Crown Timing
As in depth as Crownring is, aside from T-value, there are only two dynamics to effect the system: crown size, and crown timing. Crown size is covered under the Crownring link on the left panel.
Timing refers to the pedal position when the crown is at peak engagement. Peak is when the crown is perpendicular to the chain tension. On an upright bike that would be pointing straight up. Effective timing is during the second half of the stroke, when your leg straightens and has the power to manage the rise in radius. That is crownring in a nutshell, raising the radius when strength increases.
Timing can be advanced or delayed. It can even be stretched as is explaind under the Stretch link on the left panel. Timing is not so much about the crown peak or how long it lasts as it is about incline and decline.
Incline is when the crown is rising to its peak. There are a few degrees of adjustment as it transitions from low radius. This rise works with leverage decline. As leverage lessens the ratio increases. The incline also increases ratio. Together they create a rapid rise in ratio just as leg strength is experiencing its most rapid increase.
The incline can be timed differently. Sooner is less leg strength but more leverage; power over speed. Later is more leg strength but less leverage; speed over power. Although, there is room between to average them both.
The peak is short lived unless it is stretched. Stretch will alter timing. Regardless of peak duration the phase following peak is decline.
Of all the phases of the crown, decline is the most important. It works with leverage opposite what the incline does. Rather than increasing ratio it decreases ratio, but leverage is also decreasing. By declining ratio as leverage increases ratio we combine them both into a constant. Ratio maintains its highest margin well into the Dead Zone. Time it late and ratio rises, increasing the Dead Zone and cutting off power input. Time it early and ratio meets low radius and sacrifices speed.
Timing is about performance. It combines radius with leg strength. You can time for power or speed. Experience is the only barometer.
Text updated September 27, 2025
