Soma Fab Updates B-Side 650B Mountain Bike – Plus New Stainless Cyclocross, Youth Road Bikes & More!


Soma Fabrications has been quite busy lately, releasing several new bikes (and parts) over the summer and now this 650B update to their hardtail and some impressive looking kid’s 20″ road bikes.

The B-Side 3.0, shipping in January, gets tweaked geometry to move it from XC race toward today’s more common “trail” style riding. In doing so, they set it up to work with current 650B specific 100mm and 120mm forks from Fox and Rockshox. Head angle is now at 69/68 degrees. It also upgrades to a machined 44mm headtube to work with tapered forks and, along with a sturdier downtube, boost stiffness. Chainstays are a bit shorter, and it can still be run geared or singlespeed thanks to Tange/IRD sliding steel dropouts.

More details on this, their gorgeous Triple Cross stainless cyclocross bike, kids bikes and a rando, below…


The B-Side’s frame is Tange Prestige butted tubing up front with chromoly stays.


As a followup to their Double Cross, the new KVA Stainless Steel Triple Cross ups the speed and “need” quotient quite a bit. Geometry is racier with a lower bottom bracket, putting you more “in” the bike than on top of it…which tends to be the trend these days as racing ‘cross bikes are being called to serve in gravel road races, too.


The tubing is KVA’s air-hardened MS2 and is both strong and light while being corrosion resistant. It’s fillet brazed and the joints are left visible among the mirror polished tubes. It’s disc only, and had clearance for up to a 700×41 tire. Contrasting those modern features are a 68mm English threaded BB and 1-1/8″ straight steerer tube. Available as a frame only, and they’re making up to 100 this year…and maybe not even that many. Get on the list now if you’re digging it.


Not wanting to leave the kids off the back, the new Bart and Lisa are versatile 20″ bikes. They’re available as framesets in polished chrome for the boys and pink for the girls (though you could put either under any gender). They offer a mini-kit with kid-sized parts to help get the build started (includes a shallow drop 33cm wide handlebar, 140mm 40/34 double crankset, alloy wheelset and brakes), then just kit it out with standard modern 9-speed components and other standard parts. Standover height is 24.5″.


Check their blog post for more build and action pics and some parts ideas.


Introduced this summer, the Grand Randonneur shows that not all the 650B action is on mountain bikes. This tourer comes with its own lugged fork and has all the eyelets and mounts you’d need for loaded bicycle travel. That includes three water bottle bosses and a pump peg.


The frame is made of butted Tange Prestige in the traditional small diameter tubes steel bikes are known for. It’s even got a 1″ threaded headset for good, old school measure.


mike - 10/25/13 - 12:09pm

Just ordered the old B-Side!!! Dammit

King County - 10/25/13 - 1:24pm

I love the stainless! With the B-Side, (and similar versatile bikes), I am not a huge fan of them because it is always a compromise derailleur or no-derailleur. Its either no cable guides, or cable guides when you want a clean look; extra weight of an ecentric or bulky convert-droputs, etc. I prefer a ‘dedicated’ bike

g - 10/25/13 - 3:43pm

i dig it all except for the hourglass headtube on that b-side. When soma makes a long travel, short stay 29er i’ll buy it.

brent - 10/25/13 - 10:25pm

Just give me that rando fork…

Ajax - 10/25/13 - 11:25pm

Do you know? If those replaceable dropouts on that B-Side 650b are replaceable with the slider Paragon thru axle dropouts? Now, THAT would be awesome!

…..but alas, Soma doesn’t know the greatness of thru-axle. I called them and asked them if those dropouts were replaceable with the Paragon slider thru axles, and they had no idea.

rico - 10/26/13 - 12:37am

Woah those kids’ road bikes are sweet. Looks like they will fit really well with kid proportions and riding style. I could see my daughter in the drops on the pink one tearing away from me, scary!

Loyd Flanders - 10/26/13 - 9:04am

What is the rear dropout spacing on that sweet staino rig?

Yoseph - 11/14/13 - 6:59pm

Ajax, I would say you can replace the slider dropouts with the paragon thru axle version. I would actually call paragon to confirm but I don’t see why not. I was actually on the same thought process when I first saw this frame. I am going to buy one and convert to the 142×12 thru axle for sure!

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