Won't START!!!!

You still have an air leak. I had this recently on a KZ750E, cured by using new boots and Castrol red rubber grease. The grease helps the carbs to sit fully home in the boots. Also definitely check the pilots.

It does seem like there is a significantly lean mixtire on at least one cylinder. It also is important to insure proper valve lash. You will not be able to fine tune the carbs if one or more of the valves is out of spec. It is one of those maintenance items (like changing fork oil) that is frequently overlooked and can really affect the bike's performance.

Hey All, WHAT A MIND TWEAK!!!! I took the valve cover off, rotated the crankshaft to the "T" mark with cyl. 1 & 4 at TDC, and the camshaft sprockets looked like they were both off a tooth. So I removed the camshaft caps, moved the cam chain to the new position, and rotated the crank several times to confirm the new position. Also, I checked the valve shim clearances and everything is within spec.

Well, that didn't do SQUAT! I still have the EXACT same problem. I am really getting discouraged with this. I mean, if I can't reassemble the top end of a a simple 1970s bike, my skills must be very lacking.

So far the carb has been cleaned within an inch of it's life AND had compressed air blown through all the jets and passages to confirm that they are open, and the valves/camshaft position/etc. have all been checked. I guess the only thing left is the coils? Anyone know of a way to measure the coils with a multimeter??? Thanks in advance!

Hey All,
An update: looks like it's all about the carbs. After replacing the head (again) and installing new exhaust, Cyl. 1 & 2 still won't idle - cold exhaust pipes. Gonna start a new thread and see what ya'll think, thanks in advance!

Looks like fuel is not going in to #1 & #2 cylinders. Probably carburetor boots for those cylinders are either damaged or not on tight enough and fuel is not being sucked into the cylinder, or the carburetors that feed these cylinders still need to have cleaning done to them.