Thanks for the info.
I was thinking more along the lines of part 121 aircraft. Had a deferrable snag the other day with a hydraulic pump. The MEL, as one of the operation requirements, refers to the "Flight with Landing Gear Down" supplement. The reason is that not enough volume of fluid is running through the system causing the gear to retract at a slower rate than normal. The MEL also cautions that a "gear disagree" warning might occur if the gear is not up and locked within 20 seconds due to the slow cycling. Consulting the performance penalties in the supplement, which are fortunately not rocket science to calculate, lead you to think that due to the gear not retracting within a required time you will not meet the obstacle clearance criteria within the segment climb if you "drop a donkey" at V1. Hence the question. Me thinks it is in the line of 20 seconds?!