I bought two of these so you can hold one nut while you adjust the other:
https://www.mikesxs.net/yamaha-xs650-hook-wrench-for-40-45mm.html?gad_source=1&gclid=Cj0KCQjw0MexBhD3ARIsAEI3WHL0n6ag0ey8vq0xbS6zf8s2-85o9MOJHt-kIOSarZIWlINp2Gf2KFMaAmOnEALw_wcB
I use a thick 3/4" wide chisel to get the bearing off of the triple tree shaft. It acts as a wedge.
For the races in the steering stem, I try to pound them out with a drift and chisels and misc tools. If they don't oblige, I cut them with a Dremel cutting wheel.....but it looks like you got...
Just as Firemedic was alluding....
As you open the butterfly valve (throttle), the air flow increases and it is supposed to draw more fuel to go with the faster air flow....yet it dies.
I would drain each fuel bowl and see if they have the right amount of fuel and if the fuel is clean. If...
My wife has cataract surgury upcoming this summer for both of her eyes, and she is terrified.
Your story comes at the just the right time to calm her as best as possible.
Thanks for sharing your experience Bill.