kz700 to 750 conversion or not?

I've been looking at a couple of old 1984 kz700's and one have rather poor compression (to put it mildly) but looks amazing. Would it be a straight swap to a 750 cylinder or do I need to get it fixed? Finding a good one won't be easy around here, and I'm not in the US, so getting the cylinders fixed and ordering new pistons would cost an arm and a leg as far as I know.

Hmmm.

Same block, same bore.
The 700 designation came about back in the "80s
because harley was whining to the feds and got a tarriff on
bikes 750 and larger. The 700 has 738cc and a 66mm bore
just like a 750. Same engine just a work around the 750
designation. New old stock pistons or a wiseco kit are your
options.

.

A lot of old bikes die a horrible death brought on by the lack of valve adjustment. The valve clearance goes away with mileage and eventually the valves hang open destroying compression, and sometimes causing the valves to burn in the process. The fix may be easier than you think.

I'm planning on looking closer on the engine this winter and I'll be looking at the valves too. Thanks for the replies.

Hello, the above reply about block being the same is not correct. Funky story, 700's were made to avoid 750 tariff's. The 700 is a 700cc. The bore is 64mm the 750 is 66mm, My Manual says so. I have 35 years exp. with a Moriwaki 650 and a Original ATP Turbo KZ-750, (One of a kind). I have collection of lo mile 750+650 parts, all interchange, but different ways on cams. I have a couple of set ups that could work. I have a RC-Engineering 717cc Hi compression set, 717 turbo Lo compression, Stock KZ750-GPZ -5 SETS. I can give you any help to go regular or VERY Fast, My bike spins 13.5k+and comes out of third about 140mph. I have mess with a lot of combo's with this thing, IT has been bullet proof with GPZ bearings and Moriwaki valve springs and lifters. More info than needed maybe, but the 700 could be a great platform. I can tell you what parts are cheapest to get. the kz's are cheap donors 4 that bike. pic is a box of pistons and stuff, I have 7 or 8 boxes of goodies.

It is actually correct, just a misunderstanding between you guys. What he answered was that the 750 is exactly the same as the 700 except the cylinder - and that is a direct fit.

I don't think I'll try to get any extra HP out of it. I'll see how it looks and maybe fix valves and cylinder, etc in winter if needed. Any help will be appreciated but I'm a bit too far away for parts I think.