19 February 2012

Rohloff-Schmidt Conversion on Spot Acme

We recently did this Rohloff-Schmidt conversion on a Spot Acme for a customer in Sausalito, CA. He regularly commutes into San Francisco by bike and was looking for a new ride that was lightweight and stylish. As with most of the customers that contact us, low maintenance, reliability, and functionality were important considerations for this build. With the many hills in the Bay Area, wide range gearing is critical, and the 3-4 month annual rain season makes a belt drive ideal and fenders a necessity. The customer wanted to use a Rohloff SPEEDHUB 500/14 with a Gates Carbon Drive belt system and a Schmidt SON dynamo powered lighting system. With the component set determined, we looked for a frame well suited for commuting.

The Spot Acme model was conceived as an urban bike with a relaxed road bike geometry, a swept-back handlebar for upright riding position, fender and rack mounting points, an internal-gear hub (Shimano Alfine 11), and belt drive. The Acme frame uses a pivoting dropout to tension the belt and an opening point for belt insertion located towards the top of the right seat stay near the seat stay bridge.

The customer liked the Spot frame, but wanted to upgrade several components, notably the rear hub. Since the frame is not sold separately, we started with the complete bike. The wheels, brakes, shifter, cranks, and bottom bracket were pulled and replaced with parts that the customer wanted - Rohloff SPEEDHUB 500/14 rear hub and shifter, Schmidt SON28 dynamo front hub, Magura MT2 brakes, and Race Face Turbine cranks and bottom bracket. Supernova lights were also added (E3 Pro with Terraflux asymmetric lens and E3 seat post mount Tail Light) as well as SKS P35 fenders.

For the wheels, we laced up the Rohloff and Schmidt hubs into Alex TD17 rims using Sapim Race double butted spokes and brass nipples.  The Race model is a standard double butted spoke from Sapim that is the default spoke for most wheel builds.  The Alex TD17 rims are inexpensive disc-specific touring/commuting/mtb rims that build into solid wheels.

Build details
  • Frame: Spot Acme Aluminum
  • Fork: Spot Carbon
  • Headset: Cane Creek 40 Internal
  • Stem: Spot
  • Handlebar: Spot Sweptback
  • Grips: Ergon GP1 for Rohloff
  • Shifter: Rohloff
  • Seatpost: Spot
  • Saddle: WTB Rocket V
  • Front Hub: Schmidt SON28 2012
  • Rear hub: Rohloff SPEEDHUB 500/14
  • Spokes: Sapim Race
  • Nipples: Sapim Brass
  • Rims: Alex TD17
  • Tires: Ryder Elite
  • Cranks: Race Face Turbine
  • Bottom Bracket: Race Face Turbine
  • Chainring: Gates Carbon Drive Center Track Pulley
  • Chain: Gates Carbon Drive Center Track Belt
  • Brakes: Magura MT2
  • Rotors: Avid G2 Cleansweep
  • Fenders: SKS P35
  • Lights: Supernova E3 Pro Terraflux & E3 Tail Light


  1. This comment has been removed by a blog administrator.

  2. That's a beautiful setup. What's the final price tag?

    1. The price tag was close to $5.5k minus whatever the customer recouped selling the stock parts on ebay. It would have been nice to start with just the frame (also more economical), but it wasn't available.

  3. I'm really interested in setting up my Rohloff with a Center Track system but Gates are insisted on an expensive frame test before they release the parts.....It's a one off, custom steel build and seems a lot to just check the strength of a frame I know is easily strong enough! Do you have a simpler way round than this?! Also, did you use the torque arm because the rotational torque would be too much for the pivot dropouts to handle? Cheers! Oh, and it's gorgeous! (I'm in the UK btw!)

    1. The test is free in the US. Not sure what it costs in the UK.

      The torque arm is used because the frame has a post mount disc interface, which means the Monkey Bone or Speedbone will not work.

  4. This comment has been removed by the author.