Don't worry Bak, I would never consider you to be a "bad guy" for offering constructive criticism. When I decided to build my own bike (when I didn't know you), I relied heavily on what I read, and I think it was John Bradley that said "if you're using anything heavier than 1" 17 gauge, you're building a tractor and not a motorcycle." Of course, he was using Reynolds 531 tubing. But I reasoned that, dang, how could a little 40 hp BSA motor in a straightliner ever put as much stress on a frame as a 100 hp motor in a road race bike? After all, the records in my class were something like 111 mph (open class) and 114 mph (partially streamlined.) And I still think the design is good and the forward part of my frame is sufficient. As far as the lower motor mount goes, it is done in the typical British fashion of the bolt thru the frame. I can't lower the motor because I wouldn't be able to remove the side covers, and I don't want to raise the motor, so it goes. However, there are ways to reinforce the frame around those holes, and that is what I'll do. I probably won't change to 1-1/4" tubing because I don't have the bending dies for 1-1/4", but I think if I re-design the rear sub-frame I can prevent the same kind of failure in the future. I might even spring for a newer cast aluminum rear wheel in the hopes that it might actually be round!
Oh yes, about the top head steady. Yes I have one and it is substantial. All the crossmembers are 1" by 1/8" wall, so I believe they will survive.
Tom