Am I correct when I say that the early 80's XJ650's and XJ550's had mechanical tachometer while the same year XJ750's had electrical? Or was it just the Maxim models that had mechanical tachs? Why'd they do this? Why aren't they all the same?

My tach is electronic - it's an 83 Maxim. Will have to check the FSM. Did you want me to post it for your bike?

My tacho is also electronic. 1982 650 Maxim.