Question about 1992 Honda CB 750 Nighthawk

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1992 cb750, I have a dead spot coming off idle then at about 2500rpm it wants to pull the handlebar out of my hands. Seafoam is helping clean it up; Will it clean all the way or will have to remove carbs for cleaning?

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Posted on Jan 02, 2017

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SOURCE: 1995 honda cbr f3 wont start

I would think about investing in a carb re-build kit.

Posted on Dec 22, 2008

  • 3 Answers

SOURCE: very stiff throttle cb750

I had the same problem with my dads old bike that had been sitting for 10 years. What I had to do was take them off and keep wiggling them back and forth while adding copious amounts of liquid wrench. It took several sessions but the throttle snaps open and shut the way it should.

Posted on Mar 28, 2009

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SOURCE: J.D snowmobile 340 73 carb wont idle appears internally clean.

my guess is that its not the carb at all but it might be the gas line in side the tank is cloged to the point whare you need to have it on choke in order to pull enough gas to the carb which would be the reason for it not wanting to come back down to idle quickly or it could be the fuel pump is cloged and if you tried that already than the fuel adjustment is way off and will need to be adjusted while a friend or family is keepin it running

and if that is not the problem than email me.
good luck:)

Posted on Jun 02, 2009

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SOURCE: starts and stays running with choke on. stalls

Pay special attention to the parts in red. DO NOT mix parts from the front carb with parts from the back carb. When removing adjuster screws and jets, count the number of turns to remove them, write it down, and replace with the same number of turns.

Go to the site below where you can see a parts diagram for your specific bike. You will select the actual brand, year, model, etc., once you go to the site. Part numbers and prices are also shown. You can order parts from this site. In the event no price is shown on a particular part, the part is not in stock.

Go to this site and you can download a free PDF service manual. Most all of the manuals are in English but some are not. There is no way to be sure without doing the download. You can always delete it if in a foreign language.

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Posted on Jul 02, 2009

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SOURCE: 1981 gl1100 has 4 keihin carbs bike sat 7 years

648d54b.gifWhen removing the pilot jet screw, count the number of turns to remove. Put the screw back the same number of turns then unscrew 1/4 turn.
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Posted on Jul 02, 2009

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2 Answers

1992 GMC Safari Van 4.3 V-6 Engine. Will not come up to idle and dies with-in 3-5 min.

Sounds like throttle body and/or its components,"IAC motor-IdleAirControl motor, TPS-ThrottlePositionSensor. Throttle body/Carb cleaner and SeaFoam @the brake booster.

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Bike only idles for a few seconds (hot or cold) replaced s/plugs cleaned & sync carbs, slugish till around 2500rpm but no problems after that

Clean them better, or check for off Idle fuel adjustments on them.

Also not that garbage in the tank can be clogging the internal strainer reducing flow.

Happening at only the 2500RPM area I would inspect the secondary / Off Idle Jets just above the throttle plates for clogging............ soak them in cleaning solvent, use a torch tip cleaner, blow them out with air ect.

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I have a 1989 honda shadow 600 i can crank it right up and idles great but as soon as i give it gas it sputters and pops out the front head and if i dont let off it will die run seafoam through it and...

The jets are very small in the carb. Once you put seafoam in it you now have to pull the carb apart and clean it the correct way. The seafoam breaks up all the debris and gunk in the float and completely clogs the jets.

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Will not stayed cranked. changed out old fuel, fuel filter, changed oil.

The Virago's have a tendency to clog up the carb. quickly due to sitting for a short amount of time, say a month or 2. Try and run some SEAFOAM in the carb. Remove the fuel line from the tank and force the seafoam into the carb with a turkey baster. Run the carb.s dry as best you can, force the seafoam into the carb. and let it sit for a day or so.Then try and start the bike off the seafoam, it will run and make a lot of smoke. Then hook the tank back up and see if that did the trick. Sometimes it will sometimes not, you may have to pull the carb.'s and clean them by removing the bowls and soaking them in a pan of the seafoam or something similar.

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turn ignition slot over with screw driver then use flat head screw driver to touch the positive and negative terminals on the solenoid making sure to avoid massive sparks and only touch the plastic handle on the screw driver

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Any vacuum leaks? Timing good? egr and o2 sensors good?

Jul 11, 2010 | 2004 Ford Taurus

1 Answer

Missing on one cylender

an engine needs fuel, air, and spark. it sounds like you have spark covered. try injector cleaner. if one brand doesn't work try another. at different times i've had luck with techron, seafoam, and lucas, which are about as different as they can be. its also possible that the problem is the injector itself or the wiring, but try cleaning it first. If the air filter or throttle body are dirty, which is rather likely on a '91, change the air filter and use use carb cleaner or seafoam. Also clean/change the PCV valve and clean the idle air control valve.

Feb 21, 2009 | 1991 Subaru Legacy

1 Answer

Rev counter

The idle speed controller is having trouble regulating the idle RPM to the speed the computer is asking. Go to the parts store and get some Seafoam (about $8/can). Pop a vacuum line off the intake manifold, while the engine is running, and feel for suction. When you find it (it should be sucking air into the manifold), put a tube into the can of Seafoam, and allow the engine to **** up about half the can. You may need someone in the car to hold the RPM around 2000 (the engine will bog and may want to stall out while it's taking in the Seafoam). When half the can has been pulled in, pull out the tube, wait for the engine to stabilize a bit, and put the vacuum line back on. Let the car idle for about 15 minutes so it can burn away the carbon deposits that the Seafoam is freeing up. Rev it up to about 4000 RPM every 10 seconds or so for a minute, and then periodically while the car is idling. You won't believe the smoke that comes out the back of the car, but that's what is supposed to happen - that's the Seafoam burning away the carbon that has gotten all over the inside of the engine, and is likely clogging up vacuum lines, the idle controller, EGR system, etc. It's great stuff.

Save the other half of the can to treat the car again in a week or so, or dump it into the oil, drive 30 miles, and change the oil and filter (it can break down oil sludge and deposits as well). Don't drive more than 30 or so miles though because the oil will be thined out and too much more mileage than that may compromise the oil's ability to properly lube and protect the engine.

You can get a second can of the Seafoam and pour it directly into the gas tank as well, and it'll de-resin the tank and lines, clean the injectors, and clean out the fuel pressure regulator as well. The stuff is as close to magic as you're gonna get and it works great. I've done about 20 cars with it now, and not one person has called back saying that they're car isn't much more peppy, efficient, and smooth.

Aug 30, 2008 | 2003 Volkswagen Golf

2 Answers

Check engine light comes on and goes off

Try putting somw SEAFOAM into your tank. It either your O2-sensor, or EGR-valve. Alot of the time, SEAFOAM will clean these sensor up????

Jul 25, 2008 | 1992 Buick Regal

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