Bikes get stolen in St. Paul all the time. It goes without saying that they need to be locked up when they are not in use. The best practice is to keep your bike locked in a shed or garage or inside your house and lock the bike too.
I keep mine in a locked shed and the bike itself is locked to a beam in the shed. When I use my bike to run errands I try to lock it to a bike rack if there is one. I also make sure the bike is locked in a location where I can see it or where there is a fair amount of foot and car traffic.
Bikes are high theft items. If your bike does get stolen make a police report. You will never get the bike back but the report shows that it was stolen and may be useful for collecting insurance.
