TOPIC:

I'm sure this is the world's dumbest question, but how do you open the stock seat on this bike?  This '82 is as bone stock as they come.  I have both original keys.  The bike has two of what look and act like helmet locks on each side under the seat, but as far as I can tell they only operate the helmet loop locks and don't release the seat (like my 1980 Yamaha XS650 does).  I have looked under and around for a release and do not see one.  Maybe this is a friction-fit seat, but I'm hesitant to just yank on it and risk breaking it as this bike is so original (yet needs a full resto). 

Thanks for helping a GPZ noob figure my teenage dream bike out.  I have wanted one of these bikes since I was 16 and about 10 years ago found this one on CL for$ 600 bucks(haha that does not happen anymore) but its resurrection has had to wait until our massive house build was finished(soon to be done).  I'm now getting itchy to get this old girl running and go riding with my son.  

Thanks again.

It's been a long time, but I think it's the same key hole/lock. Just turn the key the other way. Also, feel under the seat for a latch or hook... maybe?

I believe the latch on that model is behind the seat on the tail cowl.

You can see it in this picture under the grab rail.

 

Oh wow.  I think you are right.  Mine has a small black spot there that I did not pay much attention to.  That must be a sliding cover or a rubber cover.  I'll check when I get home today.  I sort of looked at that and pushed it with my finger and it did nothing so I thought it was just a cover for a screw for the tail panel.  Seeing that pic I'm sure you are correct.  The funny thing is, years ago when I first got the bike, I had taken the carbs off to clean them and I remember having access to the air box so I had to have removed the seat at some point.  Haha. Thank you!

As TexasKZ indicates. In the diagram note the seat lock cover & location of the seat latch.
www.partzilla.com/catalog/kawasaki/motor...0-h1/seat-seat-cover

note the orientation of seat lock. 27016A in the diagram drawing.
www.partzilla.com/catalog/kawasaki/motor...tch-locks-reflectors

I found pictures of an '81 and you are correct that is where the release is, but for the '82 they changed it I guess.  I always thought the '81 and '82 were very similar(despite the unitrak), but the more I look the more siginificant the detail changes there are between the two years.

Confirmed. Thank you.

 

1982=1983 Both have it in the top of tail behind the grab bar.  

Since you have an early '81 and an '83, I have one more question.  The crankcase top plug (right side cover) does not have a dipstick attached to it.  How does one check the oil level on this motor?  I have yet to find a way.  There seems to be a sight glass at the forward bottom of that side cover.  I've not really climbed all over this bike and it is stashed in a dark corner so it's sort of hard to get a good look at it.

For reference here is a link to my '82 GPZ550   It appears to be all there even down to the top bolts for the forks still having their rubber caps(although they appear to be barely hanging on).  I do think this bike has had a paint job or maybe part of it has.  The side covers and faring has the clear coat failing, but the tank and the front fender do not.  Odd.  There is some cracking of the paint on the tank near the seat that looks like Bondo underneath is failing.  While the paint on the rest of the tank look good...ish, I do think some work has been done to this bike's paint.  The rubber buttons on the cluster that reset the odo and change the tach to a voltage meter are rotted away.  Is anyone making those?  Everything else seems to be there,but sadly the bike was left outside(abet under tarps) for many years by the PO.  BTW there is a pic of two wires under the seat.  They have different ends and do not seem to connect to anything or each other.  Do you know what they are for?  Different market accessories?   

Lastly, does that look like the correct seat cover for an '82?  Is it the '81 that has a design on the side of the seat?  Maybe this is a repop cover?  It's hard to tell. 
 

The sight glass is how you see the oil level. The bike needs to be on the center stand for a minute or so to let the oil settle. There are two casting marks on each side. The oil level should be between them.

See the picture on page 24.

www.kzrider.com/modules/ServiceManuals/Kz400500550_79to83.pdf

There is a wiring diagram in the manual. It is probably near the back in the 1982 supplement.

You can find some of the differences between the different years. Page 70, I think

www.kzrider.com/modules/ServiceManuals/M...nition_1982-1985.pdf
 

Really appreciate the info.  I scored a pretty good factory manual for not much, but have yet to really look at it.  I take it, there is not a separate manual for the GPZs and just the supplemental sections at the back?  I found some tools in the box, but only two of the original wrenches.  I'd like to get the correct one with the correct bag.

Kawasaki included he GPz with the other models in the fsm. The supplements at the back are for updates made in subsequent years, so anything that changed on any of the models from 1981 to1982 will be dealt with in the 1982 supplement.
This can make finding the most up to date info a little tedious at times, but keep in mind that these manuals were created before digital printing existed, so adding a few pages at the end each year was far more cost effective than redoing the entire manual.

I have a document showing the various changes in the factory tools over the years, which may help you in your search. It is buried somewhere in a dark corner of my computer, so it may take some time to find it.