1981 KZ750 LTD four questions

Cool thank you! Out of curiousity how did you come up with the add 3T to stock though?
And you said 16T for the front sprocket but then listed a 15T in the second part of your reply. I thought I saw a 39T rear but I may not be looking at the right thing. I'd just call Z1E but their phone number doesn't seem to be listed anymore - sent and email but that may take a while to get back... 

wrote:

Cool thank you! Out of curiousity how did you come up with the add 3T to stock though?
And you said 16T for the front sprocket but then listed a 15T in the second part of your reply. I thought I saw a 39T rear but I may not be looking at the right thing. I'd just call Z1E but their phone number doesn't seem to be listed anymore - sent and email but that may take a while to get back... 

My bad on the 15 vs. 16. 16T is correct.  You can check yourself using one of the many sprocket calculators around on the internet.  Compare the "pitch diameter" of a 13T 630 sprocket to a 16T 530 sprocket.  They will be very close in size.

Alright crew here's another one - did an oil change on this bike and put in 3qt of 10w40 full synthetic as a starting point so we'd be nice and happy between the low and high fill marks. I've ridden the bike about 40 miles since and the other day went to hop on but checked the oil before taking off the center stand. We were at the bottom of the eyeglass....I'm stumped. Not leaking anywhere under the bike, plugs aren't fouled, although there is a decent amount of carbon on the piston heads (24.8k miles on the clock). I'm wondering if it's valve seals? When I had plugs out I hand spun the engine and there was definitely oil on the seat of the valves that I could see. Thoughts? 
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Also because it isn't in the manual the I found, and a few people seem to have the same question here is the loading info for the 1981 KZ750 H2 LTD straight off the stem:
GVWR 860 LBS
GAWR FRONT 375 LBS with stock wheel/tire at 25psi
GAWR Rear 562 LBS with stock wheel/tire at 25psi

hope someone else finds this useful! Thanks! 

Only 3 quarts?  No wonder it is low on oil.  Why didn't you put in the correct amount of oil to start with?    Ed

Because I'm a cheap bastard and rather than put in 3.5 I put in 3, since that brought it to about the middle of the sight glass, and there's a small chance it's going to all get drained again soon anyways. 

When changing the oil it is not unusual for the oil in the site glass to be a bit high until the bike's engine has run and been allowed to cool down.  I suggest you put in the correct amount of the correct type oil and then see if the oil level goes down after a ride.  Be sure the oil is JASO-MA compliant.  That should be shown on the oil container's label.  Using the wrong oil can ruin the clutch.  Ed

Went to change the fork oil and seals because who knows when it was done last... Photos of the old seals and retainers attached. Yikes. 

In my disassembly, there was a part that seemed to be missing but the parts diagram is somewhat unclear. In the service manual it is called the piston ring, and resembles a washer, but in the OEM parts diagram it is part of the piston/cylinder unit. Neither fork had such a ring but each did in fact have a small black ring that fit into the groove at the top of the piston/cylinder.... Are they the same thing? 

Almost ten years later, and this thing is still kicking. Two weeks ago, I had my first crash and I was fortunate enough to miss all the boulders on the side of the road and more or less walked away with a lot of severe bruising. The bike definitely took the brunt of it, but all things considered we're looking at mostly cosmetic damage to the bike, but of course it's all the expensive bits like the exhaust, tank, and instrument housings. That being said, I've managed to find another, this time a 1980 KZ750 that's been sitting outside for who knows how long and while some things are roached (seat, tank, mirrors) the bike is in surprisingly overall good condition and with only 7k on the clock and oil in the engine still, it turns freely! 

So I'm at an impasse - I can use it as intended as a parts bike to fix "my" bike with 26k on it that I love dearly, or I can swap good parts from my bike to this new project. But that's for mulling over some more later perhaps with a few fingers of bourbon and a campfire. For now, I just want to get back on the road. 

That said, looking at part numbers and diagrams most everything should swap fine, but I noticed the gauges on the parts bike are slightly different in terms of what indicator lights are on which pod, as well as the addition of a voltage meter on the tach side of the 1980 not present on my 1981. I know the mechanical tach and speedo will be fine, but am I correct in guessing getting the electronics to work will just be a matter of matching the correct wires to the correct pod? What about that voltage meter? 

