1982 GPz-750 (KZ750R1)

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SonicVenum
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Re: 1982 GPz-750 (KZ750R1)

Post by SonicVenum » Tue Nov 04, 2014 4:26 pm

I have a brand-spanking new battery, and the starter has been rebuilt. Some of the parts were worn enough that is was causing a short when I tried to start it. The it took some minor fiddling, but I got the inexpensive kit to work. While I had the sprocket cover off, I thoroughly cleaned the chain, and lubed it. I also cleaned up all the gunk from the area, reconnected the neutral switch (which was disconnected for some reason), and adjusted the clutch. Unfortunately, all my efforts have still not ended with a running bike, though I'm getting close. It'll turn over just fine, but it won't turn on. I turned on very briefly on two occasions, but I couldn't not get it to stay on for more than a couple seconds. I'm going to check that all four plugs are getting spark because one or both coils are known to go bad. Air/Fuel/Spark. Air shouldn't be an issue with freshly cleaned and oil pod air filters. Fuel shouldn't be a problem with new fuel line, disassembled/inspected/cleaned fuel petcock, freshly cleaned carbs (along with setting the float height), and a brand new fuel filter. So, my first guess is spark or some other electrical issue. Let the diagnostics begin. :dance:

jhwalker
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Re: 1982 GPz-750 (KZ750R1)

Post by jhwalker » Tue Nov 04, 2014 7:11 pm

:clap: Keep digging.

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Brakelate
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Re: 1982 GPz-750 (KZ750R1)

Post by Brakelate » Thu Nov 06, 2014 5:14 am

Go back and re-visit that disconnected side stand safety switch. Sometimes, especially down there, subjected to many miles and years of road grime, chain lube, etc they stick up. Perhaps that is why it was disabled in the first place. Few disconnect that as a matter of preference. Some disconnect the clutch-in or neutral safety switches so they can turn the bike over in gear or without having to pull in the clutch, but the side stand switch is usually a transparent safety feature. So it may be faulty or intermittently crapping out, causing it to cut ignition at random times. Simple test. At least eliminate it from the list of suspects. It's a quick test.

SonicVenum
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Re: 1982 GPz-750 (KZ750R1)

Post by SonicVenum » Thu Nov 06, 2014 7:56 am

The neutral switch is the one that was disconnected, but I think it's just because the connector was a little loose, and it slipped off. I tightened it up a bit, and cleaned up the area, before reconnecting it. From looking at the wiring diagram, the neutral switch is only connected to the Neutral indicator light on the instrument panel, so it shouldn't affect start up. The side stand switch is wired into the starter circuit, but I didn't mess with that at all. I tried starting it with the stand in both positions, and the only difference was that the stand warning light flashes when it's down.

I just got an in-line spark tester, and a new multi-meter, so hopefully those will help narrow it down. Something else I noticed, which may be indicative of a problem is that the battery warning light flashes when I turn the key to "ON". That's weird because the battery is new, and I have it on a battery tender, so it should be at full charge. Getting this thing on the road will be satisfying once it finally happens. What started as, "one of the carbs is clogged," has turned into quite a bit more. Good thing I got it for an unbeatable price. :-D

SonicVenum
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Re: 1982 GPz-750 (KZ750R1)

Post by SonicVenum » Thu Nov 06, 2014 4:04 pm

It's running! :mrgreen: Turns out I'm a goofball, which you all already knew. When I bench-synced the carbs, I left the idle screw too far in, so I had to back it out quite a bit to get the thing started. I let it warm up for a bit with two fans on it, so it wouldn't get too hot. Once warm, I did a vacuum-sync on the carbs (#4 to #3, #1 to #2, then #2 to #3). It's idling nicely, and the V&H 4-into-1 sounds wicked. I'm pleased. Now I have to mess with the clutch cable because after I warmed up the bike, when I squeezed the clutch cable to re-start it, it kinda just crunched, and won't return like normal. The cable sleeve seems to have come loose from the lever adjuster, and adjuster in the middle of the cable. Either way, that shouldn't be too bad to take care of. The important thing is... she's ALLIIIIIVE! :auto-biker:

jhwalker
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Re: 1982 GPz-750 (KZ750R1)

