Question about ATK 125 2-stroke Motorcycles

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I have a 1991 ATK 406 dirt bike I have changed all the fuel and cleaned all fuel lines I have also looked up proper fuel and oil mixters also I'v put new sprark plug and new air filter. Its got a very exspensive exguast pipe and many high quality performance parts. But everytime i have taking this bike out to ride it does not performe like it should.. It will start very easy usually on the first two kicks and revs up very good and sounds amazing! But once in gear it runs very very sluggish and will not rapp out like it should and sometimes will just quit running all together while in gear and on the move... So i restart it and it'll take off like no other and runs really good for bout 3 minuts then starts spittin and sputterin all over again... This bike was givin to me and belonged to a very mechanically inclined person who took good care of it.. I know alot and can repair most stuff but i'v done just bout everythings i know of to diagnose the problem....

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Hi, Cody the following applies to carbureted also fuel injected models and the usual suspects are:
1. Severely discharged or a damaged battery, 9 volts or lower.
2. Faulty alternator/generator and or voltage regulator.
3. Check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
4. Faulty main circuit breaker or ignition switch, check for loose connections and continuity.
5. Faulty system and or ignition relay, check for continuity.
6. Faulty ignition coil, ignition/electronic module.
7. Faulty CKP, CPS, CMP, MAP, TPS, O2, or BAS sensor, corroded, loose or broken wire connector pins/sockets.
8. Water or dirt in the fuel system, carburetor or filter.
9. . Restricted, blocked or kinked fuel line.
10. Fuel tank empty.
11. The gas cap is not venting properly or fuel tank venting system blocked.
12. A faulty Fuel Pump, pressure regulator and or fuel injectors.
13. Vacuum line from intake manifold to petcock broken, cracked, or not attached, carburetor vent line plugged.
14. Needle and seat stuck closed in the float bowl.
For more information about your issue, please visit the websites below. Good luck and have nice a day.

Posted on Oct 31, 2015


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Posted on Jan 02, 2017

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SOURCE: My 2006 electric glide a 1300 has been runnin bad

The most likely cause is moisture trapped inside the spark plug caps. Slide each one off of its spark plug, then spray inside the cap with WD-40. Do the same for the end of the spark plug where the cap goes on. Remove the excess WD-40 with a clean paper towel. WD-40 is non-conductive and will remove the moisture (which is highly conductive).

Posted on Nov 27, 2009

  • 2702 Answers

SOURCE: I have a 1991 rotax ATK 406 dirt bike and won't run right

check the engine compreshion,,is it low??????
check the air filter is clear the engine needs to breath,,,
check your getting full throtol,,,silly i know,,but?
check that the carb is not flooding and that no jets are blocked up,
check there is a good flow of fule from the fule tank to the carb,
check the ingition timing is spot on,,if its out ,,,fix it!
change the spark plug,, for the right plug!
check that nothing is draging,,like brakes! or slipping like clutch?
if the gear box it partly sezed up,,its going to be hard to turn the rear wheel when in gear with the clutch pulled in,,,
hope this is of help to you...

Posted on Jul 12, 2010

Testimonial: "Hey thanks mike your a smart dude! I did notice however after draining the crank case and gear box of its old oil I refilled it with new oil... Anyway I put it in gear and and pulled in the clutch it was a little tough to move the rear wheel so does this mean i have a seized gear or the clutch just might need to be adjusted. I really was hoping it wasn't gonna be this problem its like the last thing i really wanna work on with this bike but i think this is prolly the problem..."

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2007 ATK dirt bike no spark

Hi, Ken and the usual suspects are:
1. Fouled spark plugs.
2. Severely discharged or a damaged battery, should have 12.5 volts or better and be able to pass a load test if necessary.
3. Check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
4. Loose connection at ignition coil or plug between ignition sensor and CDI box.
5. Spark plug cables in bad condition, shorting / leaking, spark plug cable connections loose, check for spark leakage in the dark.
6. Faulty ignition coil, pick up coil, trigger coil or CDI box testing needs to be checked with an ohmmeter at 70 degrees Fahrenheit
7. Faulty safety switches clutch, kickstand, neutral, off/on etc.
8. Faulty ignition switch.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
ATK Rider Forum View topic 260 is getting no spark
How to fix No Spark Problem on Motorcycles and Dirt Bikes
ATK Rider Forum View topic No Spark 2000 ATK 250LQ questions and...
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Nov 12, 2016 | ATK Motorcycles

1 Answer

110cc suzki wont stay idling

Hi, Mark and the usual suspects are:
1. Idle circuit and transfer ports clogged.
2. Air fuel mixture adjustment too lean.
3. Pilot jet clogged.
4. Faulty accelerator pump.
5. Float level too low.
6. Float bowl contaminated old fuel, water, dirt, rust, etc.
7. Float bowl vent or overflow tube clogged.
8. Fuel flow to carburetor restricted.
9. Intake manifold leak.
10. The gas cap is not venting properly or fuel tank venting system blocked.
11. Vacuum line from intake manifold to petcock broken, cracked, or not attached, carburetor vent line plugged.
12. Needle and seat stuck closed in the float bowl.
13. Multi carburetors not in sync.
For more information about your issue and valuable "FREE" downloads that you will need please click on the blue links below. Good luck and have a wonderful day.
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How to fix dirt bike that wont idle
Kawasaki KLX110 Service Manual
OEM parts for Suzuki

Jun 12, 2017 | Suzuki Motorcycles

1 Answer

1980 Yamaha XS 400 Special First, How do you tell if it has an electronic ignition? Second, Can't get it to start. Have put gas in spark plug holes. Didn't hit. Bike has been setting on a dirt...

