I was at the main Trenton DMV office renewing a registration and I asked the clerk about the legality of a "bicycle engine kit I purchased on eBay". The clerk didn't know, and called in the supervisor who told me that: If the motorized bicycle travels under 25 mph, it is up to your local municipality to regulate such vehicles. If it goes over 25 mph, you'll need it register and insure it as a motorcycle, and have a motorcycle license. No mention of "moped" here, and I did make it clear that the pedals are still functional. So I called my local police dept. and asked them if there were any laws regulating motorized bicycles, and he said that there were none. Truth is, I have gotten pulled over plenty of times on my small street legal Trail Cub motorcycle and never once on my motorized bike. I keep my speeds at 15-20mph on the bike so I don't attract any unwanted attention. I don't get hassled with the motorcycle anymore because they know that it is street legal and not someone riding a dirt bike on the street.