I remember reading it somewhere on this forum, and this is from memory (I will try to find the link). But the large vacuum tube, some reed valves, and the small vacuum hoses comming off the 1st and 4th carb. You will need to seal the plugs on the top of the cylinders by the exhaust port. Don't listen to me tho, let me try to find where I read this.
Found it: "The other two ports have hoses that connect in a tee fitting. The other end of this fitting connects to a emissions device that is vacuum actuated. If the emissions device which looks like a brass colored cylinder about 4 inches long on most bikes, is gone, the hoses should be removed and vacuum caps placed over the vacuum ports on those carburetors. Any vacuum ports left uncapped create a major air leak that can hole a piston. I also suggest you look at the top of your valve cover if the emissions cannister is gone. there are two hoses up there that will not be connected to anything. These lead to ports in the cylinder head that are now not connected to anything. I would take the hoses off your valve cover and plug the holes in the valve cover with Permatex (black) so that air isn't sucked down into the combustion chamber through your reed valves which may or may not be in place inside the valve cover under the two covers on top the valve cover."
kzrider.com/component/option,com_joomlab...id,3/id,31398/#31398
Here is another link:
kzrider.com/component/option,com_joomlab...id,2/id,27551/#27551
Oh and Post three on this one really describes it pretty good:
kzrider.com/component/option,com_joomlab...id,2/id,55677/#55677
Post edited by: JjSwee, at: 2006/09/03 02:22