77 KZ 650 rebuild - want to increase cc, how much?

I have a 77 KZ 650. I am currently in the process of stripping it down to rebuild it. I want to bore it out and go bigger. Does anyone know how far I can go? The block is massive, way bigger than it needs to be for those pistons. I had heard it's the same block as the large KZ's use. Does anyone know if that is true? If so, can't I bore it out to the larger engine size and replace the critical bits?

I'm also looking for some horsepower increases for my rebuild if anyone has some tips.

Easyest way is to install a 1980 kz 750e engine and bore it out to 810. the 750 is a direct fit no modifications need to be done to make it fit.

I guess i want to use the pieces I already have. I'd like to modify those. THat would be ideal for me.

well you could bore out the stock 650 jugs and install a 710 kit or use a 750 jug and bore out the upper case to accept them.

A KZ750E uses a completely different charging system than a 77 KZ650 so if you did go the KZ750 routt the reg/rect ect of the KZ750 would have to be swapped over as well, or the 77 KZ650 stator/stator cover/rotor would have to be swapped over to the 750 cases. One of my 650s has stock size GPZ750 Kawasaki pistons in it and it runs real good. That's 740cc I think. I think that's the limit.