Like they say. You can lead a horse to water but you can't make it drink. While I went to Ron D. house to get the rest of my money. I ate the $50 labor from Ron A. & the $100 labor that I was going to charge for pulling & installing the carbs. Ron told me that he feels that some of the work & parts was unnecessary. I called him each time before doing a job with parts cost & he always told me to go ahead & do it. I ended up with only $200 for labor. I'm just glad it is done with. I just can't see that bike running right with out a valve adjustment. Ya it sets & idled but once you put a load on it it would die & not start again until it cooled off. what else could it be other than tight valves. Yes you are right on a major valve job in the near future on his bike. It is now for sale on Craig's List for 5 K. They know which style of valve train the ZLs have because Jeff helped me adjust my valve about 2 years ago. He asked me if the bike was running bad. I said no that I was doing it as preventative maintenance.
Jeff called me on Ron D. ZL 10. He cleaned & sinked the carbs but no valve adjustment. His compression test came back between 80 to 110 PSI. He says that is a good usable range. I thought 125 PSI was the min. He says it runs really good.
Up date on Ron D. ZL 10. He sold the bike a Month after I gave it back to him with out ever having the valves adjusted. The guy Jeff that worked on it sent me E-mails on what he did. Most of it was about bad mouthing my friend Ron A. Jeff said the carbs was way out of sync. He synced the carbs to the super tight valves. One of the carbs was cracked on top (#2) at one of the screw holes that holds the top cap on. I know for sure that Ron A. did not break it because I was present when he rebuilt the carbs. Ron D. called Ron A. and told him about it. Ron A. told Ron D. to go piss up a rope. 
. Ron D. has not talked to me since. It does not bother me one bit. Oh and Ron D. only paid me half for all the work that I did. He said it was unnecessary.
I'm just missing Ron B. & Ron C. 
Ron B. is my Wifes Brother. Ron C. died in a motorcycle accident in 1976.
Ron D. is a so called friend of mine sort of.
I'm not sure what you mean. Is that a graph for a compresson test reading. If so the kp/cm2 needs coverted to PSI. I understand cyn 1,2,3 & 4. The range looks to be 9.5 to 11.5. Anything above 125 PSI is OK but 150 PSI is ideal
https://www.fastercouplings.com/technology/conversion-tables
I'd take another reading and make sure the throttle is wide open as said before. I always tape the throttle wide open while doing a compression test. If you still get low reading adjust the valves again.
To adjust the valves is the very first step when engine is still cold and you should do it by yourself to be sure it's done well (easy to find 'how to' on the site by -Search Forums- on top).
When adjusting valves it's a good idea to make a drawing like this one in the pic. Then mark off each valve as you adjust them. That way you won't forget were you are when your wife asks you to do something or when some bone head walks up to you in your garage to try to sell you something. 
. I always make a copy of my original to use. I place an X on each valve as I go. 
Up dated Valve Adjutment Guide. I made it darker. 
Ok then i hawe to convert
