Jkson

You are welcome! Few days ago I repeated official and mine way. Just to be sure, one more time. It is definitely smoother and bike has more torque on low rpm, with #3 and 4# more vacuum.

Yeah, most of us read it as dropped down, less vacuum. And it is very common issue with VFR 800 any generations - hesitations, surging, jerky on small throttle opening. Many, many topics about it. When vacuum is ajusted lower or even flat, 3rd and 4th cylinders have lean mixture. Its a reason why PAIR blocking helps a bit. Because PAIR allow to intake a bit fresh air into cylinders from exhaust port. When you block it, you make your mixture reacher on idle and low revs.

Hi there! I know, its a bit strange to find incorrect procedure in workshop manual 22 years later. But no one did it, and I want to share my story now. According to 5th gen manual, 3rd cylinder vacuum pressure should be dropped to 20mm compare to 1st. Most of us read it as dropped DOWN, and translated manuals have it mentioned as LESS vacuum for 3rd and 4th. When I got my bike, it had flat sync for all cylinders. I did full maintenance some time later, through workshop manual, include starter valves synchronization. In very first day after, I noticed some surging when low