Go karting is so much fun. Gollum, the best time to be by yourself is probably on a weekday. That's what I used to do in order to find the best racing line on the track.
Currently, I go to a local indoor track where they run those 6.5hp Sodikarts. The track is fairly close to 1/4mile in length. I used to hold the track record of 26.49, been top of the month 4 times in a row, champion of their last league.
The most fun I have is racing with a full crowd of regular customers. I love their expression when they see that my fastest lap is like 3 seconds faster than theirs.
Sean