The other curiosity was the swingarm on my 1981 has no grease fitting which I always thought was odd - the swingarm on the 1980 DOES have one and I was considering swapping them. Is there a reason it was deleted on the 1981 that anyone knows of?

Glad to have found this community and be a part of it.

The other curiosity was the swingarm on my 1981 has no grease fitting which I always thought was odd - the swingarm on the 1980 DOES have one and I was considering swapping them. Is there a reason it was deleted on the 1981 that anyone knows of?

Probably cost. 1 less part. 1 less step in the mfg process drilling/tapping the hole. 1 less step in the labor process.
possibly because most riders who have it ignore the thing. ha ha.
 

As mentioned, they probably deleted it for cost savings. My 81 1000 LTD didn't come with one either. When I did a frame up resto on it several years ago I saw how bad the swingarm was and installed a zerk fitting in it myself.

Update - bike is 95% back together after frankensteining a couple of turn signals together from crashed parts and parts off the parts 440. Different internals on them much to my chagrin. Did bearings front and rear last weekend, new tires, lubed everything, chain aligned and slacked, new gear ordered... went for a very quick half mile ride for a preliminary shakedown aaaaaand Carb issues. Starts great, runs at idle with half to full choke and once it starts to warm and I start to let the choke off, surges to 4-5k until I touch the throttle (dies) or choke it back up (returns to normal idle). Pulled the carbs and went through them again, crap in the bowls and all around the bowl gaskets. Replaced all four float needles, gaskets and main jets because I had them all on hand, pulled the slides while I was at it and discovered 3 pinholes in #1... pulled a donor from the parts 750 I picked up to fix this after the crash and cleaned it up. Cleaned everything up real nice and blew dry with the compressor (slides and floats out, per FSM)  Got everything back together, just waiting on some clear fuel line and a filter, because I've learned and said it enough times "Next time, I'm putting a filter in line!" 

Hopefully that's all for the summer other than an oil change and regular maintenance items! Bike at least went down the road in a straight line on the half mile shakedown! Can't wait to get back out but definitely not rushing anything. Want it all to be 100%

Another weekend in the garage... fuel filter(s) came in, one is HUGE and the other is the classic conical bronze one you see everywhere. Didn't realize the barbs on that one are 1/4" instead of the 5/16 fuel line I got... enter pocket torch and straight pick to carefully open it up a bit. Success and no leaks, correct filter will be ordered. Float levels set by clear tube method although I had some issues with the bubbles sticking in the tubes, not wanting to allow the fuel out the drain tap on the bottom of the bowl. No idea why - any thoughts? Levels were all close but a couple were low (lean). Really wished that float levels were reliable because what a PITA taking everything apart and back together and apart... would be easier if I had an auxiliary tank and a jig for the carb body... maybe another day. 

Levels set to 4mm +/- 1mm from bottom of carb body with carbs level. Filter installed. Bike starts idles well. No surging. Went for a 15 mile ride and the first time I had to slow down... bikes hanging at 4-5k rpm. Booooo. Made it home fine, tore the carbs all the way down again. Tiny bit of junk in the bowls made me realized I had forgotten to flush the fuel tube that connects the 4 carbs... some junk came out of there as well. Was reading another post on the pilot air screw which I've not touched before on this bike. Put on my brave pants and opened them up and they were in fact, filthy. Screws looked fine after cleaning, replaced o rings, gave the passages a good cleaning with carb cleaner and a tiny soft bottle brush. Cleared out the tiny air passage above the screws as well - they were clogged and one was actually partially blocked - looks like something dinged the aluminum up there somehow just enough to fold it over that orifice. Still going to run the Pilot System Cleaning diagram I've seen floating around here before reinstallation, and maybe check fuel levels again one more time for good measure. 

Beyond that I want to check valves (27k on the bike, no idea when they were last done) and vacuum sync the carbs. Should one or the other of those be done first? Thanks all!