1981 Kawasaki KZ750 Resurrection

[Nessism]

You mean that Supertrapp is for a GPz750?Which year?The 82 or 83 and later?Got me going just thinking about itNot that I could afford it even if you wanted to sell itJust wondering while I'm thinking to ask alloy can or steel?

Not sure on the year. The header is the same for the regular 750 and GPZ, but the muffler and midpipes vary depending on year. The muffler has a steel midpipe and then an alloy can.

[SVSooke]

Sounds like the system I got on the 85 750EF, alloy cans are the bomb

[Nessism]

Decided to put the bike to dead stock before doing anything more. The pipes look good, just as long as you don't get to close and see the rust speckling in the chrome.

Engine is running. I'm embarrassed to admit how much time I wasted fussing with the cam timing before realizing I had the signal generators mixed up. 1-4 was switched with 2-3 and the engine lit off immediately. Have to fix an exhaust leak on the header attachment to the head but the engine sounds good otherwise. I'm not going to mess with the cams/coils any further until the valves need to be adjusted. This engine is shim under bucket so the cams need to come out to adjust the valves. I'll fix the issue properly next time the cams are out.

[Joe H]

Very nice looking! A-1!!

I had an exhaust Jet hoted', really, really tuff stuff, very bullet proof on mine, but costly. They did inside and out in matt black and it looks good after more than 10 yrs.

[Nessism]

Thanks for the kudos Joe!

Got the exhaust leaks sorted out. Love the way the stock exhaust sounds; throaty with a good rumble at low speed, but not overly loud. I'm going to ride the bike around a little bit before pulling the exhaust back off for refinishing.

Next up is working out mounts for the horn and the lower oil cooler mounts. And speaking of the oil cooler, the oil capacity is listed as the same for both the Gpz750 (with cooler) and the KZ750 without. Not sure what's up with that. After running the bike the oil level drops a lot. I added some extra oil but after waiting for an extended period of time the oil cooler drained and the oil is at the top of the sight glass now. Think I'll just leave it there. My oil pressure light isn't going off so gotta look at that too. Based on the oil level dropping as it does it's clear the oil pump is doing it's thing. Might throw a gauge on there to check just for kicks. At any rate, getting close....

[rustybronco]

At any rate, getting close....

And eagerly waiting for the finished product.

[Nessism]

And eagerly waiting for the finished product.

Thanks Dale!

Fixed the oil pressure light. Forgot to hook up the wire to the sensor.

Gotta vacuum sync the carbs and throw the tank on, then double check all the various critical fasteners. Should be able to test ride this weekend.

[Nessism]

Checked the charging system voltage and found out it's not (charging that is). Using a SH775 so figured it's the stator, which looks quite good and shows 70+ VAC. Installed another (used) stator and same thing. This one shows 75 volts AC. Tried the old shunting R/R and same thing. Getting my ass kicked here.

Thinking about installing the SH775 on my 1000S to confirm it's okay. I had it on there before and it worked but just want to confirm before ordering a new stator.

EDIT: bad stator (two of them). Ordered a Rick's

[Nessism]

Following up just a little on the above charging system post...

Had two different stators that put out good no-load AC voltage (70+), but neither seems able to generate enough power to properly charge the battery. Best voltage I saw is 13.5 volts. Checked leg to leg resistance on one of the stators and it shows .8 ohms, with .7-.4 being the spec. Not sure my volt meter is capable or reading down to this level of accuracy though. I tried three different R/R during this frustrating troubleshooting exercise so pretty certain the stator is at fault. Just goes to show that even if the AC voltage looks good, this does not mean you have a good stator.

[Gorminrider]

...I would put a household light bulb on the legs and see for myself if power is being produced. it's pretty hopeless checking resistances on these except a straightforward grounding.
...I guess I might isolate the charge system to just charge the battery while running the bike from a discharging car battery...something like that may indicate where it's going on for sure.

Or even...13.5v with the headlight on high beam wouldn't bother me too much..one of my homewound stators seems very happy at max 13.8 and maybe these are the same.

[Nessism]

...I would put a household light bulb on the legs and see for myself if power is being produced. it's pretty hopeless checking resistances on these except a straightforward grounding.
...I guess I might isolate the charge system to just charge the battery while running the bike from a discharging car battery...something like that may indicate where it's going on for sure.

Or even...13.5v with the headlight on high beam wouldn't bother me too much..one of my homewound stators seems very happy at max 13.8 and maybe these are the same.

Well, I have a known good R/R (a Compufire as well as a SH775, both that have been tested on another bike), I made a very short and direct harness so I know that's not the problem, and yet the max voltage I'm getting is 13.5V. It's gotta be the stator. Measuring the stator resistance shows about .7-.8 ohms. I wouldn't scrap a stator based on this test but it does show something is marginal. Choices are get a new stator (I placed an order), or live with the low charging voltage. I do most of my riding these days around town where the rpm's are fairly low, so didn't want to ride around with the charging voltage just barely able to keep up.

[salty_monk]

I have a spare stator (for a GS1000) & a known good Mosfet RR if you need to borrow...

[SVSooke]

As far as I know 13.5 will charge a battery just fine.My 85 750 does just fine with numbers like that.

[Gorminrider]

... 13.5 is definitely "charging" but admittedly it is not charging to a good battery's maximum charge rate...that is, when you start your bike (say it's slow to start and the battery is half-discharged...) regulation at 14.2v means more current is flowing "in/through" the battery and charging it "quicker".. than 13.5v is.
A 10 or 15 amp output should easily do this on a motorcycle battery.

yes,in the end, slower charge or not, a "resting" battery (not being charged) that displays 12.58v or so IS charged fully. It just takes longer. No doubt there'll be difference of opinion on this but put it this way-practically speaking you shouldn't have to futz with it in "normal riding".
I think the stator output should easily charge the battery from a half-dead condition in about a half hour or so give or take some tapering off. And
so I certainly see your point, nessism. The 13.5 indicates a less than optimum output. If you paid for it, it should do it. I can only winge and suggest that the battery of the subject bike might also be swapped.. ignore if I missed that.
especially when the R/R works on another bike and gives the "proper 14+volts,
especially, ( per your special harness) when the motorcycle battery is not doing any "work" (at the starter motor or accessories like heated handgrips or xtra running lights) while being charged, it should certainly have a charge current and voltage that requires regulation.

and if it can't make even a regulated float charge of 14+ vdc, That is very odd. Even if your stator tested "open" @ 50VAC - 60 VAC it should that.

[Nessism]

Slammed in the new stator and now charging at 14.5 volts. Very happy. Just goes to show that no load AC voltage is not a proper indicator of stator health. The new stator has .7 ohm resistance between legs, the marginal stators had .8 ohm. A seemingly minor difference.

Cleaned up all the wiring including adding redundant R/R ground and power out wiring. Kawasaki runs the power out straight to the battery with no fuse in between. Jim (Posplayr) would have a heart attack. I'm just going with it for now...