what kind of lock are you using! Go to the store and buy 2-3 feet of the thickest chain they have and wrap it in fabric/rubber. Chain it to your bike with a padlock, thicker than the chain. Make it easier to cut through the city's bike rack then your chain! The only comparable lock to this one costs over $100. Just go buy thick chain for cheap! don't get "U" locks, they can be opened with a car jack or just a hammer. don't get "cable" locks, those are the worst. If they cant just cut through them with heavy duty snips, they can pry the ends of the cable out of the crimping on the end with 2 long metal bars or vice grips. I use a super small cable lock to lock my seat to my frame, that's all I trust it to do. The only thing they can do to a chain and lock is cut it or pick it! This is too much work for most thieves!!! Never buy any bike lock you wouldn't trust to hold your weight if someone threw your off a cliff! nice instructable and nice bike. I always like a custom paint job, it not only deters thieves, it makes your bike feel more like your own.