Originally Posted by
Onegun
It's the downward flex that I was concerned about. You want to be able to cinch the tie-downs sufficiently. Not like you were compressing the suspension to strap down a motorcycle, mind you, but enough to make the bike feel like part of the vehicle. If that rear tray is too weak, it may bend. But you're the one looking at the setup, and you have to make that call.
If you're not comfortable with the single tray by itself, get a 4' strip of flat iron from the hardware store, paint it black and bolt it to the bottom of that section. Or replace the whole deal with a piece of heavier channel aluminum. Or figure out how to shift the mounting of the whole rack forward, etc.
Paraphrasing what TandemGeek said, the price of under-engineering your homemade rack is FAR greater than over-engineering it.
That's what I was thinking. I guess I'll swing by my local home depot and see what kind of metal bar I can find to add rigidity. The rack really isn't for long distance driving. More for hauling the bike around town to local trailheads and that kind of thing. And for emergencies. Unfortunately I live in a location that requires some short stretches of fairly aggressive busy highway riding to get out of our neighborhood. Which is fine for me when I'm out on a ride by myself. But not so great when I'm out for a family ride with the wife and 3 girls.