Well, there were two main variations. In the pilot, the motorcycle was based on the 1983 Honda XL500 trailbike. The main bikes used in the series' run were based upon the 1984 Honda XR 500s. And, stunt bikes were based upon Honda CR250s. The Cars of the Stars Motor Museum has the only surviving bike. I'm sure if you contacted them, they'd be willing to share information and parts that they used in their restoration. Here's their website.
http://www.carsofthestars.com/cots.html
Hope this helps