02 August 2012

Rohloff-Equipped Soma Juice 29'er Mountain/Touring Bike


This Soma Juice 29'er was built for a customer in San Jose, CA as a multi-purpose bike.  The goal was to build a moderately priced bike around the Rohloff SPEEDHUB 500/14 that was capable of off road use, running errands, and light touring.  This type of bike represents a growing category often described as an adventure bike.  Adventure bikes are typically built around a frame with mountain bike geometry, but can go in many directions: mountain or road handlebars, rigid or suspension fork, more off road or more touring oriented features, etc.  The Rohloff SPEEDHUB 500/14 complements an adventure bike by providing a reliable, low maintenance drivetrain so the rider can spend more time riding and not have to worry much about adjusting or maintaining the bike.


The build kit focused on comfort, durability, and value.  A mid-level Rock Shox suspension fork, Cane Creek suspension seat post, and an upright riding position give the rider plenty of comfort.  The US-made Selle Anatomica Titanico saddle feels good out of the box with a thick leather cover that provides good long term wear life.  Ergon grips have a wide palm rest that reduces hot spots.  Tires were chosen with a moderate tread that could provide decent traction on unpaved surfaces while still rolling on the pavement without too much resistance.

Brakes are Magura's excellent MT2 hydraulic units.  Positioned as the entry level model in Magura's 4-tier MT lineup, the "2" model offers great performance at a price that is not much higher than a mechanical disc setup.  They are lightweight and have great stopping power and durability.  Magura offers a 5-year warranty on their brakes, which bests most if not all other manufacturers' warranties.

For the wheels, we laced the Rohloff rear hub and a Shimano XT front disc hub into Velocity Dyad rims using Sapim Laser spokes and brass nipples.  We use the Dyad rim for many applications, and in this case, it offered a good combination of weight, strength, adequate tire support, and price.  The Laser spoke is a thin double butted model that was chosen for this lighter weight rider for improved comfort over a thicker spoke.  The inexpensive Shimano XT front disc hub is a standard value-priced option.  These 6-bolt hubs use loose ball bearings and can hold up to many thousands of miles of service with some routine maintenance.

The chromoly steel Soma Juice frame was chosen as a value-oriented option that was a good match with the Rohloff SPEEDHUB 500/14.  The steel tubes provide a comfortable, durable frame and for 2012, the Juice model was updated to include sliding dropouts instead of the horizontal ones previously used.   Sliding dropouts offer an easy method for tensioning the chain as well as anchoring the Rohloff SPEEDHUB 500/14 axle to the frame when combined with our Monkey Bone brake adapter.  The only thing missing on this frame are Rohloff cable guides, but the cables are easily held in place with zip-ties.

With the update of the Juice model, Soma now offers inexpensive, Rohloff-friendly frames for the three common mountain bike wheel sizes - Analog (26"), B-Side (27.5"/650B), and Juice (29"/700c).  These are some of the few stock frames on the market that offer sliding dropouts, which is even more impressive considering their low price.  Most frames in this price range use horizontal dropouts, which are cheaper to manufacture, but have some drawbacks, especially when using disc brakes.  We much prefer adjustable dropouts or an adjustable bottom bracket to adjust chain or belt tension.

The Soma frames are a good choice for a value-oriented Rohloff bike build and a viable alternative to a Surly Troll (26") or Ogre (29"), which are also popular Rohloff frames (see example here).  The Surly frames have more features than the Soma frames - bigger tire clearance, accommodates disc or rim brakes, more mounting points for racks, fenders, and even their trailer, and multiple cable routing options - but the Soma frames have adequate features for most rider's needs and we find the installation and adjustment of the rear wheel to be much easier with the Soma frames.  Depending on your intended use, the Soma may be the better choice.  Contact us to help determine which frame will work best for you.


Build details
  • Frame: Soma Juice CroMoly steel
  • Fork: Rock Shox Recon Gold
  • Headset: Cane Creek S3
  • Stem: Soma Shotwell
  • Handlebar: Salsa Bend 2
  • Shifter: Rohloff
  • Grips: Ergon GP1 for Rohloff
  • Seatpost: Cane Creek Thudbuster LT
  • Seatpost Collar: Salsa Rack-Lock
  • Saddle: Selle Anatomica Titanico
  • Front Hub: Shimano Deore XT
  • Rear hub: Rohloff SPEEDHUB 500/14
  • Spokes: Sapim Laser
  • Nipples: Sapim Brass
  • Rims: Velocity Dyad
  • Tires: CST Critter
  • Skewers: Shimano XT
  • Cranks and Bottom Bracket: Shimano Deore
  • Chainring: Race Face Single
  • Chain: Wippermann 808
  • Brakes: Magura MT2
  • Rotors: Avid G2 Cleansweep 160/180mm
  • Rear Brake Adapter: Cycle Monkey Monkey Bone

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