650b: Where, When, Why

Words and Photos: Brian Anthony

When it comes to the nuances of technical bike gear, there are many (even amongst my inner circle) more adept than myself. But here I am, clacking out my impressions on the holy grail of bike componentry…wheels. So, why listen to me? Maybe you just want an honest impression without all the marketing mumbo jumbo and industry speak. Whatever your reason for trusting me with your time, understand that I’ll use the “Smile” as my unit of measure, more so than “Gear-inches” or “rotational weight”, I’ll be embarrassingly transparent, and I’ll use pretty pictures of my favorite bike in a long-format review based on a month of riding.  


Now that’s out of the way, let’s get to the other things that you might wonder about as I delve into my impressions on the Astral Outback 650b as a mixed surface wheelset. 


Dimensions: 6’ tall, 160lbs. 

Fitness/Skill/Experience: Let’s say above average, if I don’t, I’ll catch a bunch of shit for sandbagging. 

Riding Style/Terrain: 50/50 paved/unpaved riding. I’ve also mixed in loaded and unloaded and threw in a fair amount of singletrack for good measure.

Tires: This is going to drive the impressions of how any wheel behaves. I rode the WTB Byway in 650b x 47. I don’t have a stable of tires to choose from, so this seemed the most versatile option for me to conduct the test considering my plans for some very long days and big miles.


A bit more on tires…Up here in the PNW, we have a fairly robust unpaved community who generously and prolifically publish routes that bend the mind and often the derailleur of the intrepid rider. “What tires you runnin’?” asked before taking on a route has become as common as “What pressure you runnin’?” at the start of a cx race. It’s the rosetta stone to unlock any route, the measuring stick for the anticipated gnar, and key insight on how to suffer…optimally.  With these incredibly varied routes, when you throw the option of 650b into the mix you open up a whole new world of tire profiles that 700c wheels simply don’t have the clearance for. So yeah, 650B might be the ticket afterall.


The Bike: To test the Astral Outback 650b, I was on my Breadwinner B-road. The B-road, for my riding style and frequency, is a true multi-tool. Mine was designed around 700c wheels because it has to act as my road bike. It’s comfortable with slicks and fenders for year-round pavement miles. It’s my gravel bike, I’ve ridden the rowdy AF Skull 120 with 45 x 700 to a flatless top 10 finish and it’s my touring/bikepacking bike as you will shortly see. As flawless as this bike has been for me, recently I’ve started to wonder, “how would this feel if I could squeeze in 50’s?” 


Astral Outback 650b: Having ridden the Oregon Outback route, I can vouch that the wheels are aptly named. If I were to do the route again, this would be my wheel of choice without question. 

Techy stuff: I know I said I wouldn’t be super nerdy, but you may be wondering about details:

    -Hub: Astral Stage 1 with 28 spoke count

    -Weight: 1655g (60g lighter than the 700c version)

-Interior Rim Width: 25mm, creates a versatile rim that can run larger road (44mm) and standard mtb tires. Personally, I’d have no problem throwing 40mm slicks on these.

    -One big selling feature is the Astral Certainty. 

        -5 year warranty

        -Lifetime Crash replacement

        -Quick turn repairs and customer service

        -Built in Oregon

My own observations:

    -Packaged and shipped perfectly

-Pre-taped for tubeless and mounted up with my floor pump with charging booster on the first try. Valves and cassette spacer were included. 

-There were other papers in the box, I probably should have read them, but I was anxious to get out on that first ride. 


The Test:

    To date, I’ve put 665 miles on the Outbacks. I estimate the surface split to be 65% paved, 35% unpaved. Of the unpaved riding, I’d say there’s a split of 80/20 gravel road/trail riding. I’ll highlight a few of these rides. 


Day 1: Timber Logjam

Not only #newwheelday, but also my first ride with friends in like, 120 days. We’ve been quarantining pretty hard at my house, so there was much rejoicing at a distance. 

    Numbers on the day:

    41 miles

    4,500 feet

    40% unpaved, mostly good gravel. 

    A few very steep and loose sections.

First impression as we rolled out on the first ten miles of pavement was a bit of surprise, because they rolled SO WELL. I had no trouble keeping pace with the two hitters on 700c 40s. But there was an underlying plushness to the additional tire size too. It felt like pedaling a super-efficient XC bike that you knew was absorbing the bumps but not really slowing you down. Once we got on the initial gravel climb, I took a bit of pressure out. The first climb was 1600 feet with a max grade of 24%. Surprisingly, I was able to avoid losing traction while my friends who had more tread, were spinning out regularly. The increased surface area of the 47s pressured down, really coming in to play even with the Byways being a slick. 

