight will it carry comfortably? I appreciate that this is more of a backpacking sack and that the rigidity and load carrying will be improved by a sleepmat inserted in the back, but this negates the weight equation if this needs to be applied for more general use.

Help please!

For what it's worth, Golite states a 14kg load, but the BPL review gave a 'comfortable carrying capacity' as 20lbs (9 kg).

I have not carried more than 7.5kg in mine, at this weight it is extremely comfortable - noticeably more so than the same weight in the Jam 1.

As you say, using a folded sleeping pad against the back would assist in load transfer and prevent collapse,  but be careful not to have the pad wider than the back panel, as it then prevents the hip helt from conforming to your body.

If you are normally carrying more than 11kg, I'd suggest that a pack with an internal frame would be a better choice.

thanks nsj. that seems to be in line with my own thoughts, around 9kg.

the 11kgs plus weights i mentioned are for "other" duties e.g. shopping and water carrying when on holday from shops to "home" and for shopping here in the uk.