11.   Some electric bikes employ bolt-on engines with a friction wheel that rotates against the rear tire to drive the wheel.

12.   The high prices of electric bikes are most likely another deterrent.

13.   The manufacturers have contributed to the confusion in that the two types of electric bikes now being produced are quite different from each other.

14.   The number of companies selling electric bikes has blossomed in recent years, particularly in Asia, where bicycles are a primary form of transportation.

15.   McGreen was tinkering with a working model for an electric bike.

16.   There are other electric bikes out there, but the company says only ZAP!

17.   Until now, an electric bike has fallen under the jurisdiction of the National Highway Traffic Safety Commission.