Efficiency is the tire's capacity to deliver the energy supplied by the cyclist in riding conditions.
Efficiency is expressed by the following formula: (energy delivered) / (energy supplied) = Efficiency.
As this formula always gives a result of less than 1, efficiency is therefore always expressed as a value between 0.00 and 0.99.
For the tire part, efficiency depends on:
- the nature of the rubber compound (presence of silica, ...)
- the tread pattern
- the density and construction of the fabrics (TPI, or number of threads per inch)
- the architecture of the tire, the reinforcements, …
- the quality of the inner tubes used (MICHELIN :Latex>UltraLight>AirStop>Protek)
- the tire size (23>20>...)
- the inflation pressure (8>7>6bars ...)
- the tyre's rolling resistance
There are other external factors affecting efficiency:
- the nature of the road surface
- wheels and bearings