Questions about my kz

So I was digging on this fine website because I have an 81 kz750 e. Bought it for cheap. It hard started but did run. Did a compression test and results were as follows
Cylinders
1.) 90 psi 2.) 90 psi 3.) 90 psi 4.) 90 psi
Well I though I saw someone say the tolerance on valves should be .10-.15. I don't have a manual I plan to get one eventually. I would just like to know if someone has one could they tell me the tolerance. And I also found two things. Same subject different answers. I'm looking for my bore size. The download copy on here says 62x54
Website says 66x54. Just wondering which is right. Figured I get it all in one post to not clutter up the forum. Any and all info is appreciated. Thank you

Take a look at the link below. It contains the Kawasaki Service Manual for the 1981 KZ750-E2 among other models. Be sure to look in it about how to check your bike's compression. You must have a fully charged battery, all spark plugs out, engine up to normal operating temperature, throttle fully open, etc. or the readings will be low. Ed

www.kzrider.com/modules/ServiceManuals/KZ750E1&H1.pdf

Manual. good version. 1980-84 KZ750-4. 1983-85 ZX750. 750turbo.com --- Index . occasionally unavailable.
yellow/gold cover w color wiring diagrams. get the one listed as ->> GPz750 Base Manual.pdf. good scans.
The one that says full english is a cruddy, photo-copied version.

Wiring diagrams. mbsween. bike-night. KZ750L3 . Scroll down & click "The Bible" link. also has the poorly scanned pdf manual.
Note: some of the wiring diagrams are mislabeled in the links: the 1981 Ltd is an H2, the 82 is an H3, & the 83 is an H4.
....

Ok thank you for that. But now my quiestion is even with the low readings on compression there's no power at all. Like as soon as there's even a little clutch grab. Engine bogs down and dies. And after running for 30 seconds it pops through the carbs. Could that be that I have a bad vacuum on my carbs? I really wanna get this bike running. My valves are all at .08 surprisingly and that's well in spec. So that ruled out my first thought. Bore is 65mm which leads me to believe it's never been bored according to this and a few other websites. So I'm trying to figure out if I'm gonna have to shell out 500$ for new parts are if I'm going to just have my carbs synced.

For a got compression test your engine has to be warm up before.
Pull all spark plugs and rev the engine with full throttle and a full charged battery..

Yes I saw that part thank you

Sounds like you need some $70 carb holders.
Steve

I'm not seeing how that effects me at this point. Please elaborate for me.

Do you have the stock air box and filter installed? Ed

650ed wrote: Do you have the stock air box and filter installed? Ed

Yes bike is all original with expetions of boots and paint

The intakes may be leaking.
Steve

SWest wrote: The intakes may be leaking.
Steve

I guess that makes sense. I'm gonna check a few other things first get the cheaper stuff checked