Rebuilt kit

Hello I just Bought a Kz750 1980 4 cylinders and I need to rebuild it.. the ebay seller tells me that the kit doesn’t for the 1980models ?!  I don’t know whats the model of my Kz.. on the paper its only write Kz750 thank you so much, I need to find a kit!

If your KZ is a North American model, you should be able to find the year and model in this document by looking for the frame number. You should also be able to check the engine number to insure it is within the correct range. The frame number is stamped on the steering head. That is the vertical piece of the frame immediately behind the headlight, below the speedometer and tachometer. The frame number should also be on a decal next to the stamped number.

www.kzrider.com/filebase/download/64-gen...78-kz-by-the-numbers
 

P.S. I would be very careful with such rebuild kits, as no company I am aware of ever sold any. The quality of the individual parts may not be very good. Folks I know buy the parts individually, and stick to genuine factory parts as much as possible. They are often more expensive, but you will not find higher quality. For parts that are no longer available from Kawasaki, experienced members here are willing to suggest the best alternatives. 

Are you absolutely sure it needs a full rebuild? KZ engines are surprisingly robust and will take quite a bit of abuse and neglect.

Yes my cylinders wall has some important scratches and I suspect 2 of my exhaust valves burned.. low compression and so much carbon!! Why these engine heat that much?

If your bike is a 1980 kz750 e1 or the Ltd 750 h1 from 1980 to 1982 the pistons should be the same, if you have to re bore try and stick to one size over and try and source OEM pistons and rings, like Texas says, you wont find better.

If you ebay this.

1980 80 KAWASAKI KZ750E KZ 750E 750 ENGINE CYLINDER JUGS & PISTONS

might save you a load of work and save a few bucks.

wrote:

Yes my cylinders wall has some important scratches and I suspect 2 of my exhaust valves burned.. low compression and so much carbon!! Why these engine heat that much?

These engines do not normally have heat problems. Scored cylinder walls and burned valves are signs of abuse or neglect.

Thank you very much guys, so after my full rebuilt, how often I need to make a check for the valve clearance?! 
Im planning to make a medium porting and raise the compression to 10 - 10.5/1. I already have Pods filter and stock  exhaust 4-1.. Did you have an idea how many gains I will have with it? And do you have any suggestions for jetting my Keihin cv 34mm ?! 
thank you again