Cranks sometimes

I need some help, I have a 1982 kawasaki  kz750e four stroke and o have been working on this thing for almost 2yrs. Ive replaced the starter, starter clutch, solenoid, battery cleaned the carburetors religiously and checked the valve clearance. I have uni pod filters on and I have rejetted the carbs. It cranks and runs when it wants to but mostly it just turns over and over with an occasional pop out the exhaust. Just the other  day it cranked up perfectly and stayed at an idle and it sounded great. I killed it and tried starting it and again it cranked right up perfectly. The next day I was thinking I was going to be able to go for a ride but it just turns over like it always does and I can't get it to start up now, I just don't get it. I know nessiem has been giving g me advice and answering questions and I appreciate his help so much so any help that anyone could provide would be greatly appreciated. 

When it won’t fire and run have you checked to see if you have spark. Could be a ground and a loose connection in the wiring associated with the ignition circuit 

Spark plugs don´t like to many cold start cycles. They didn´t get the hot enough to reach the self cleaning temperature to burn the off the carbon bulid up and fuel left overs.
This can short cut the center elektrode ceramic insulation to ground.

Pull your spark plugs and post a photo.
Actually, try to start the bike. If the bike won't start, immediately pull the plugs and take a photo.
Only take a photo of the plugs if you can't get the bike started.

wrote:

When it won’t fire and run have you checked to see if you have spark. Could be a ground and a loose connection in the wiring associated with the ignition circuit 
 

yes sir it's got spark and the spark plug color is good. I'll take some pics of them tomorrow, I just came in from working on it since 8 this morning. I'm pretty sure it has to do with the air/fuel mixture and my throttle cable.  My cable looks like it's stretched and I have it where it's trying to fire up but just not quite 

wrote:

Pull your spark plugs and post a photo.

yes sir I'll take some pics and post them tomorrow, I'm tired lol I've been working on it since 8am this morning