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When lifelong cyclist and career journalist Kurt Genshiemer built up his first electronic shifting bike, he wanted it to be something truly special. So he contacted the crew at Mosaic Cycles, who handbuilt him a bespoke titanium GT-2 AR road frame in Boulder, Colorado. Outfitted with SHIMANO’s all new 105 Di2 12-speed group set, the bike and build are an electrifying combination for this Analog Man’s maiden voyage into the electronic future. Here is the bike that Kurt used while reporting on a story about the Hilly Hundred in Southern Indiana. The full article appears in SHIMANO’s Cadence book of road cycling tales.

Kurt’s Mosaic GT-2 AR features titanium construction and a 105 Di2 groupset, photographed where cycling really took hold of his life, under the deciduous canopies of Southern Indiana.

SHIMANO’s R7100 series, 105 Di2 drivetrain, in all its glory.

A 12-speed cassette with an 11-34 cluster has the perfect gear for all the undulations around Bloomington, Indiana.

The extended cage on the R7170 Di2 rear derailleur is also compatible with SHIMANO’s new HG710 11-36 cassette for even more help when the going gets steep. The latest generation of Di2 also features a charging port on the rear derailleurs.

Precision craftsmanship on the rear end of the Mosaic GT-2 AR makes for clean lines, smooth wire routing and the stiffness and reliability of a 12 mm thru axle.

A redesigned look and optimization for 12-speed chain rings make the 105 crank punch far above its weight in aesthetics and shifting performance.

The R7170 Di2 front derailleur has a powerful motor delivering reliable and precise front shifts even under load. Kurt runs a 50/34 tooth setup for the steep climbs of the Hilly Hundred.

The bespoke Mosaic, handmade in Boulder, Colorado, features a brilliant green finish with a painted carbon fork to match. PRO carbon bottle cages add some composite aesthetic and lightweight holding power to the build.

Even the seatpost clamp features the attention to detail that defines Mosaic’s builds.

A PRO Vibe Alloy seatpost keeps the cockpit metal, while the setback option helps dial in the bike fit. Kurt chose the Turnix Team for its scooped profile that matches his flexible riding position.  

The wireless communication between the shifters and derailleurs cleans up the cockpit, letting details really shine like the intricate Mosaic headbadge.

 Kurt’s 110 mm PRO Discover Alloy stem provides a nice blend of stiffness and security for reliable steering. PRO offers the stems in lengths from 70mm to 110mm.

Sleek ergonomic hoods, wireless shifting and powerful braking make the R7170 Di2 levers a solid choice for long days in the saddle.

A 12 mm front thru-axle maximizes the lateral stiffness and improves the braking performance on the all new RS710 carbon 12-speed wheels.  

The Di2-equipped Mosaic is the perfect bike for adventures like the Hilly Hundred, pictured here under the full power of Kurt’s fully furry legs. 



Custom MOSAIC GT-2 AR 

  • Frameset: Mosaic GT-2 AR Titanium
  • Shifters:  105 Di2, R7170 
  • Brakes:  105, R7170 
  • R. Derailleur:  105 Di2, R7170 
  • F. Derailleur:  105 Di2, R7170
  • Cranks:  105, R7100, 50/34 T
  • Cassette:  105 R7100, 11-34 T
  • Chain:  CN-M7100, 12-Speed
  • Wheels:  RS710, C46 Tubeless
  • Tires: Continental Gatorskin Tubeless, 32 mm
  • Rotors:  Rt70, 160 mm/ 140 mm
  • Bars: Pro Discover Gravel Flared Aluminum,  44 cm
  • Stem: Pro Discover Alloy, 110 mm
  • Seatpost: Pro Vibe Alloy
  • Saddle: Pro Turnix Team
  • PEDALS:  105, R7000 SPD-SL

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