JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
Does anybody here know how to adjust one of these? I have one on my 87 Suzuki 230 Quadsport that I can't get it to want to idle very good. Any ideas? Thanks
I'm not sure on that particular model, but I used to have a Honda 250r fourtrax which might be similar. The first thing you might check is your reeds. If the reeds are shot then the fuel won't get into the piston evenly.
If the reeds are good then head to the carb. Start with the main jet. It sounds like it may be running to lean. To much air not enough fuel. Go up one size on the jet and see how that goes. I know that the jets for the honda were fairly inexpensive. 2 or 3 bucks a piece. Make sure you do all this with a good spark plug if its a 2 stroke. Also if it is a 2 stroke you make look at running a hotter plug.
Like I said I don't have experience with bike but, hopefully this will get you started in the right direction. Let us know what you find.
Deadcell,
Foulshot made some good points.
first a couple of questions. Do you have an in-line filter on the gas hose from tank to carb. If not, get one. If so, replace it. Second, Removing the carb is really easy. Though I have not worked on any suzuki's I have played with many honda's and yamaha's. Alot of times just removing the bowl and throttle neddle, and giving it a good cleaning will do wonders. If you have replaced the muffler or air filter with an aftermarket unit then you will most like need to replace the jets with larger ones ,as foulshot said,. The idle adjustment should be a small screw with a spring on the side of the carb. If you try to adjust it, make sure the bike is warmed up good before you do. Other adjustment screws on the carb are fairly easy to adjust, but you would be smart to get a manuel and do it the right way. Anyway good luck, hope this helps.
EVAN III
Well its a 4stroke not a 2 so I don't think it has any reeds.
And the folks I got it from left it setting up for about 5 or 6 years and gas in the carb had turned into varnish. It took 2 days of cleaning and soaking to get it clean. There is one big screw on the side of the carb that sticks out alot, its the idle screw. Only problem is, no matter how much I turn it in, the bike still won't idle. Or either I turn it in all the way and the bike idles at about 2000rpm. Which is way too high. I don't know what else to do. its clean as a pin inside and out. It should run good, but it just won't idle like its suppose to. I'm open to any and all suggestions at this point. Thanks
Deadcell, wanted to throw in my two cents worth.
I have just rebuilt a Suzuki LT160 Quadrunner. ON the same side of the carburetor of the idle screw is the air screw. Looking from the shifter side, you'll see the idle screws. Down and to the left is teh air screw. The air screw is kind of inset. The service manual on mine says to turn the air screw until it bottoms out and then back it out two full turns. Then adjust your idle screw. I bottomed out my idle screw and backed it out one and a half turns when initally doing it just to start somewhere. You should be able to adjust the idle screw only from that point. Hope this helps. Let me know. I am new to th forum as of tonight or would have posted earlier. Good Luck!
BigSwad, Thanks for the help and welcome to JHP!
Hope you enjoy your time here.
Thanks Foulshot! Glad to be on board. I like Jesse grew up hunting in MO and I have since moved to TX. The person I lease from out in west texas guided me to this site. We had been talking about game cameras, as I had just purchased a nontypical DC-100.
It has been working well but wanted to add another, just couldn't justify the cost. He told me about this site so here I am! Just been doing a lot of reading the past couple of days. I appreciate the warm reception and hope to join in on more discussions.
You must log in or register to reply here.
Share:
Facebook Twitter Email Share Link
Top Bottom
You are getting ready for a ride down your favorite trail.
You start the ATV, and you hear it idling higher than normal. What could be causing it, and how do you fix it?
There are many reasons an ATV may be idling high. Among these reasons are a carburetor leak, throttle cable placement, idle screw setting, clogged pilot jet, and many more. An ATV idling high should not be left unresolved. Allowing an ATV to idle too high could lead to premature wear and tear.
A higher than normal idle does not mean that you have to put an end to your day on the trails. This article will explain the reasons your ATV may be idling high and what you can do to fix it.
The carburetor is what supplies the air and fuel mixture to the engine to keep it running. If there is an issue with the carburetor, your ATV engine may be idling at a higher than normal rate.
The exact speed your ATV should idle at will depend on its age, make, and model. Newer ATVs idle somewhere between 1200 and 1700 RPMs. Check your owner’s manual to learn the exact idle speed your ATV should be at.
If the ATV is idling high, it is likely related to an issue with the carburetor.
Vacuum Leak
If the seal between the carburetor and the engine is compromised, it may be allowing extra air into the fuel mixture. This “lean” mixture can damage the engine as well as make it idle higher. A lean fuel mixture will also make for a jerkier ride than normal.
