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Plug wires and coils
- muddytailgate
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While fighting with my '78 kz650 over an apparent timing issue, I noticed a waxy material under one of the coils (1-4). It looks like there is a small crack underneath.
I also noticed that the plug wires do not seem to be removable from the coil side. I guess my first question is... are these wires part of the coil and not removable? Followed by...could these be the original wires?
Thank you.
1976 KZ 750b
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- bountyhunter
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Z1 Enterprises sells a $36 OEM type coil for Kawis that will work in your bike but it is a four Ohm coil and yours may be a little lower impedance. You might get slightly less spark energy using a four Ohm coil but I doubt you would be able to tell the difference.
1979 KZ-750 Twin
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- muddytailgate
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After frustration though, I was adjusting timing and dwell all over the place in attempt to get SOME result even if it was a bad-but-different result. Not matter what though, it just runs very lazy. Since I have owned it, I have put 1200 miles on it but I think previously she spent most of her life outside and un-ridden. She is rusty with only 10,000 miles.
Do you know how these bikes behave with faulty wires and/ or coils?
1976 KZ 750b
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- MFolks
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For higher spark energy, get some non resistive sparkplug wires and eliminate the resistive sparkplug caps.I'd check the input voltage to the coils to see if a corrosion problem in the connectors is giving you problems.
Remove the tank,turn on the ignition, run/stop switch to run, and put the RED probe of a multimeter where the RED wire goes. Set the multimeter to VDC(Volts D.C.) range of 20, with the BLACK probe either on a good frame ground or the Negative battery terminal.
You should have battery voltage or very close, if it's down around 8-10 volts, you have a corrosion problem causing weak spark.The right handle bar switch pod has the run/stop switch along with the start switch.
The headlight housing has a majority of the electrical connectors, any which can cause weak votages for the bike's systems.These need to be cleaned. Also the fuse clips can be a major problem due to corrosion/overheated wires.
www.z1enterprises.com sells a non resistive(copper wires)Dyna sparkplug wires with non resistive caps, just cut to length,install on the coils, and you're ready to go.
1982 GPZ1100 B2
General Dynamics/Convair 1983-1993
GLCM BGM-109 Tomahawk, AGM-129A Advanced Cruise Missile (ACM)
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- Patton
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...runs very lazy...spent most of her life....
Would assure advancer is functioning correctly. May need lube, or maybe both clean and lube.
Good Fortune!
1973 Z1
KZ900 LTD
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- Patton
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1973 Z1
KZ900 LTD
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- muddytailgate
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A little more background on the bike. Up until last week this thing was running pretty good. When I bought it I put new points and condensers. Like I said before, I put 1200 miles on it and it went down the road pretty good...85 mph at the top of 4th gear. Now it barely makes it down the road. I has always stared easy (even now) but don't even think about going down the road for a while...like 10 minutes.
Advance seems to operate freely.
1976 KZ 750b
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- ace
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- 78kz1000
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78kz1000
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- bountyhunter
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The dyna coils are typically lower impedance and draw more current. I don't know what coil impedance yours came stock with. You can normally go with a coil which has a slightly higher impedance than stock no problem but going lower impedance can cause overheating, excess current, and coil failure. I think if your kaw has the electronic ignition, the stock coil is about 3.3 Ohms. If you have points, it takes a four Ohm coil like the $36 one at Z1.im looking at new coils also and wires andcaps.... whats the diff between dyna coils and the 36 dollar ones from z1? besides the price??? i currently have all original 1978 setup.
1979 KZ-750 Twin
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- Becker
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- The Doctor Will Rise Again
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78 KZ750B3
79 KZ400 LTD
78 KZ650C2
79 KZ650C3
78 KZ650B2A
80 KZ650F1
80 KZ650E1
81 CB750K Super Sport
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- Patton
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... barely makes it down the road....
Perhaps combusting on just two cylinders.
Would spray water mist onto exhaust header pipes with engine running to determine which cylinders are combusting.
Good Fortune!
1973 Z1
KZ900 LTD
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- muddytailgate
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I have not cleaned carbs although I am sure they need it. I am planning a complete teardown this winter but didn't to open that worm can during riding season. Already have an Aermacchi rebuild going. I bought this as a el-cheapo-2up-backroad-rider to get my wife into riding with me. I have created a monster..."is it fixed yet, is it fixed yet"...
1976 KZ 750b
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