@Breso: the reason for skipping the double triangle is simply because I love the way it looks amazing IMHO. Kamil did express concerns about the rigidity. That is why, after some discussion, we choose to go with oversized non-butted tubing for the main and seat tube. Most folding bikes do feature a fairly similar design though, so I don't really expect it to be a real issue.
Below are some new pictures of the build.
@Breso: the reason for skipping the double triangle is simply because I love the way it looks amazing IMHO. Kamil did express concerns about the rigidity. That is why, after some discussion, we choose to go with oversized non-butted tubing for the main and seat tube. Most folding bikes do feature a fairly similar design though, so I don't really expect it to be a real issue.