We got these photos of a Steve Potts titanium road/cyclocross bike from Mike Valley at Black Mountain Cycles, one of our Rohloff dealers in Pt. Reyes, CA. The frame was on display at Steve Potts' booth at NAHBS, and the bike was assembled shortly after the show. Steve made the titanium frame and stem, as well as the steel fork. The goal was a multi-purpose bike that could be used on pavement with skinny tires or dirt roads with larger tires. S&S couplings allow the frame to separate into two pieces that can be packed into a box that meets airlines' maximum baggage dimensions, saving the exorbitant fees that some airlines charge to transport a bicycle. Titanium is a great frame material for a travel bike because it is scratch, dent, and chip resistant, so it won't get banged up in transit. The Rohloff SPEDHUB 500/14 offers a travel-friendly drivetrain that doesn't have any derailleurs hanging down that could potentially get damaged. Paragon Machine Works sliding dropouts provide a means for tensioning the chain and anchoring the hub's axle.
The Rohloff SPEEDHUB 500/14 twist shifter is mounted onto the end of the drop handlebar through the use of a Hubbub adapter. Rohloff only offers one shifter for their hub, which is designed to fit onto a 22.2mm diameter mountain/touring/commuting handlebar and does not fit directly onto a 23.8mm road handlebar. Hubbub offers a simple solution to connect the stock shifter to a road bar with an adapter that uses an expansion wedge to hold it inside the handlebar. When using their adapter, the shifter can be positioned at the end of the drop section with a full handlebar or a section of the handlebar can be removed so the end of the shifter ends up where the end of the handlebar used to be. With the shifter at the end of the bar, the cables can be routed around the head tube as with this build or redirected under the bar tape by using a pair of flexible brake noodles. We find the cable routing used here to be much more travel friendly because the shifter can be easily separated from the handlebar and kept with the front half of the frame for easier packing.
This bike uses the internal cable mechanism from Rohloff, which we don't see too often since it's not directly compatible with disc brakes. With this system, cable housing is run from the shifter to a cable housing stop on the frame, then exposed shift wires extend past the stop to the female end of quick-connect bayonet links. The male ends of the bayonet links connect to wires that spool around the shift axle on the SPEEDHUB 500/14. When removing the wheel, the bayonet links easily separate with a quarter turn twist, and reattach during installation by pushing together until they snap. The cables coming from the shifter stay on the frame while the cables coming from the hub are removed with the rear wheel. This is the original cable attachment mechanism and an available option for non-disc hubs. It weighs a little over 100g less than the external cable mechanism, and costs roughly $150 less.
On this bike, the internal cable mechanism made it easier to work with the S&S couplings. A custom dual-cable housing stop was welded to the bottom of the left chainstay with a slot for each cable. When packing the bike, the bayonet links are separated, the barrel adjusters are unthreaded from the stop, and the shift wires are passed through the slots in the stop so that the cables coming from the shifter can fully separate from the back end of the frame.
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Build details
Frame: Steve Potts titanium cyclocross with S&S couplers
Fork: Steve Potts steel
Headset: Chris King NoThreadset
Stem: Steve Potts titanium
Handlebar: Salsa Cowbell
Shifter: Rohloff
Shifter Adapter: Hubbub
Seatpost: Thomson Elite
Saddle: Fizik Aliante
Front Hub: Paul Components High Flange
Rear hub: Rohloff SPEEDHUB 500/14
Spokes: DT Swiss Competition
Nipples: DT Swiss brass
Rims: Mavic A719
Tires: Continental Grand Prix 4-Season
Skewers: Shimano XT
Cranks: White Industries ENO
Bottom Bracket: Phil Wood
Chainring: White Industries
Brakes: Paul Components Touring Cantis
Brake Levers: SRAM 900
Water Bottle Cages: King Cage Titanium
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