The challenge

  • Description of the application: Exercise Bycicle
  • Former type of transmission: chain, V-belt and timing belt
  • Type of users: Private / Professionals sportsmen / Fitness centres
  • Complaints: High noise level / Shock‐loading / Maintenance

Problems & Consequences

  • Noise: Clanking of the chain and whistling of the timing belt can discomfort the user and give an impression of a low quality bike.
  • Shock‐loading when pedalling: The teeth of the chain, or of the timing belt, are seizing up and the V-belt is slipping, which cause irregularities when pedalling and discomfort for the user.
  • Drive dimensions: V-belts require large pulley diameters, which limit design opportunities.
  • Maintenance: chains need regular grease and oil treatment.

Solution & Benefits


  • Silence: The lengthwise grooves of the Poly V® belt optimise its area of contact with the pulley. The whistling due to escaping air trapped by the timing belt profile is eliminated and vibrations are absorbed by the elastomers.
  • Flexibility and comfort of use: The Poly V® belt, by its structure, canabsorbimpact loading thereby making the action of pedalling regular without slipping (possible drive on to a flat pulley).
  • Compact drive: The increased surface contact area enables up to 30% reduction of the pulley diameters which eases design opportunities.
  • No maintenance: Clean drive system.