Soma B-Side - 650B build project report and showing of!

Ravewar

Thought you might be interested to hear how I got along building a Soma B-Side with its recommended 650 Wheels.

The frane and fork were ordered through Heart of Wales Bikes, my local bike shop who helped immeasurably during the build. Heart of Wales Bikes are subsequently selling Soma frames and 650B White Brothers forks online. I also used Dinosaur Bikes (Looked for address but they seem sadly now defunct) for the wheels rims.

The outcome: the parts took some tracking down, especially wheel rims. I'm not sure about the choice of tyres, because whilst the acing Ralph's seem fairly available, there seems to be little other choices, I don't know whether that will change. They have also kindly put my bike there for everyone to see on this page.

The rest of the bike - very much a lash-up of what looked nice or could get good prices on. The singlespeed Surly Whirly chainset is certainly different and was chosen for the ability to change its configuration if my needs change. The bike was built as a singlespeed but have rebuilt as an 11 speed Alfine mule. Unfortunately I have just finished the Alfine and cannot report performance.

Would I do it again? No. I think the frame might have genuine interest in building a modern "roughstuff" tourer rather than mountainbike. In that role it could also use the traditional British 26" roadster tyres and rims, which still seem more readily available in the UK than the continental 650B. However as tyre and rim choices improve this bike can only become more versatile. However I would definitely consider getting another SOMA frame as the B-side is light, and its design and paint make it a nice talking point when I ride it.

Notable points are:

Frame Soma B-side, Medium
Fork: White Bros Magic 650B (Only 80mm!)
Crankset: Surly Whirly SS
Brakes: XTR
WTB saddle and headset
Wheels: local bike shop hand built, consisting of
Wheel rims: Velocity Blunt
Hubs: XT centrelock (rear changed to Alfine 11)
Tyres: Schwalbe Racing Ralph

Ravewar

I've linked to the picture. Wanted to take some fresh ones, but the weather is not the best for outdoor photography right now!

WebbyM3

Is that a light on the bars?

Ravewar

After what to me was quite an involved build, I did not expect the first question to relate to the lighting arrangements which had simply been thrown on the bike to allow a spin round the block after dark Yes, that is a Cateye headlight on the bar, with a rear one on the seatpost. The bike played its part in the snow last year (when it was a singlespeed), we will see how it does this year if we get similar conditions.

I got some more pictures hosted for your viewing pleasure, this time with the Alfine transmission. See below.

WebbyM3

Sorry about the question :P it was just the fact it was so big that made me notice it. Nice bike by the way :P whats it ride like with 650b wheels?

Ravewar

Yeah, it rides alright. I took it to the Real Ale Wobble in Llanyrtd sunday before last and whilst I made it round the course I think the fork needs a bit more tweaking. So whilst showing potential I don't yet think I am getting the most out of it.

The frame is very flexy too which is a bonus at the undampened rear end but does not provide a stiff platform for the front fork to do its thing - just as well I am not heavy and it's quite a short travel fork.

The tyres also need swapping for knobblier ones at this time of year, which is where I start to run into the lack of choice relating to the 650B size.

Regards.

gregsd

Sorry for the thread resurrection but I've had my eye on B-side for awhile now and just found this thread! How have you found the bike since your last post? Have you noticed any difference with the wheels size?

Greg.

Ravewar

Sorry for the thread resurrection but I've had my eye on B-side for awhile now and just found this thread! How have you found the bike since your last post? Have you noticed any difference with the wheels size?

I have played around with the front fork pressure and made it ride a great deal better. Still not got more aggressive tyres which limited the utility of the bike during the winter months, and perhaps hides the full potential of the machine. But I like the way it rides. One recurring theme however which has limited my use of the bike is the extended debugging period relating to the internal hub control cable. Although the Aline allows it to be orientated for a seat-stay cable routing it does not seem happy in this position and really wants chainstay routing where the cable does not have to cross the chain close to its entry into the gear selector. So I recommend derailleurs for anyone considering a build project, although a Rholoff might work.

Soma have subsequently released a Mk2 B-Side with slidey drop-outs which make chain tensioning easier but they still seem committed to a seat-stay cable routing.

Ravewar

Update for Greg: still going well and my familiarity with the machine is increasing with a gap due to the lousy weather, however I'm hoping to find some lumpier tyres later this month and will post again here when I do...

gregsd

Thanks for the update. Seems like you might have more choice for all things 650b next year! Seen a 2ndhand wheelset on another forum, but thought they price was a bit high, but still tempted to give em a try.

Ravewar

I went out for a ride with the MTB group who ride from Cycle Tech in Builth Wells and they were very interested to see a 650B bike first hand. Bike performed well except for one chain-throwing incident. Probably my fault in not getting the chain sufficiently tight, but Heart of Wales Bikes now seem to be selling a newer B-side with sliding dropouts which will make this less likely to happen, and one hopes easier to fit if it does.

Surly crank a bit loose now, hopefully the Mr/ Whirly crank won't be the next problem area...