i found these handlebars that were two piece but the top piece was solid all the way across and flat...what are these and was this how they were bitd...

Are talking about galindo bars? they had a crossbar held on with 2 seatpost clamp pieces.

Sounds like most motocross bars, especially Renthals...

sounds like CW bars to me ???

CW's are welded together. A straight bar like a mountain bike bar, with a big U shape bar underneath. They were great bars back then. I have them on 2 bikes now too.