the steps in question are the new IMGL steps which have a fan gear and no gearbox. The load on the delrin main gear in the motor depends on the angle of the cam. On my factory steps, the steps hit the stops just before the cam reaches 90 degrees. This will result in minimum load on the gear teeth due to the angle of the cam. Obviously the steps need to hit the stops before the gear reaches 90 degrees, otherwise the linkage will get shorter and begin to retract the steps before even hitting the stops.
The linkage length in the picture seems close to optimal, although it could be a little shorter, which would allow a little more rotation. Interestingly, when the linkage is at a perfect 90 degrees, all the load from the stops and passenger weight goes into the pivot pin and not the motor gears. Hence the problem on the older design where the pivot pin shears off!