Turned knob to let more gas and/or air in now it cuts out bad
I was using the knob on the side of the bike to get it to idle at a lower rpm, now it cuts out bad in 1st gear. What do I have to do to fix this, I tried turning the knob the other way but it did not work.
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Re: Turned knob to let more gas and/or air in now it cuts...
Drain the carburetors. There should be a screw on the lower side of each carb float bowl. Remove the screw then replace it after the fuel drains. Remove the water trap bowl at the bottom of the petcock, (gas valve). Is there any water or trash in the bowl? Drain a cup of gas from the tank. Is there any water or trash in the cup? Dump it, clean it and re-mount it, (not all bikes have a water trap bowl). Install a fresh set of stock NGK spark plugs. Turn the gas back on and wait a minute for the carbs to fill with gas. If the bike doesn't start and run properly then shut off the gas and remove the carburetors from the engine.
FOR EACH carb > Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb. Remove the idle screw and the air screw on the outside throat of the carb and spray into the screw holes as well. < < READ CLOSELY > > Be sure to put these two screws back in the same hole they came out of. IMPORTANT > do not tighten these two adjusters down. Only screw these in until they LIGHTLY seat. Now turn each adjuster one and one half turns outward. Put the rest of the carb back together, clean the air filter and install the carb. Before putting the slides back in the throat of the carbs, Install an in-line fuel filter. Let the float bowl fill then start the engine. This process should get you back on the road.
Also, sync the carbs such that the slides on the carbs move at the same exact instant when the gas is slowly increased from idle speed. Please rate this solution. Thanks!
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Yea, that is way too high. Thankfully your bike is nice and old so idle adjustment is simple. Look for a knob in between the 2nd and 3rd cylinders carburetors. This should be accessible without removing any bodywork, but I'm not certain with your bike. You should set your idle to something between 1~2k rpm when the bike is fully warmed up. If your carb hasn't been serviced in awhile having it idle at 2k rpm will be more stable.
Ensure that the engine is warmed up to normal operating temperature and the enrichener knob is pushed all the way in BEFORE adjusting engine idle speed. It is possible for a properly warmed up engine to idle above the normal idle range of 950-1050 RPM with the enrichener knob pulled PARTIALLY OUT. If the bike has no tachometer attach one or attach a DIGITAL MULTIMETER equipped with an RPM INDUCTIVE PICKUP over front spark plug cable to monitor engine RPM. Then start the motorcycle engine and let it run until it reaches normal operating temperature with enrichener knob pushed fully in (enrichener closed). Then set the idle speed to 950-1050 RPM using a special CARBURETOR IDLE ADJUSTER and tip. Turn clockwise to increase idle speed and turn counterclockwise to decrease idle speed. The throttle stop screw in on the right or front side of the CV carb.
Does the bike run if you give it throttle past idle? The motor should accelerate and gain RPM's when doing so. If it does and gains RPM's but is sluggish in response, I would check to make sure it has good gas flow. Check flow off the petcock, if good, check gas filter on the motor side. If still not running correctly, I would check the air cleaner inside to make sure some critter didn't get in there and make a nest or something. Beyond those ideas, I would bring it to a profession shop or a friend in the know.
If the bike starts up and the idle speed creeps to high revs all on its' own, this indicates an air leak somewhere between the center throat of the carb and the cylinder head. This is normally a rubber seal or rubber manifold that is old, hard and cracked. I am sure the carbs need to be cleaned, remounted and adjusted. This is a nightmare for the novice mechanic. Replace all rubber fittings and seals including hose fittings and hoses.
there SHOULD be an adjuster under the seat or gastank within easy reach. Clockwise to increase rpm, ccl to decrease rpm. idle around 1400rpm when engine is at normal operating temp. Good luck!
Coming from a previous ninja owner/rider. I know adjusting the valves is a project to get the mixture just right. If you say it is running fine, I would leave it alone. It you are really looking for more power, get a jet kit which comes specific for your bike and includes a bunch of different sized jets. But my honest opinion even after reaching 20,000 miles on this bike, if it isn't broken don't change it. The best way to learn is to meet a bike mechanic and become friends with him to learn more. There are usually 3 valves that control different RPM mixtures, a low mixture knob controls RPMs from idle-6k- mid knob from 6-9 and high knob that controls the fuel-to-air mixture at high RPMs from 9-12k+ rpm's. This is just one example and they are all different. Basically you test your RPM range, adjust the knob, and repeat until you find the right feel. Too much or too little gas it will get boggy in that RPM region. Oh and don't turn the high mixture valve thinking it's the low, get a repair manual online to locate the proper knobs and you could do it yourself.
under the left side of the gas tank you will see i black knob/screw at the end of what looks like a hose. the knob faces the rear of bike. that adjusts the idle. its real easy to find and the only adjustment you can make to the carbs.
Hmmm... this doesn't sound like a problem that belongs here...
By "cuts off" do you mean stop running, or misfire?
Carb. problems often are the result of the bike having set for many months or a year or two with old gas, which can result in a varnishing like of the fuel in the carburetors, which can clogg small passage ways, and subsequent no-idle, or other poor fuel delivery. Problems such as this require repair by knowledgeable mechanics.
Other things which can upset correct fuel/air mixture are modifications such different exhaust system, air cleaner change, camshaft- any mod of these can require some retuning.