Antinos said:
It appears that Baco's seats are on pillars, so to speak, but Wild Eagle's are mounted more behind and closer overall to the seat's centroid.
Don't take this as law of the land though, as I haven't studied mechanical vibrations yet and I'm only halfway through dynamics.
You're going to have to do some pretty advanced vibration classes before you start looking at stuff like this. Most of those classes are focused on linkage vibration/damping.
However, you're basically right.
I think (I don't know, I don't have the inclination to actually figure this out) that one of the reasons is exactly as you said. If you were to measure the absolute distance from the centre of the track to the centre of mass of the two riders, the number for Baco would be much higher. As you say, the seats are mounted above those bars instead of level with them, meaning the seats are essentially further from the centre of the track (assumed to be the centre of the vibrations). As distance increases, the effects of vibrations increase etc (depending on damping in the beam). Which leads onto the fact that I also suspect the kink in the bar has something to do with it. Joins tend to improve damping (depending on how they're joined) as they absorb energy, so there could be something in the actual geometry of the connecting bar too. Baco's is straight, whereas the B&M ones have that kink in them.
ALL of that being said, I think it's also important not to forget that Intamin coasters (in my experience) aren't as smooth as B&M coasters. Even when they're new. I rode Rita in the opening season, and Hulk 7 years after it opened (both 2006) and Rita wasn't as smooth. I suspect something in the wheel assembly design, track tolerances etc that comes into play and is simply exacerbated in these wide trains. You can feel the B&M ones bouncing slightly, so...
Finally, let's not forget that Baco is a little bit more intense than any of these B&M coasters. Don't get me wrong, I think Baco (besides the launch) is ****, BUT it does launch to 83mph and
then drop into a ditch. Baco is seriously fast. Gatekeeper is only 67mph (the fastest of the B&M models, except maybe the one in Asia, but RCDB didn't have the stats for that one yet), so in Intamin's defence, I'd like to see what would happen if one of these B&M trains hit a corner a 90mph. I bet they'd be pretty bouncy too.