Post by jhwalker » Thu Nov 06, 2014 4:15 pm

SonicVenum wrote:It's running! :mrgreen: Turns out I'm a goofball, which you all already knew. When I bench-synced the carbs, I left the idle screw too far in, so I had to back it out quite a bit to get the thing started. I let it warm up for a bit with two fans on it, so it wouldn't get too hot. Once warm, I did a vacuum-sync on the carbs (#4 to #3, #1 to #2, then #2 to #3). It's idling nicely, and the V&H 4-into-1 sounds wicked. I'm pleased. Now I have to mess with the clutch cable because after I warmed up the bike, when I squeezed the clutch cable to re-start it, it kinda just crunched, and won't return like normal. The cable sleeve seems to have come loose from the lever adjuster, and adjuster in the middle of the cable. Either way, that shouldn't be too bad to take care of. The important thing is... she's ALLIIIIIVE! :auto-biker:
:clap: You have inspired me to work on my bikes this weekend... :whistle:

SonicVenum
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Re: 1982 GPz-750 (KZ750R1)

Post by SonicVenum » Thu Nov 06, 2014 4:48 pm

We all need inspiration. Haha. I became inspired by watching many episodes of Wheeler Dealers after a long time not watching it. Watching good ol' Edd China toil away at restoring modern "classics" gave me a bug that wouldn't let up until I got back to working on the bike. It started with the car first. I did a few things on that, but I felt bad for having the bike just sitting there under a moving blanket. Once I started tearing into the bike, I was motivated to get the thing going. I think it might be running a bit rich, but I have to get it out on the road, and open it up before I'm sure of it. I have to get my license plate mounted, and get the bike registered before I can really get it out on the road. Luckily, the neighborhood near our house has no outlets to the main street, so I can ride around up there to sort things out.

jhwalker
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Re: 1982 GPz-750 (KZ750R1)

Post by jhwalker » Thu Nov 06, 2014 6:21 pm

SonicVenum wrote:We all need inspiration. Haha. I became inspired by watching many episodes of Wheeler Dealers after a long time not watching it. Watching good ol' Edd China toil away at restoring modern "classics" gave me a bug that wouldn't let up until I got back to working on the bike. It started with the car first. I did a few things on that, but I felt bad for having the bike just sitting there under a moving blanket. Once I started tearing into the bike, I was motivated to get the thing going. I think it might be running a bit rich, but I have to get it out on the road, and open it up before I'm sure of it. I have to get my license plate mounted, and get the bike registered before I can really get it out on the road. Luckily, the neighborhood near our house has no outlets to the main street, so I can ride around up there to sort things out.
All good stuff. One of the problems I have is that here I can have a talented guy work on the bike for 8 hours for $15 -- and if I am doing "my stuff" -- the things that I am pretty good at -- I can make many multiples of that without the back pain blah blah. I have that motorcycle lift coming in which may make the working a lot easier. I admire that you have stayed on this project...

SonicVenum
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Re: 1982 GPz-750 (KZ750R1)

Post by SonicVenum » Thu Nov 06, 2014 9:17 pm

If I had access to labor that cheap, I'd be very tempted to use it, rather than get greasy myself. Although, there's a certain level of satisfaction that comes from getting something working with your own two hands. I'll admit that tearing into the carbs, which I had never done before, was a little scary at first. But, hearing the throaty growl of my little 750cc machine breathing through that aftermarket exhaust made all the blood, sweat, and tears worth it.

jhwalker
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Re: 1982 GPz-750 (KZ750R1)

Post by jhwalker » Fri Nov 07, 2014 8:12 am

I'd rather do it the way you are doing it, which is why I ordered the lift. I went back and looked at the original pictures. Are you doing all mechanical before taking on the looks? (You probably answered this but I was too lazy to review the longish thread).

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