Ok, guys here's one for you. I finished rebuilding all 4 carbs, put everything back together, and started it up. It ran ok. I realize I have to sync the carbs which should help. I shut it down put the air box on it, tightened up the clamps on the velocity stacks, installed air filter and cover and started it back up. It immediately rev'd to 9,000rpm. I shut it off, took off the air filter cover and filter and started it again. All was fine, idling a little high but ok. I went to put the air cover back on, without the air filter in it and it immediately started reving on it's own. I didn't even get the cover on all the way!!! As I pulled the cover away the rev's would go down and as I went to put it on and got it close to being on the rev's would rise. I could modulate the rev's by moving the cover back and forth. WTF!!!!!!!