I've seen this asked numerous times on many forums and one spot with a lot of information is tough to find. I'm 6'1, 285 and there are many coasters that I can ride and many that I cannot. I'm sure there are others like me that would find a compiled list useful. I'd really like to see folks add to this list and I can edit the first post to keep it updated. I'd like to limit this to rides that are confirmed to fit larger riders, not just rides that "look like they'll fit larger riders". I'm only going to reference rides that I've personally been on:
Six Flags Great America
100% yes, with no problems:
The Dark Knight
Demon
Whizzer
Ragin' Cajun
Little Dipper
Spacely Sprocket Rocket
Fit, but pretty snug:
Iron Wolf
Viper
NO:
V2
Batman the Ride
Note: I have not ridden Raging Bull or American Eagle in several years, ergo cannot comment on it yet.
Indiana Beach
100% yes:
Tigg'r
Galaxy
Lost Coaster of Superstition Mountain
Cornball Express
Steel Hawg
Hoosier Hurricane
note: great park for larger riders as there are very few rides that are "off limits" and all of the coasters are fine for big guys/gals
Six Flags New England
Note: I was only in this park for a few hours before I had to catch a flight
100% Yes:
Flashback
Catwoman's Whip
100% No:
Mind Eraser
Batman - The Dark Knight
Six Flags Over Georgia
100% Yes:
Mindbender
Ninja
Fit, but very tight:
Mine Train
100% No:
Batman
Georgia Cyclone
I hope others find this useful and can add to it. It would be helpful if you give a rough indication of your size. (as it doesn't help me or other like me if someone who is a "hefty 205lbs at 6'0" can fit on a ride.