The SunTour Hole Shot was designed 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 rivalled only by golf in the eccentricity of its rituals and dress code. ‘BMX - the golf of youth’ - now there’s a slogan.

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1. •Brand: SunTour
   

2. •My category: SunTour - weirdness
   

3. •Country: Japan
   

4. •Date of introduction: 1980
   

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

6. •Model no: unknown
   

7. •Weight: 247g including integral hanger plate
   

8. •Maximum cog: 22 teeth?
   

9. •Total capacity: 8 teeth?
   

10. •Pulley centre to centre: 41mm
    

11. •Index compatibility: friction
    

12. •Chain width: 3/32”?
    

13. •Material: steel
    

0344/L