Domestic Terrorists?

[Ragtaghorde]

Young imagineer who can make just about anything works for tech zillionaire in Colorado. Killed his father as an abused juvenile but has amnesia about whole incident. He dreams about a Civil War soldier who has “seen the elephant”. Foils secessionists who want to break away from USA. Has bicycle he has souped up with electric boost but just looks like ordinary bike. In love with army general’s archeologist daughter. Set slightly in the future.

Published prior to 1990. Maybe early 80s? YA or maybe older kids.was a library book.