Thank for all your help, managed to find info i needed, if anyone is intrested heres the details i obtained:-
XJ750J
XJ750K
XJ750MK theses 3 are classed as a MAXIM and all have the same frame/part No 22R-21110-00-98
XJ750RH
XJ750RJ
XJ750RK these 3 are classed as SECA and have frame/part No 5G2-21110-10-33
the frames are both Very similar as they have same engines but mountings for seats/side panals are different.
again thx for help Dan