ORIGINAL: hamburgler
good idea but you have to many varibales. for example what if the person consistantly is slow in starting the watch. i mean like 3/10th of a second. that is such a small amount of time and it will mess up your whole top speed thing. what about buying like a bike spedometer and calibrating is correctly. also just ask a cop. everyone knows a cop
Perhaps that is why I suggested to do it a few times before recording to allow the time keeper to get some practice on the timing. I also suggested to do it
several times in both direction and record each time. The times should be close. Lastly, I suggested you use your average time when doing the math. Sure there are some variables but there are way to minimize them. Go talk to a cop about the +/- of a radar gun. They can be 7 to 12 MPH + or -.
Besides, if the person is consistently slow in starting the watch, hopefully they are consistently slow in stopping the watch.
Oh, and your idea about the bike speedometer is great! Let me know when you hook it up to your savage. I would like to be there to watch you run next to your savage to try to read the speedometer!