The SunTour Hole Shot was conceived as a derailleur for BMX bikes. It was designed to operate over a two speed freewheel.

Obviously inspired by the Coelacanth, SunTour tried to incorporate as much dinosaur DNA as possible. Despite being produced in 1980 it is a sliding rod design, with the pulley cage moved by a bell-crank reminiscent of Simplex’s designs from the early 1950’s. It mounts on the drop-out, but operates under the chainstay - this time in a curious echo of the 1950’s Altenburger and even older Nivex designs - although in anticipation of SunTour’s own S-1 and SX-100 designs. The single sprung pivot is on the opposite side of the guide pulley from the tension pulley (not between the pulleys as would be more normal) - again an echo of the Altenburger design.

Quite why BMX bikes should need such a radically unique design is unclear to me - but that is true about many aspects of BMX - a sport that is rivaled only by golf in the eccentricity of its rituals and dress code. ‘BMX - the golf of youth’ - now there’s a slogan.


  1. Brand: SunTour

  2. My category: SunTour - weirdness

  3. Country: Japan

  4. Date of introduction: 1979

  5. Date of this example: unknown (no two letter date code)

  6. Model no: 2900

  7. Weight: 247g including integral hanger plate

  8. Maximum cog: 24 teeth

  9. Total capacity: 12 teeth

  10. Pulley centre to centre: 41mm

  11. Index compatibility: friction

  12. Chain width: 3/32”?

  13. Material: steel


SunTour Hole Shot (2900)