bicycle dynamo to power AC outlet?

I'm thinking about scavenging a motor from a sewing machine to use as a dynamo for a bicycle. Assuming the motor is powered by ac, it will also produce ac, correct? Would it then be possible to simply wire in a regular wall outlet to the motor, and say, plug in a wallwart for charging batteries? I realize that it would be underpowered for the most part. My question is, is this just a really really stupid idea, or could this potentially work?