First, you need a good battery. The bike does have electronic ignition. Soak the carbs in denatured alcohol for two hours after removing the float bowls, then clean with spray cleaner. Spray into every large and small hole you can find. Remove the rubber diaphragm from the center of carb prior to cleaning. New diaphragms are $196 each. Check all fuses. Put in new spark plugs, NGK-BP7ES. Clean the air filter. Get a can of spray starter fluid and spray on the air filter. The rubber mounts for the carbs are likely to be a problem once it gets running. It looks like they are still available at Babbitt's, $53 each. If un-carburetored air can get into the joints it will lean the fuel mix and cause uncontrollable high idle.

Before you sink a lot of money into the bike, check for spark. If spark is present, coast the bike down a good sized hill without any spark plugs being installed. Put the bike in 3rd gear as you go downhill then let the clutch out to turn the engine over. Now ( using the clutch lever ), shift through all the gears then neutral. If the bike will not shift properly it likely has a bent shift fork. I can't find any forks avaiable. With a bad tranny I would put it back in the dirt floor building and find a newer bike. Here is a link to Babbitt's. Please rate my answer. Thanks.

Aug 13, 2010 | 1980 Yamaha XS 400 Special

2 Answers

I have a 1991 rotax ATK 406 dirt bike and won't run right

try cleaning the fuel filter, it may be as simple as that

Jul 12, 2010 | ATK 125 2-stroke Motorcycles

1 Answer

Bad fuel milage!.

Perform fuel injector check, check the Air filter, clean MAF sensor with the MAF sensor cleaner.Dirt sometimes accumulate on the sensor and that could cause for poor mileage.Before changing your engine oil
clean fuel injectors and sludge from the engine using 3 oz pure acetone and 2 oz xylene on 10 gallons of the fuel. Drive vehicle and then change your oil. You will notice a lot of sludge coming out of the pan. After draining oil, remove pan and gasket and clean with solvents and dry with the compressed air. DO NOT clean with the rag because that can contaminate your engine and oil.

Feb 21, 2010 | 1991 Ford F150

1 Answer

My atk 450mx stalls often

clutch cable needs adjusting its still engaging whilst when you stop by sounds get back to me if its wrong i have other optons

Oct 12, 2009 | 2005 ATK 450 Mx

2 Answers

Kawasaki gpz 1000 rx 1987 model

Running well at high revs would indicate that all the fuel and air it needs are getting to the engine and you also have a good spark. Probably no problem with air and fuel filter ( if fitted) or sparkplugs.

Running hot, and bad idling are signs of a lean air fuel mixture. The engine is probably not getting enough fuel at low revs.

This could be caused by an air leak between the carburettors and the engine. Check that the vacuum line to the fuel tap is properly secured at both ends. It is behind the fuel line at the tap.

Get a a short length of hollow plastic tube and use it like a stethascope - put one end to your ear and move the other end around your carburettor mounts with your engine revs as low as you can get, and listen for any sucking noises that would indicate a leak. Look for cracks in the rubber inlets.

The other possibility is that there is an internal blockage in the idling jets or idling fuel circuit. This is where dirt tends to lodge because the jet dimensions and passageways are very fine - The high speed jets are much bigger and dirt often just passes straight through.

Try a little bit of choke while the engine is warm to see if you get a stronger low speed response. If so that would point to an internal blockage.

Jan 24, 2009 | 1987 kawasaki GPz 1000 RX

1 Answer

Fuel leak

Wait... fuel is pouring out of the crankcase breather? Are you sure it's not the carb overflow tube? The crankcase breather should be going back into your airbox or through some kind of filter. If gas is coming out of there DO NOT START YOUR BIKE. It means that gas has gone from the tank through the carbs into the cylinder and is now in your oil. Thinned out oil is the devil for bikes. Sounds like you'll need to clean the carbs and set the float bowl height and maybe rebuild the petcock. Check to see if any fuel is coming out when the petcock is turned off. If it only has on pri and reserve then check for gas in the vaccum tube.,,

Nov 10, 2008 | 2003 ATK 605

1 Answer

No spark

I have inspected the engine oil filter and found very little two sections of the filter showed a little metal but not really more than you would expect from a newly broken in bike . The fuel pump continues to run at all times I disconnected the fuel pump removed the plug and checked it for spark: no dice. The 10 amp fuse in the back is fine, I assume that is the one and only fuse on the bike. ' Is it safe to assume that my bike has no spark (and fuel pump runs constantly) because the ECU is toast? I did not check for power from the magneto or check the pulse generator out yet....i guess i just assumed the ecu was junk where can I get the part?,Best to find someone nearby with a D&M kit to test your ECU for communication. If no one is available, your ECU can be sent to Canniboomer to be checked for proper function. If it fails, then he can send a new or possibly a used replacement. Don't forget the Diode update is likely necessary on your bike. ,,,

Nov 10, 2008 | 2003 ATK 500

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