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I hate carburators!
- Fugitive
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1979 KZ1000ST
4 into 1 exhaust, Kerker style but no emblem.
Individual pod air filters.
Valves clearances set. New spark plugs. Good compression.
Stock carbs, not sure what exactly they are but they do have an acc pump. Thoroughly cleaned and kits installed.
110 mains
15 pilot jets
Needle valve c-clip set on second to bottom, idle too rich even with set air mixture screws all the way in, but otherwise runs ok.
Moved c-clip to center position. Idles great with mixture screws about 3/4 turn out but coming off idle (like rolling out of a corner) leans out until into the throttle about 3000 rpm.
Went to 120 pilot jets to attempt to clean up the low range but now too rich at idle, even with mixture screws all the way in.
Not sure what to do next? Move c=clip on needles up one more?
Any advise will be appreciated. Thanks in advance.
Fugitive.
'79 KZ1000ST
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- Nebr_Rex
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2002 ZRX1200R
81 GPz1100
79 KZ1000st daily ride
79 KZ1000mk2 prodject
78 KZ650sr
78 KZ650b
81 KZ750e
80 KZ750ltd
77 KZ400/440 cafe project
76 KZ400/440 Fuel Injected
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- arai59
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- Fugitive
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'79 KZ1000ST
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- MFolks
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You might be a candidate for the "Wired George" ignition coil relay modification. www.wgcarbs.com is his website. He lists parts and how to wire the older Kawasaki's. The mod improves the primary side voltage to the coils producing a hot,fat, spark for improved combustion efficiencies.
To check the coils for low voltage, remove the tank, and with the ignition turned on check the input voltages at the coils. If it's less than battery voltage you have a voltage drop robbing the coils of full output and weak spark.
One guy here did the modification and had to crank down the idle 500 rpm's due to the bike running like new.
1982 GPZ1100 B2
General Dynamics/Convair 1983-1993
GLCM BGM-109 Tomahawk, AGM-129A Advanced Cruise Missile (ACM)
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- bountyhunter
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Any advise will be appreciated. Thanks in advance.
Get a stock airbox, it might save you a lot of misery.
120 would be a main jet. Increasing the main jets can't possibly fix a low range problem. They work most at 3/4 - full throttle at RPM range from about 1/2 (redline) up to redline. If it pulls strong in that range, the mains are correct.Went to 120 pilot jets (?) to attempt to clean up the low range but now too rich at idle, even with mixture screws all the way in.
Pilot jet size, needle position, and even fuel level in bowls influence the low range running and throttle response. The diameter and taper on the needles is designed for the flow set by the stock headers and airbox. Change that and the taper doesn't match. usually you can jet in headers, pod filters are known for being difficult to get to match the needles.
1979 KZ-750 Twin
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- Patton
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- KZr Legend
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...1979 KZ1000ST
4 into 1 exhaust, Kerker style but no emblem.
Individual pod air filters.
Valves clearances set. New spark plugs. Good compression.
Stock carbs, not sure what exactly they are but they do have an acc pump. Thoroughly cleaned and kits installed.
110 mains
15 pilot jets
Needle valve c-clip set on second to bottom, idle too rich even with set air mixture screws all the way in, but otherwise runs ok.
Moved c-clip to center position. Idles great with mixture screws about 3/4 turn out but coming off idle (like rolling out of a corner) leans out until into the throttle about 3000 rpm.
Went to 120 pilot jets to attempt to clean up the low range but now too rich at idle, even with mixture screws all the way in.
Not sure what to do next? Move c=clip on needles up one more?
Any advise will be appreciated....
Good advice from MFolks and bountyhunter.
FSM for 1979 KZ1000-A3/D2 shows Mik VM28SS, side located pilot air screw (1.25 +/-.25 turns out from lightly seated), 105R main jet, 15 pilot jet, 5SCN15-3 jet needle (middle clip), O-1 needle jet, service fuel level 4mm +/- 1mm (from edge of carb body to fuel level).
1979 KZ1000ST might possibly be different.
Reported history includes compression okay, but nothing about spark quality, ignition timing, advancer function, fuel level, whether pod air filters are clean and allowing adequate air supply, or choke plungers properly closing and sealing.
Side located pilot air screw governs amount of air allowed into pilot circuit. Turns in for richer, out for leaner. All the way in allows zero air for max richness. Only 3/4 out is still too rich. Pilot air passage may require further cleaning.
Clip position or main jet size has negligible effect on pilot circuit.
Good Luck!
1973 Z1
KZ900 LTD
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- Nebr_Rex
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2002 ZRX1200R
81 GPz1100
79 KZ1000st daily ride
79 KZ1000mk2 prodject
78 KZ650sr
78 KZ650b
81 KZ750e
80 KZ750ltd
77 KZ400/440 cafe project
76 KZ400/440 Fuel Injected
www.dotheton.com/forum/index.php?topic=39120.0
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- otakar
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Otto
Otto
74 Z1-A stock
76 KZ-900 Totaly stock vice MAC pipe
77 KZ-1000A stock
78 Z1-R 100%MINT 500 original Mi.
78 Z1-R Yoshi 1103 kit stage 1 cams Yoshi pipe. Etc
79 KZ-1300 (1400)
80 KZ-1300
81 Scratch built GPz1150R
82 KZ1000
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- Old Man Rock
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now too rich at idle, even with mixture screws all the way in.
Patton hit it on the nose on this one.... Of course it's going to be rich.....
We all hate carbies but that's mostly because we don't understand them... Thus we must LEARN them....
Colortune is in order here..... :laugh:
OMR
1976 KZ900-A4
MTC 1075cc.
Camshafts: Kawi GPZ-1100 .375 lift
Head: P&P via Larry Cavanaugh
ZX636 suspension
MIKUNI, RS-34'S...
Kerker 4-1, 1.5" comp baffle.
Dyna-S E.I.
Earls 10 row Oil Cooler
Acewell 2802 Series Speedo/Tach
Innovate LC1 Wideband 02 AFR meter
Phoenix, Az
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- Fugitive
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Fugitive.
'79 KZ1000ST
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- wiredgeorge
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Mik VM28SS ID 1098
Service Fuel Level 4mm
Main jet #102.5
Jet needle 5CN17-3
Needle jet 258 O-4
Slide Cutaway 2.0
Pilot jet #15
Air Screw 1 1/4 turns out from lightly seated
First thing, check coil voltages, Next, turn air screws out to 1 1/4 turns out from seated and third (!!!!!) never oil paper element air filters (like yours).
Remove #4 pod air filter and twist throttle while the bike is parked on center stand and not running. Do you see gas squirt out of the accelerator pump squirter into the venturi? If not, clean the accelerator pump circuit because jetting will change if the thing isn't working.
If the pump IS working, go with #115 main jets, #20 pilot jets (IF YOU HAVE REAL GOOD SPARK - SEE COIL REPOWERING TIP) and reclip the jet needles to 4th slot. Slots are numbered 1 - 5 from top to bottom. You will need to resync carbs AFTER pulling out the slides as the M5 bolts holding the slide actuators to the slide rod change tension when you retighten them and sync will be out of whack.
Once you get the bike idling, turn air screws in/out about 1/2 turn to try and achieve max idle. Keep an ear open to idle change as the tach isn't very accurate at lower rpm. If no idle change occurs, don't be concerned as the air screws don't effect the air/fuel mixture a ton and just leave the screw at 1 1/4 turns out. Turn screws in and you richen and out and you lean as more air is allowed into the pilot passageway.
Oh yeah, nice bike... here is my 79:
wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
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