For teaching my small children to ride, I took the pedals off and set the seat low so they could push themselves along with their feet on the ground. For your parking lot trials set your seat low so you can easily put your feet down while you get the hang of steering and braking. You dont have to think about leaning into the turn. If you want to turn to the right, give the right handlebar a sharp push - that will make the bike lean over to the right and the turn will follow. The sharper the push the more abrubtly you will go into the turn - this type of emergency steering is an essential manoeuvre to learn, it will be a lifesaver when cars do a right turn while they are passing you. Dont ride on the sidewalk until you are sure of your steering, because you dont want to fall off the sidewalk into the road, but dont worry about the legality - your primary concern is your safety and enjoyment. I am sure any cop will be sympathetic if you explain you predicament. Keep you speed down on the sidewalk because cars coming out of driveways are looking for people coming at pedestrian speed.

http://www.parktool.com/repair_help/index.shtml

http://www.sheldonbrown.com

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