Rebuild

Hi all ive owned this Z750 e1 for 20+ years and only recently got back to working on it , a few months back I got it to run , but since then haven't had much time unfortunately,  I  was stripping back the wiring to fit a different headlight speedo indicators etc and had everything working! But since then ive somehow lost the plot and cannot figure out were this black wire from the right hand side control goes to , looking at the manual could it be part of the start switch? If so I cannot see a similar black on the loom? 
aAlso the clutch engament swith wire thacime from the clutch lever 2x black wires cannot see were these go .
And another thing I  recently found was the rear wheel was incorrect,  a 16"" instead of a 18"" apart from speed what do you think would bd the advantages/ disadvantages of  26/18 "" wheels. 
Thanks for any help and thanks for a great group. 
Phil

The black from the right switch goes to one of the blacks on the clutch switch, the other black from the clutch switch goes into the loom to the starter solenoid

You indicate you have a manual, it should have a wiring diagram in it, but if not here are 2 one for the EU and one for the US.

Hi thanks for this yes I've got both the clymer and the haynes,  both are in black and white and its hard to trace the wires , the colour will make it alot easier, thanks both for your help, I'll get  back to it next week, once these work shifts are over and will try again.
 

If you want a Kawasaki manual there is one for the E and H models located in the filebase section on this site. It is pretty easy to use but here is a direct link to it. Keep in mind one needs to be logged on to the site to have access to it.
kzrider.com/filebase-alias?view=download...vice-manual&catid=17

I hope you meant to type 18\16 rather than 28\16! Kawasaki used 16 rear and 19 front rims on the LTD, Spectre and I think CSR to give those models a cruiser look. If you like that look, use them. If you prefer the sportier look, use an 18 rear wheel. Keep in mind that you want to stick close to stock overall diameter of the tires. Messing with different diameters can change the steering geometry and maybe in a way you don't like.. Raising the rear of the bike can quicken the steering a bit. Raising the rear and lowering the front can lead to twitchy handling. Too much in that direction can introduce a tank slapped and much sadness, not to mention brown underwear.

Thanks for the reply,  I really didn't think about the difference in geometry,  good point ,  l just thought about different speed,  luckily I  have a good 18"" wheel I think I'll stick with the 18""  stock ,is the Ltd a different frame then ? 
thanks again 
Phil

the Ltd frame is different. different steering head geometry and doesn't have the extra frame tab-ing and brackets for a tail cover. maybe etc. it does have some similarities.

manual. there's a factory service manual pdf available. should be linked here in the filebase. or try the 750Turbo site.  yellowish cover w color wiring diagrams. kz bike night KZ750L3 has color wiring diagrams. but the pdf manual there is black-&-white.