Vacuum Sync Question / Confusion
So I've recently done a valve clearance check and adjustment. Clearances are now all on the loose end of the spec. I checked the throttle body sync today before final reassembly... they were really close but I wanted to get them perfect.
To my surprise, no amount of adjustment caused a change. I opened the throttle each time I made an adjustment, but nothing.
Now, I was using an old 'carb sync" tool with flickering meters; that could be part of it, but I thought I'd at least see some change.
-RPM was at 1300.
-Needles behaved identically with throttle movements.
-Engine was fully warmed up.
-Tank was off, on a table next to the bike.
-Airbox was removed.
-Air switching valve was in place and connected to electronics.
Did I miss something? Thanks in advance.
Here to learn.