Sorry to keep coming to you guys with problems but I really can figure this one out, it is driving me MAD! I can't figure it out! Here is the story, I replaced the cam chain and got the valve timing all set as well as the valve lash which I double checked and put the bike back together. After I got it all back together I synced the carbs (using the bunch of interconnected tubes with the oil in them, make them for like 5 bucks.) But they are like impossible to sync. After they are all even I will restart the bike and they are all off again. It also surges at 6000rpms. I checked the plugs and they are white. They are all getting plenty of gas and the carbs have been totally cleaned and the floats are set. I checked and found the manifolds were leaking so I replace them all and tighten them down good. I re-sync to find the #4 carb has very little vacuum even with it fully adjusted. I take the carbs out again soak the jets in cleaner blow them out good, and spray and blow with air every passage way in the carbs and replace all the vacuum tubes. Still the #4 is the same! I did a compression test and it is also good. Where else could the vacuum leak be? I need help guys! This is killing me. Thanks, it felt good to rant.

 

ya sure the vac tube is sealed tight on # 4 ?? when you are holding the rig ....no kinks

 

Yeah it's tight, plus the #4 plug is lean, before I hook up the syncronizer.

 

So where else could there be a vacuum leak besides the lines, diaphragm, and manifold?

 

I am thinking the others may be too rich. Would a rich mixture make more vacuum?

 

I also noticed that it hisses when the choke is in.