Hi All - I used the search function and can't seem to come up with an answer. The rebuild of my 91 after a wreck in the fall is going well. I'm nearing the point of getting serious with the wiring job. I have a switch cluster from an 05, so I'll be doing some simple swaps between the old and new (wish me luck  ). The wiki has wiring diagrams for all sorts of models (http://cgi.stanford.edu/~sanjayd/gs500/Main/WiringDiagrams). Problem is, I have no idea what the labels mean. For example, what is a US EK model?

Can someone rip through that list and tell me what bikes those diagrams are for? Thanks in advance.

A EK is a 89, EL thru ET are 90-96, and EV is a 97 model.  The Wiki diagrams don't go past the 97 model year.

A 05 is a K5 model which should be the same as a 04 (K4), here is a K4 diagram:

http://www.bbburma.net/Scans/Suzuki_WiringDiagram_04.jpg

The K is a suffix that identifies the model and year.

1989= GS500EK
1990= GS500EL
1991= GS500EM
and so on, until 2001 when the suffix changed to a K followed by a number to indicate the year.
2001= K1
2002= K2
2003= K3
etc etc.

You can identify your model/year from the VIN number stamped on the steering head tube.

In the case of this example   JS1GM51A (X) (XXXXXX)   (X) = the model year and (XXXXXX) = the individual frame number.

So in your case (US EK) you are looking at a diagram for a 1989 USA model.

That's it Sledge except to note they skipped using O and Q for model year designations. 

My 89-02 Clymer manual shows the 90-02 diagrams to be the same for US/Canada so I looked over the 90-96 and the 97 diagrams linked to in the Wiki and the only difference I could see was an extra black/white wire on the 90-96 diagram that is not on the 97 diagram but goes no where (lower right corner of diagram).  And it also shows the passing light switch which is not on my 02 GS and first appeared in US on the 04 F model as far as I can recall.  Could be it was on Canadian models earlier.

Thank you!   

Do they designate California model bikes differently? I have vague memories of them adding a letter...