Sierra Designs Flex Capicator 40 - 60 Backpack

Happened to see the SD Flex Capacitor 40 60 Backpack the other day while looking at YT videos.
afaik , it came out last fall. I haven’t yet figured out a way to justify buying one. I certainly have a collection of backpacks that are far from being worn out or obsolete . A small ULA pack, a Gossamer Gear pack , and a couple of Osprey packs.

But it seems pretty functional, and flexible. Designed with input form Andrew Skurka, thus part of the Skurka seeries of packs. Adjustable from 40 L ~ 60 L (2441ci ~ 3661ci). They classify it as ultralight but at 2.5 # not quite as UL as Z-packs ARC or other packs from MLD and other small cottage companies. Like the Z-Packs Arc it provides some air space for ventilation of your back, but with out the frame work of the Osprey packs. Very nice during warmer weather months.

About the only thing I would miss is a large mesh pocket on the back that I have on other packs.
I have a small SD tent that I purchased I’d guess 27 years ago for camping during motorcycle trips.
It’s still going, and I like their approach to design. Hmm, maybe if I can get motivated to do more back packing weekends this summer I can claim, I gotta have it. :wink:

Another view not from SD.

I’ve been looking at the FC also but agree that it lacks the exterior mesh pocket. Obviously the design prohibits the use of a pocket like that unless they could have put a bottle sized pocket on one side and a full length pocket on the other like the GG Mariposa has. That pocket could be built around those two large compression straps.

At 2.5# it better have some sort of frame. I’m not really impressed

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I think it’s an interesting pack, but I would probably rather own two different and more specialized bags- one around 35L and another around 55-60L.

I currently have several daypacks (i’m a gear whore) and one 37L (35 in name, but due to L size it’s a 37) that is working fine for me. I don’t do big trips, I don’t need a 40+…

Skurka knows his stuff though.

The SD Flex Capacitor pack does have what they call a Lightweight “Y-FLEX” suspension.
While I have gotten used to packs with the large mesh pocket on the back, and might miss that feature. I actually thought them quite weird when I first saw packs starting to use them.

Considering this pack is partly a leap of faith in Andrew Skurka’s judgement. While a lot of LD hikers are opting for packs under 2#. And following thee herd that a large mesh pocket is necessary . Andrew Skurka has done hikes of 6k to 7k miles. I think he learned some things about pack choices and desirable features while walking that far. Of course - Whether he would choose this pack for a similar hike remains to be seen.

This pack is about the same weight and capacity of my Osprey Exos 58. Both are approximately 2.62 #.
About 1.2# heavier than my Gossamer Gear pack. A Mariposa Plus, I think. I’ve had it so long I’ve forgotten the exact model name. I got it , I think, late 2008, it was when they were changing the shape of the internal frame. When ordered it had a straight u-shaped frame. I had to call Grant about something just after getting it, and he said - hey, we are changing the frame to having a slight s-curve, would you prefer that? So I exchanged them, no charge. The newer Mariposa packs are a lot different. Mine is like the one on the left in this picture.

The old and new models are compared in this blog post:

Anyway, the point being I see the advantage of going with a pack that is 1.2# lighter.
My Marmot 40 ˚ sleeping bag 1.9# : OES Tarp .977# : WB Blackbird hammock 1.55# : WB Yeti UQ .96# : Neo Air pad .893# : Spear pad extender + pads .403 # : Montane Featherlight jacket .265#.

The 1.2 # difference could make way for additional clothing. Or just save 2,000 ft-lbs of energy walking to the top of a 2,000 foot hill. That’s about 3 Snickers bars. However, I do think the heavier packs are more robust. :slight_smile:

For years I’ve used my sleeping bag more like a top quilt than sleeping bag while hammock camping. Recently I ordered an actual top quilt from Paul at Arrow Head Equipment. Apex synthetic 25˚ rating at 1.5# weight vs my 40˚ down sleeping bag. Not yet used it camping, just a couple of day hikes, set up the hammock and try it out for half an hour. Hoping it works out.

Just saw the SD Back Country Quilt and also thought it has some interesting features. The built in hand pocket and hood seem like functional ideas - Though I’m not much for camping out when it’s so cold I would only want my nose and mouth exposed to the cold. I like looking at the kind of cold from the warm side of the windows. :wink:

I’ve been the same way. Maybe I’m a little old school, but I still don’t quite understand them or why they’re a must have for so many people. My brother loves packs and gets a new one every couple of years and if a pack doesn’t have that, he won’t even consider it. I guess one thing I wonder is how quickly they’ll lose elasticity.

I haven’t bought a pack in nearly 25 years. I’ve got an old Mountainsmith, no idea what the model name is any longer. It’s 55L and expandable to 65L. However, reading this thread makes me realize it’s like carrying a house on my back, especially in light of new packs. If I remember correctly, I think it weighs about 6.5 pounds (3kg). Yes, that’s empty.

On a different yet related note, I’ve been looking for a day pack that can also double for fishing. Admittedly, I haven’t been too​ successful thus far and fear I may be searching for something that doesn’t exist.

I don’t think I’m being too picky about what I want.

