KOPS, or Knee Over Pedal Spindle, is a traditional technique employed by some bike fitters to find the saddle position and determine the saddle setback.
What is KOPS
According to KOPS, when the crank arm is at 90 degrees on the downstroke, a vertical line from the tibial tubercle (the bony protrusion below the knee cap) should intersect the centre of the pedal spindle. This measurement is taken when the rider is not pedalling. In recent years, most bike fitters tend to move this point a little forward – usually 10 mm.
The source of KOPS is largely unknown, but an early bike fitting paper by CONI (the Italian National Olympic Committee) in the early 1970s references it.
A Controversial Theory
There is not a concrete justification or biomechanical logic for utilizing KOPS to set saddle fore/aft, yet experienced fitters suggest it in their books.
Conversely, KOPS has been heavily criticized by other experienced fitters, mainly because of two factors. First, because Kops method does not consider the cyclist’s flexibility. This is often translated into a higher saddle position. Second, Kops is only efficient for some cycling speciality. For example, this method doesn’t provide the best solution for fixing the saddle for a time trial race.
So why should I find the saddle position with the KOPS method?
KOPS is simple to learn, understand and apply, which may explain its common use. It can be a helpful starting point or suggestion rather than being used independently since bike fitting should not be a set of straightforward rules and equations. And for classic cycling specialities – mainly road but also gravel – it works on most cyclists. So if you have an average elasticity, Kops provides a good position on the saddle. Of course, the bike fitting should be complete, and you can’t fix your position with just one measure, but without a bike fitting session, the Kops method helps a lot to find the saddle position.