I LIVE IN the OPHIR AREA IN THE SUMMER
You've already seen some good advice from other folks regarding this area. So take this for what it's worth, I know the area fairly well and would like to offer my two cents for what it's worth.
Most of my neighbors ride 250cc and smaller bikes over these passes for regular day or weekend rides. Some of them are really, really, REALLY good riders, I can't stress that enough. Having said that, we do know a couple who have done Black Bear, Cinnimon, Engineer, Ophir and others passes TWO UP on a BMW R90S. They are still married, so I guess love conquers all (they were 30+ years younger when they did these rides and she did some walking and pushing.).
My opinion is that you might do these passes on that big bike with limited experience but it would NOT be something to take lightly and would be more in line with going to prison, maybe evan a mexican prison.
There is a world of great riding in CO and UT, and other western states that you would enjoy on a big bike and at the end be able to go home to enjoy family and friends.
Ride Safe, Live Long.
The good you do is good for you!