Howdy. My 81 KZ650-CSR has the same frame as the 750H Ltd >> 750E mufflers were a direct swap. The Ltd H & & 750E frames appear to be very similar & are identical in some respects. The E has the same side covers & muffler stays as the CSR & LTD. From comparing photos the major differences are the steering head angle & rear end >> the Ltd has more rake & the E has extra bracketing at the rear for attaching the rear cowling or ducktail which the Ltd does not have.
Seat & fuel tank. comparing frame photos, the 750E seat may be a direct fit >> the hinges & stuff appear to be in the same locations & the frames seem to be shaped the same where the seat fits. They also have the same method of attachment for the fuel tank >> the E tank is purported to be a direct fit, but the Ltd tripe tree will bang against it. The fix would be to install the 750E front end >> the 750E triple is angled forward to accommodate the larger tank. I bet the E triple tree is a direct swap. guessing.
Swing arm. From the diagrams at Partzilla the 750E & Ltd have the same swing arm sleeve & shaft and same Rr axle, so you can probably swap swing arms. I'd guess you could use your swing arm with the E rear wheel >> the Ltd swing arm is probably wider. I'm not sure if there would be disk alignment or wheel clearance issues. From doing the wheel math the E wheel/tire is about 16mm larger in diameter than the Ltd.
Carburetors. I don't know what's best, but you can probably use the carbs from just about any 750-4.
KZR topic >> Retroactive KZ750E Project by Nessim
.... lots of good photos, including frame pics.
EB >> KZ750H Ltd frame.
. or use you own frame for reference.
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