Getting 1981 KZ750E with low miles roadworthy...

Found this silver one with 20K miles recently. Owner said it sat in garage for 11 years but ran well prior to being parked.

So far I've gotten a battery for it and pulled the carbs yesterday. They were pretty gummed up, visually not too bad but the slides were stuck. Had to push pretty hard to slide them out but got 'em.

Electrically all seems to work except turn signals come on but don't flash (hazards do flash). Common issue it seems. New flasher didn't help but I got the old style one. (Edit: Didn't realize there are two flashers. The turn signal flasher was bad so that's fixed.)

Pulled the plugs and sprayed fogging oil down cylinders. Oil looks clean through the window so going to try to spin the engine today but not start it yet.

I'll load up more pictures as I go along. This shot is in it's prior home:
 

Here it is after I got it home and gave it a wash:

So tried to see if starter would turn the engine with the plugs out. Nothing when I pull clutch in neutral and press start button. No click, nothing.

I then put it in gear and turned the rear wheel by hand. Was pretty hard to turn, had to grab with two hands and put my shoulder into it but was able to spin it a few times. Not sure if it should have been that hard to turn with the plugs out.

Going to study up on what to do next but maybe someone here can give advice on some basic troubleshooting steps...

Edit: Fuses good. Also, stupid me didn't realize there are two flashers. I only changed the hazard at first; the turn signal flasher beside it was bad so that's fixed.

Edit #2: So checked input to starter solenoid. Key on, neutral, clutch in. Push starter button, no voltage at input to solenoid. Clutch switch was easy to check, couple barrel splices along the frame near it. It's good. Think I need to figure out how to check ignition switch and starter button.

Franklin, your 750 is very cool. Nice purchase! 
Wiring, on a bike, car, boat... hell even your house or shop, is the adult version of "connect the dots". 
Start at the beginning & connect all the dots, or prove the dots are connected. Battery has voltage? check. Voltage gets to ignition switch? check. Does it get out of the switch? check. Continue until you find the offending party & go riding! 

Well, I believe the offending party is the ignition switch. Used that blocky ignition switch drawing from the wiring diagram and found brown wire did not connect to yellow wire as it should. Neutral indicator that runs through engine stop/run switch. Also, red to blue was flaky, has to do with taillight. I could wiggle key and get it to read a couple of ohms but mostly stayed open. (I already had hit the switch with De-oxit and that didn't help.)

I'll also note it was easy to check start push button. I had the right handlebar control apart already because of pulling carbs. I could get meter leads in the back and check the button.

Any suggestions for where to get a good replacement ignition switch? I've seen a lot out there so advice would help me narrow it down.

Edit: I got impatient and pulled the trigger on one listed for '81 KZ750E...

Looks like it's in pretty good shape!  There are a few of us on here with this same year/model bike.  

Very nice looking, considering 11 years in hibernation.  You should be able to find most parts on Z1 Enterprises.

Great looking bike Franklin.

I got an Emgo ignition switch from either Fortnine or Z1Enterprises - cant remember which  - 5 or 10 years ago. Pretty much plug and play except that the connector block didnt have a catch but a zip tie fixed that.  Late now but just make sure the steering lock mechanism is oriented correctly..

 

So I got new tires already. It has Dunlops on it that have tread but must be pretty old.

I found I could get Shinkos pretty cheap and Dunlops for a little more. Didn't really like the look of the tread pattern on either of them. I figure from my past experience on a KZ750 it doesn't need super sticky sportbike tires. The suspension isn't really up to it and the pegs will hit the ground before pushing a really good tire. So I paid attention more to the look of the tires.

Back in the '80s raised white letters were a thing for a while. I remember getting a white paint pen and coloring the letters on my FJ1100 long ago. So with that in mind I found a Bridgestone Spitfire front tire with the lettering. A little odd the letters face outward instead of inward but that's OK. It's basically a Harley front tire but advertised as good for sporty riding.

I couldn't find a matching Spitfire in the right size for the rear so settled for a different Bridgestone. Got a 120/80 Battlax. There was a 120/90 available but thought less sidewall would look better. I got a paint pen and colored in some of the lettering to match the front. (In the photo I wiped some of the protective blue stuff off the front tire to see how it looks.)

The next time you need tires, you might want to consider Avon. They make excellent tires in the appropriate sizes.

www.avontyres.com/en-us/tyres/roadrider-...1989&engine_spec=733

So does Pirelli

www.pirelli.com/tires/en-us/motorcycle/c...668&segment=standard

I like the Bridgestone Spitfires front and rear on my 750. The front one I bought last year had that raised white lettering. A black sharpie fixed that   

I had considered the Avons but they were pretty pricey. So were Pirelli. Each of the Bridgestones I got were under $130, that was about my limit for tires.