Difference between the 700 and 750 engine

I have a '85 700N that has bad valves and if I can’t get the head rebuild I need either a new engine or a new head. I have access to a parts bike, a XJ750 not sure of the year, I’m wondering if the heads are interchangeable? Are the only difference between the two bikes the jugs and piston size? Are the other parts interchangeable? The 750 has been sitting out in the weather for a while with nothing covering the intake or exhaust and I don’t know what kind of condition it is in inside. My 700 engine I tore apart today and is in great shape other than the valves, so if I can just get a new head I’ll be good to go I just need to know if other sizes than the 700 will work for it. Any help would be appreciated.

 

THe 700 was a tariff bike I think most of them were sleeved, but I don't have the info in front of me right now.

 

yeah thats what i though I read, that they just down sized the bore on the 750 to make the 700 so i was hoping everything else would be the same.

 

I don't know about the aircooled versions, but I know that for the Maxim-X, which came in both a 700 and 750 model, that the 700 merely had a shorter stroke.