Inspect the intake system for any visible issues or damages. If there are no visible issues with the intake system, use a vacuum tester to inspect the integrity of the connections.
If you still have not located the problem, inspect the manifold and carburetor for visible problems. Ensure the vacuum sensors are not damaged. Spray water over the manifold and carburetor. If you hear the water getting sucked into the engine or the idle changes, there is probably a vacuum leak. Replace any tubes and connectors that are leaking air.
This test can be completed with carburetor cleaner as well—however, exercise caution when doing this.
Carburetor cleaner is highly flammable and if it touches a surface hot enough, it could ignite.
Clogged Pilot Jet
The pilot jet is what draws fuel into the engine when idle. If the pilot jet is clogged, not enough fuel will be mixed with the air being sent through. Like a vacuum leak, this will result in a lean fuel mixture and a high idle.
The simple solution to this problem is to clean the carburetor’s pilot jets. Because pilot jets are so small, it may be difficult to find a tool small enough for the job. While you could take it to a mechanic to get the work done, there is one trick you can try yourself: using a bread tie!
Watch this quick video to see how to make your carburetor pilot jet cleaning tool!
Cleaning your pilot jet will not require any special tools or training.
All you need is something small enough (such as a bread tie) to push out the fuel clog.
Make your bread tie into a cleaning tool, then run it through the pilot jets, reassemble the carburetor, and start up the ATV. If it continues to idle high, there may be another issue causing the idling. On the bright side, your pilot jets are now clean!
While many things could be wrong with the carburetor itself causing a high idle, it may be caused by the idle settings as well. There are two parts of the carburetor that allow you to adjust your ATV idle settings. These are the choke (throttle cable) or the idle screw.
Throttle Cable (Choke) Problems
According to an employee at Kolar Tire & Auto in Helena, MT, if the choke is stuck, it could be allowing extra air into the fuel mixture. As we already know, too much air in the engine results in a lean fuel mixture and a high idle.
Unstick the throttle cable by lubricating it with penetrating oil.
Once covered with lubricant, use a pair of pliers to move the cable up and down. Eventually, the throttle should break free and move properly on its own. Apply another layer of lubricant for good measure.
Ensure the throttle cable is set correctly. If the carburetor’s side plunger is lifted off the idle screw, it could be letting too much air in. When set correctly, the carburetor’s side plunger will sit on the idle screw.
Idle Screw
The idle screw is what determines how much air enters the fuel mixture. If you have altered the position of this screw, it may be letting too much air in. Verify the correct position of the screw by reading your ATV’s owner’s manual. Reset the screw to the correct position.
The problems described above are only some of the problems that may result in a high idle. Other reasons may be beyond your control.
The first reason your ATV engine may be idling high is a temperature change. When the weather is warm, fuel is easily vaporized and the engine does not have to do much extra work.
However, when the temperature drops to cooler levels, the fuel may thicken. This thicker fuel forces the engine to work harder to pump it, thus resulting in higher idles. Because of this factor, you may want to wait until warmer weather begins before your try to diagnose your high idling problem.
Additionally, some ATVs simply idle higher when they first start. Let the ATV run for a few minutes; eventually, the RPMs will “settle down” to normal levels. If your ATV continues to idle high, search for the problems described above.
Some other reasons your ATV may be idling high are a dirty air filter or low-quality fuel. Never leave fuel in the ATV tank for more than a month or two. If you do, the fuel may “spoil” and damage the engine. Routine maintenance, such as cleaning the air filter, can also help prevent your ATV from idling high.
It often seems like an insurmountable task for beginners to tune and adjust the carburetor of an ATV, but in fact, it is far from being the case.
Using our instructions, you can easily set up a carburetor with your own hands.
Due to incorrect carburetor settings, problems such as: acceleration dips, jerks while driving, uncertain start of the engine, poor acceleration dynamics, overheating, loss of power, increased fuel consumption, formation of deposits in the combustion chamber.
So what exactly are we going to tune?
Attention! The adjustment is carried out under the condition of a warm engine and a clean carburetor.
First, make sure there is no condensation in the carburetor. First, you need to drain the gasoline from the float chamber, for this you need to close the fuel cock and partially unscrew the screw No. 1, after the gasoline has drained from the float chamber, tighten the screw No.
1.
Let's look at photos of candles with various deposits and defects.
A 100% indicator of a correctly adjusted combustible mixture is carbon deposits on a candle.
