04 August 2014

Jeff Jones Titanium Space Frame With Rohloff SPEEDHUB


This bike was built for a local customer who came to us looking for a unique frame that was comfortable and versatile enough for the different types of trails near his home in Oakland, CA. He had his eye on a Jeff Jones Titanium Space frame, which has long been recognized as one of the most distinctive titanium mountain frames.

Our customer planned to explore the Bay Area on various trail rides and weekend trips. From long rides on hilly doubletrack to weekend bike camping trips on paved and dirt roads to quick twisty singletrack, he wanted a bike that would do it all. After talking with him about his riding style, we put together a collection of top-notch components  including a Rohloff SPEEDHUB 500/14  that would match the aesthetics of the titanium frame and last him for years.





Jeff Jones is a renowned framebuilder who designs distinctive frames, forks, and handlebars in Medford, Oregon. He has gained a devoted following for his designs that are innovative in both their functionality and their looks.

The Space Frame is his flagship design  a lightweight titanium frame that is quick-handling and good at absorbing bumps, even as a fully rigid bike. The frame’s main innovation is in the top tube area, which consists of three tubes  two of which transition to serve as the seatstays. Both seatstays extend from the rear wheel all the way to the headtube, with a smaller curved tube that connects from the seat tube to the head tube. This design is meant to increase lateral stiffness – because the seat stays remain wide and extend across the length of the frame – and also allows the seatstays to flex vertically, creating some minimal suspension in the frame itself. The wide seatstays also allow for larger tire clearance, while heavily manipulated chain stays also add to the suspension effect.





The frame’s low top tube provides plenty of stand over clearance for confidence on rocky, rooty trails, while the short rear end puts the rider’s weight over the back wheel to keep the front wheel lighter and more maneuverable in technical sections.  An eccentric bottom bracket comes standard, which offers simple chain tension adjustments and makes this frame a good match for the Rohloff SPEEDHUB. The truss fork is designed to minimize the front-to-rear flex that occurs on most rigid forks in response to braking, which can negatively affect handling.


Once we had the frame in hand, we set to work on the wheel build. We started with a set of Surly’s Rabbit Hole rims, which are 50-mm wide to spread out the tires and provide more traction and cushion. We laced the rims to a black Rohloff SPEEDHUB in the rear and a black Schmidt SON28 dynamo hub in the front.

While this wheelset is built around 29+ rims, the frame was designed before Surly created the 29+ standard, and the frame won't clear a 3" wide tire. As a result, the rear tire size was limited to a standard 29'er tire - a Geax Saguaro 29x2.2” in this case - while the front got a Surly Knard 29x3.0” tire.

The Jones truss fork cleared the large front tire easily, but its 135mm dropout spacing rules out most dynamo hubs, which are typically only available with 100mm spacing. Fortunately, Schmidt offers a fatbike-specific version of their popular dynamo hub with a 10mm axle and 135-mm spacing to fit the most common fat bike fork standard. However, since the dropouts on the Jones fork are 9mm wide, we were faced with trying to modify the fork to fit the 10mm hub axle or modifying the axle to fit the fork. The prospect of fixturing the fork and machining the dropouts proved to be too complicated, so we took the front hub to a local machine shop and had them turn the axle down to 9mm to fit into the fork.




Our customer was first interested in the Rohloff SPEEDHUB because he wanted his bike to be as simple and worry-free as possible. The SPEEDHUB has the gear range of a typical mountain bike derailleur system with the simplicity of a single-speed set-up. The gear unit offers fourteen evenly-spaced speeds by utilizing planetary gears that revolve around the axle. Its shifting components are sealed within the hubshell and protected from the elements, making the hub much more durable than any cassette and derailleur setup. There are no external shifting components to bend or break, and no cable tension adjustment required to get the hub shifting correctly. It simply works reliably, time and time again.

Our customer stressed the importance of shifting reliability. With the SPEEDHUB, the gears can be changed at any time whether a rider is pedaling or not, making it easier to keep a constant cadence, navigate technical singletrack, or tackle sudden changes in a hill’s grade.



To compliment the frame, we selected a unique set of components with a focus on comfort, ergonomics, and durability. We installed Jeff Jones H Bars, which have an ergonomic swept back grip position as well as a complete loop on the front of the bars for additional hand placement or accessory mounting options. On the handlebars, we installed Ergon’s GC1 grips, which feature a palm rest to combat hand numbness. Rounding out the bike’s cockpit, we also installed Magura’s lightweight MT6 hydraulic brakes. The Selle Anatomica Titanico X leather saddle has an already-broken-in feel right out of the box due to its cutout and split hammock design. VP's Vice platform pedals, Raceface's Turbine cranks, and a Thomson stem and seat post rounded out the build.

When our customer came to pick up his bike he was thrilled. His new ride inspired him to plan some weekend camping trips, singletrack epics, and fireroad grinds in the East Bay and Marin hills in the near future. If you’re looking for a similar bike of your own, please contact us to talk about what we can build for you.

Build Details:

• Frame: Jeff Jones Titanium Space Frame
• Fork: Jeff Jones Truss Fork
• Headset: Chris King
• Stem: Thomson Elite X4
• Handlebar: Jeff Jones Loop H-Bars
• Shifter: Rohloff Twist Shifter
• Grips: Ergon GC1, Deda Logo Bar Tape
• Seat post: Thomson Elite
• Saddle: Selle Anatomica Titanico
• Seat Clamp: N/A
• Front Hub: Schmidt SON28 135mm
• Rear hub: Rohloff SPEEDHUB 500/14
• Spokes: Sapim Race
• Nipples: Sapim Brass
• Rims: Surly Rabbit Hole
• Tires: Surly Knard 29x3” front, Geax Saguaro 29x2.2” rear
• Cranks: Race Face Turbine
• Pedals: VP Vice
• Bottom Bracket: Race Face
• Chain ring: Race Face Single
• Rear Sprocket: Rohloff
• Chain: Wipperman Connex 8sX
• Brakes & Levers: Magura MT6
• Rotors: Magura Storm


4 comments:

  1. What headlight did you use? Do you have any experience with the dynamo headlights when used with 29+ wheels/tires? Does the slower revolution of the bigger diameter tire adversely affect the light?

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    Replies
    1. We installed a Schmidt Edelux light after the photo shoot. We've built quite a few 29+ bikes and haven't noticed any difference in performance compared to a bike with a smaller wheel.

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