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Done Everything, Still Has Hanging Idle
- redwood
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- 81 650 CSR
Rev the engine, every now and then it hangs up around 4k or so, doesn't happen every time.
-No air leaks, guaranteed.
-Carbs have been cleaned semi-professionally (friend runs motorcycle restoration business, took them apart, cleaned ultrasonically).
-Advancer does not stick.
-No cables binding, brand new cables.
-Idle set properly.
-Adjusted the valves a few days ago.
Could the carbs be at fault? Leaking gas into venturi from somewhere?
Could the air injection system be doing something detrimental? I guess I could try blocking the valve cover ports and see if that fixes it.
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- MFolks
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Tried the trick of spraying carb cleaner on the hoses/lines while the engie is running? If the rpm goes up, you've found your leak.
1982 GPZ1100 B2
General Dynamics/Convair 1983-1993
GLCM BGM-109 Tomahawk, AGM-129A Advanced Cruise Missile (ACM)
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- anarki650
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09 Kawasaki ER6n
77 kz650b1 cafe rebirth project
"Being shot out of a cannon will always be better than being squeezed out of a tube, that's why God made fast motorcycles..."
Dr. Hunter S. Thompson
Omaha NE
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- redwood
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I'd like to say the carbs are completely clean, but maybe something didn't cleaned up properly? What could it be?
I've sprayed all up and down this thing, no leaks. The only place it could be leaking is where the vacuum line meets the carbs on that brass plug. But it should have been reseated properly after the cleaning.
Would incorrect float levels cause this? How can it if the slides close after blipping throttle?
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- otakar
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In my experience hanging idle usually means lean.
+1 but it would help if we knew what type of carbs we are talking about. That way we can narrow it down to, Mechanical, Vacuum, Fuel delivery, Fuel supply. Also we need to know if you are using a stock air filter, or if you changed into pods. Pods will change the entire dinamics of carbs especially CV carbs. Some CVs must be quite a bit modified to work with pods at all.
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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- redwood
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- Bluemeanie
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1980 KZ650F1, Bought new out the door for $2,162.98!
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- redwood
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- Old Man Rock
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Maybe I missed it but when it hangs on high idle, whats the position of the carb return spring mechanics?
Meaning, is it still above the stopper bolt...
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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- otakar
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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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- anarki650
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What do the plugs look like? A lean cylinder would give you a white(ish) plug, would possibly help narrow the search to know that info. If all plugs are reading correctly I'd be inclined to agree that a throttle cable might be binding up.
09 Kawasaki ER6n
77 kz650b1 cafe rebirth project
"Being shot out of a cannon will always be better than being squeezed out of a tube, that's why God made fast motorcycles..."
Dr. Hunter S. Thompson
Omaha NE
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- hardr0ck68
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- Who put the what in the where?
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My quick fix was a zip tie to lock the bracket in place; next time I pull the carbs for a jet change (spring) I will drill out the rivets and put a couple nut/bolts there to lock it down tightly again.
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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