hi
firstly let me introduce myself, i am 54 and have a 1989 xj900 which to all intents and purpurses is the same as yours
while i was looking for an exhaust, the american company market one for yhe xj650/750/900 which they say will fit all, at the moment i am looking at an exhaust for the 650/750 to which the silencers look identcle to the 900 ones, i am going to take a chance on this as i need silencers as well, al;so motad do a 4-1 for this bike
hope this helps
andy