It was descending where the Outback really showed their merit. I found them INCREDIBLY stable. I’m not going to say it’s the hand built, assymetrical spoke design that made them that way, but how else do I work that feature into a sentence? All I know, is I was dropping down ahead of the crew with confidence and playfulness and laughing out loud at just how much fun it was. The other little feature on that ride was a short section of single track with some really quick ups and downs through perpendicular ditches and sharp bends as well as a sustained chunky downhill off camber. The wheels held their line incredibly well, felt very agile, but not twitchy, and saw me back through to the finishing paved section without incident. 

First impression? I may be sold on the wheel size, and these things roll MUCH better than I was expecting. 

Next Up: After 100 local miles of errands and laps on Saltzman gravel, we decided to ride from Portland out to the local mountain bike zone, Rocky Point. Pavement to gravel to pavement to singletrack to pavement. 

    Numbers on the day:

    55 miles

    5,000 feet

    40% unpaved, gravel and single track. 

Beyond the traditional road route, we lollipopped Rocky Point and hit what would normally be XC trails. The Outback felt completely at home and, while it’s not exactly shredding on my hardtail, running sections on the drop bars was grin inducing as I learned the limits on steep descents and techy climbs. Once more, I came away feeling really impressed. The wheels felt as sturdy and confident as a mountain bike wheel, but still really light and agile. 

I will say that it was only on the steep road climb up Rocky Point where I felt I was outbiked by Matt on 700x40s. I could have added back some air pressure, but even then, a little sluggish going up the 19.5%. Once they’re up to speed though, which doesn’t take much, they love to roll. 


The Discovery Loop: I wanted to find a good test for the wheels as a bikepacking overnighter. Nothing crazy, but a new zone for me. So, I targeted a loop of the Olympic Peninsula including the Olympic Discovery Trail. Things did NOT go as planned.

    Numbers for the trip:

347 miles

    17,000 feet

    15% unpaved, gravel (only, sadly) 

    I started near Olympia, WA at 5pm and clocked 80 paved miles, riding well into the dark as I settled into the “touring” mind. My loaded kit lands somewhere in the middle ground. Some people see it as very light, others see it as a bit overkill. I see it as noticeable on the uphills. I did feel that the Outback choice was a nice stable platform for the additional weight and, since I’m climbing slowly anyway, I felt no drawback from my 700c Astral Wanderlust. If anything, a bit more stability. 

    This same stability would come into play the next morning when one of approximately 8,000 logging trucks decided put me in the ditch…literally. Riding the 101 on weekdays requires a fairly high tolerance for this kind of nonsense. The shoulder is non-existent in places, and it was through one such section where a logging rig overtook me, with traffic coming the other way, around a bend, at the bottom of a hill (read that as “Scary as shit, going too fast”). With nowhere to go and inches spare, I had to follow the line off the pavement and evasively into the ditch. I’m not going to say these wheels were lifesavers or anything. But I will say, looking back, I was glad to have been able to hold such a solid line and ride things without completely eating shit, or being run over. Safely returning the road, I pushed through a pretty big day of 157 miles. A huge portion of the Olympic Discovery Trail was closed for repair, followed by a huge portion being closed to a wildfire that popped up overnight, thus extending my miles on rte 101. But what I did ride of the ODT is remarkable, and definitely worth re-visiting. My third day, and final push to finish the route in under 48 hours definitely threw a few curveballs at me and I once more was able to push the Outbacks a bit more. Everything from packed cinder, to pock marked hardpack, to washboard, and chossy sharpness was met with comfort and easy. The wheels didn’t seem to deflect off the bigger stuff, descended smoothly, and again left me feeling really confident that I could push them into much MUCH gnarlier terrain. I find that peace of mind on these longer rides equates to at least 15 watts avg. Seriously, I did the math.


All in all, it was a thorough if unscientific exploration of the Astral Outback. Further, it was a deep dive into the world of 650B which I’ll revisitn as soon as budget allows. In my eyes, it’s the way forward for the terrain we have up here in the PNW, with the added potential of squeezing fenders and sizeable tires on at the same time. I was super impressed by this wheelset. They felt plenty light, sprightly, stable, and smooth. I wouldn’t hesitate to put them at the top of my list for purchase as your do-all, multi-terrain wheel.