astrosail wrote: With respect to the runaway engine:...The real problem was actually my idle speed adjustment...Turns out I adjusted it wrong and had the idle too fast, thus the throttle butterfly valves were open too much, allowing air in, and the CV slides went crazy and caused the engine to race. Closing the throttle via the idle adjustment screw fixed my problem. Of course the pilot screw adjustment and idle speed adjustment work together at idle, so change one and adjust the other.
I owe you a debt of gratitude. Originally dismissed the comment because the bike idled fine. But having run out of ideas to fix the runaway issue, I started to mess with the idle screw.
When the engine was warm and ran away to 3000 rpm, I loosened the idle adjustment screw and the RPM feel back to idle. Rode the bike around the block and got back. Bliped the throttle and RPM stayed at 3000. Less than 1/8 turn loosening the idle adjustment screw and the RPM feel back to idle. Revved the engine several times and the RPM returned to idle. Didn't runaway.
I need to check the carbs on vacuum gauges and see if I messed up the bench sync. More accurately, see how much I messed up the carb sync!