Joined: Apr 2010
From: San Jose, CA
I Ride: 2015 ZX10R, 2014 Ninja 1000, 2012 Z1000, 2003 Z1000, 99 ZX9R
Good luck my friend. I have been trying to find this for a couple years. I have compared engine serial numbers across years of ZX7s and they are all over the place. I have asked a couple Kawi dealers and some of the race builders. No answers.
91-93 motors all take the same gaskets and many of the parts are common. The biggest difference is the compression is lower and cams are smaller on the J model (91-92 non-R model).
They changed the cases in 94-95 to be a common casting with the ZX9R, although the bearing sizes from the 7 to the 9 are different. So all is common in the motor on 94-95 except the transmission is different on the R model. It is easy to spot a 94-95 case as there are two "donuts" on the front of the cases used as motor mounts on the ZX9R chassis. The two donuts are on the front of the motor, just above the parting line of the cases.
96+ parts are all the same except the R model has different cases with extra webbing and a different transmission.