Consider the location of the screws for adjusting the quality of the mixture and idle speed of carburetors of different models.
#1 Float chamber plug; No. 2 Mixture quality screw;
#3 Idle adjustment screw.
1 - quality adjustment screw at idle; 2 - fuel inlet fitting; 3 - fitting through which you can sleep fuel from the float chamber; 4 - screw-plug of the float chamber.
1 - ventilation tube; 2 - idle speed adjustment screw; 3 - screw for adjusting the composition of the air-fuel mixture.
ATV carburetor speed and mixture adjustment.
1. Start and warm up the engine until it reaches operating temperature.
2. Adjust the idle screw to set the idle speed to normal. Completely, until it stops, tighten the fuel mixture screw, the engine should stall. If this does not happen, check the tightness of the air supply system from the air filter.
3. Loosen the fuel mixture screw 1 turn. (Turning the screw clockwise, we enrich the mixture, unscrewing it counterclockwise, we lean).
4. Start the engine and, by adjusting the idle speed screw, set the speed slightly higher than normal
5. Slowly unscrew the fuel mixture screw until the engine reaches maximum speed (we unscrew the screw no more than 2 turns, but depending on engine wear and other malfunctions, the range may vary).
6.
Re-adjust the idle screw to set the idle speed to normal.
7. Press the throttle trigger several times, check if the idle speed is stable.
Adjustment of the mixture quality with a needle.
Probably you have heard more than once about adjusting the quality of the mixture on the carburetor by manipulating the needle. I note that these are extreme measures, for the initial adjustment, use the mixture quality screw, and only if you do not get the desired result, unscrew the mount and remove the needle. What does she represent? This is the main element that regulates the amount of gasoline supplied to the combustion chamber. Connected directly to the throttle handle through a cable. When you turn the knob, the needle rises higher, opening up a channel for fuel, thereby delivering more mixture, which increases power, which translates into speed.
You will see 5 grooves on the needle at the attachment point. Initially, the retaining ring fixes it in the central position, this is the best option.
But sometimes it is not possible to achieve the required quality of the mixture. Then we will need the remaining grooves, 2 on top and 2 on the bottom, this suggests that we can adjust the dose gradually.
Lifting the retaining ring up and locking it in this position lowers the needle, which, in turn, blocks the channel more than usual. Gasoline enters less than air, and the mixture becomes leaner. Lowering the ring down, we raise the needle, and everything happens exactly the opposite.
Be aware that an excessively lean or rich mixture can lead to serious malfunctions from overheating to loss of power, carbon deposits in the combustion chamber and all the consequences that follow from this. Keep an eye on the condition of the spark plug electrodes, this is the main indicator that will help you determine the quality of the mixture.
If you have any questions about the adjustment and tuning of the carburetor, you can ask them below in the "Comments" column.
The operation and life of the engine directly depends on the quality of the fuel mixture. The carburetor is responsible for the preparation of the composition, but after prolonged use of the equipment, the settings “go astray”. This results in:
Traction can disappear for one or several seconds. But the most unpleasant thing is that such failures occur sequentially, which significantly interferes with speed gain. Many riders who decide to buy an inexpensive ATV simply do not spare the technique and ignore this procedure. But even if you plan to change your device in 1.5-2 years, adjustment is needed. The reason for this is increased fuel consumption. A quad with an untuned carburetor "eats" 30-40% more gasoline, and these are tangible costs.
So how do you adjust the carburetor on a Chinese ATV? For this you need:
The procedure is performed using a special screw, which is responsible for the quality of the composition and the number of revolutions. However, it is important to remember that all adjustments are made only with a "clean" carburettor. This means that the rider needs to remove all the dirt from the node and flush the system to remove condensation and sediment from it.
Note: The engine must be warmed up to operating temperature immediately before adjustment.
To set the carburetor idle, the float chamber must first be cleared of fuel. To do this, start the ATV, close the fuel cock and wait until the machine stalls (5-10 minutes). To speed up the process, you can take a little ride on the quadric. Of course, gasoline can be drained, but in any case you will have to warm up the device, so the first method of "removing" gasoline is more effective.
Then:
Read the manual before adjusting the carburetor on a 125cc ATV to be sure. Remember that the location of the bolts is different in different devices, so read the documentation in advance.
To evaluate the quality of the fuel composition, make a test run. After that, unscrew the candle, and evaluate its condition. If it is:
Also look out for these “symptoms”: damaged tip (electrode failure), oil deposits (damage to rings and caps), chips and inclusions (sign of motor failure).
