the one pipe fit in another is just for transport. upon arriving to said country via airlines, then take out the inner pipe and use on frame. I was thinking the stronger/wider pipe would be used for the critical frame pieces, and smaller diameter could be used on like the seatbars and cooler holder bar - you know. I would use bolts for the fittings just like they do now.

so the goal is to make this small package for keeping the frame in size/wieght limits of checked baggage. tough problem.