  • Roughly 25 - 35L
  • Want external pocket (preferably 2) for water bottle (personally I’m not fond of hydration bladders)
  • Be long enough to reasonably carry a tenkara rod
  • Do not want an internal laptop/iPad sleeve (IMO too many day packs have them and I have no need for it)

It’s been a long time since I’ve looked for a pack and also know there are a lot of new smaller producers that have come about in the past 10 years. While I do realize that both of these are quite different from each other, at the moment, the two I’m considering the most are:

Vedavoo Spinner

Simms Waypoints backpack

Patagonia Arbor Grande
Any other ideas or suggestions out there?

Honestly my daypack for afternoons on the trail/stream is a blaze orange Patagonia Refugio 28. I would like a lighter and more fishing-oriented pack… I’m sure i’ll find something reasonable one day lol

During the summer most days I go for a day hike and go fishing.
For the day hikes I usually use an Osprey Viper 15. It is sold for cycling, but it carries all I need. Water, room for rain gear, compass and maps if playing around with them to hone my navigation skills. Or even once in while a tenkara rig.
793 ci / 13L , 1.28#. I’ve had it for several years now, red color, apparently no longer available.

For an overnight or just a day hike when I want to just set up my hammock for a lay about afternoon. Frequently I will use my ULA Conduit pack. Renamed the CDT after Brian sold ULA to Chris. Purchased it several years ago during Trail Days in Damascus, Va. from Jeff at Mount Rogers Outfitters.
3370 ci / 54L , 24 oz.

I looked at one of those the other day. While I love many of Patagonia’s things, I didn’t care for how that pack sat on my back. I’m also pretty tall too, so I think that was the reason why. I like the look of the Arbor Grande and had forgotten to add it to my list above; they just didn’t have one in stock at our local outdoor shop to try it out.

For backpacking I’ll stick with my Gregory Teton 60. It does weigh 5lbs but I have to remind myself I’m not a thru hiker. It fits me great and can handle loads over 40lbs but I don’t ever carry that much. I can lessen the load by my tent choice and my down bag is 2lbs so i can deal with it especially if I’m hiking in to fish an area that I’ll most likely stay at. It can carry all that i need for a few nights in the wilderness.

I will admit, if I don’t have the Refugio loaded up (puffy down jacket does that just fine), it will usually sit kinda funny on my back. I’m 6’2" and skinny.

That Arbor Grande looks nice.

I will admit I think their Black Hole bags look cool, and if i was buying a daypack/small overnighter travel (not UL b-packing) bag today, I’d prob get one of them.

Oh snap just found my “fishing pack”

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The Versalite 30 looks pretty decent and is a good price too.

I nearly bought a Versalite 30 (or 40) a couple months back.
I wound up getting a Gregory Miwok 34 on sale from Backcountry for really cheap.
Similar pack, with very simple design, frameless, and just over 2#. It was on sale for $74 and I think I had a coupon or something that got it even lower than that. I’m very happy with the bag for the price I paid, but would’ve been happy at full retail I think.

Zombie thread.

Went on a couple hikes with the Gregory Miwok. I don’t like frameless packs. I need more support/suspension.

On my summer family trip to Japan I mostly used duffels, we didn’t do much travel on foot where we needed to carry much, but even moving through airports and such, I realized it’s not for me lol. I needed a bigger, better backpack. This winter I’m moving to Korea and taking a week along the way to hit Tokyo, Hanoi, and Bangkok. I need a better backpack for sure!

Wound up finding a great deal ($125) on the Flex Capacitor, and jumped on it. I haven’t actually packed anywhere with it yet, but loading up at home and walking around, I’m quite impressed. The frame does an amazing job and putting the load on my hips, the belt is comfortable, and the overall pack design should work great at least for my somewhat specific usecase.

For reference, I’m 6’2" and 155lbs. I got a M/L size pack and a S/M belt. Seems the perfect fit, actually the best fitting pack I’ve probably ever had. This is also the fanciest or at least highest price pack I’ve ever had too, splurged a bit.

The plan is to load it up with as much as it can carry, and decide at that point if I need to do a little duffel action I will go from there. Uniforms, all sorts of crap lol.

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I’m looking at a little different design than my Osprey Porter 46.

This Gregory pack has my interest.

That Gregory looks like an awesome travel pack, very streamlined.

Adam I’ll message you

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If you’re looking for a travel pack you might consider the Rick Steves Classic Travel Backpack.
I have a few of the RS products and have found them to be the best products for traveling I have ever purchased. I don’t have the CTP, but have a similar capacity (2500 ci = 41L) Convertible Carry-on (with the optional padded shoulder strap) - the current version has a couple of update features mine doesn’t have. Very good for vehicle travel not for outdoor travel.

The Flex Capacitor does look cool. That Y frame keeps a gap for airflow against your back. I was chatting about this with Adam Klagsbrun who loves the Zpak bags because of that feature. I don’t think Adam is on here so I thought I would share that. I aspire to one day backpack but do not know anything personally…Adam K on the hand knows a lot.

On the daypack end I saw this on Kickstarter that caught my eye…interesting idea…

airflow is very important to me. Right now i’m in the south (AL) and am headed to Korea then Okinawa… all tropical humid places. This will prob be more of a travel pack for me than actual backpacking, but I will hopefully get some camping in with it. Most of my camping is car-camping, and the duffels work just fine for that- easier for tent/gear organization and just pulling out of the trunk.

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