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Fouling plugs on Husqvarna TE610 (fuel injected)

I am riding in high elevations and I keep fouling plugs. I have had to change out twice in one ride. I am cleaning the air filter now. My bike is fuel injected so it can't be a jetting problem. Any more suggestions?

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  • Motorcycles Master
  • 17,093 Answers

This is an issue that has to be taken care of with reprogramming the ECM.

Posted on Jul 24, 2013


6 Suggested Answers

  • 2 Answers

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Posted on Jan 02, 2017

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SOURCE: i keep fouling my plug on my 03 rm85. oil/fuel mix is right

what color is the spark plug when you take it out? All black too rich, a chalky white look is way too lean which is far worse than a rich mixture. I blew up my CR-80 when I was a kid from an improper fuel mixture. You really have to get that correct and the dealer can give you the numbers on that. Also you might wanna get a measuring cup from a local dollar store or discount store to help you add the correct mix into the gas. You said its boggy in 1st and is it from 3rd up? Has the carb been jetted for possibly a different exhaust pipe or filter that aren't on the bike anymore? Or did you change those components and not jet correctly? I'm going to log this as a solution, but its borderline a clarification request....

Posted on Apr 05, 2009

  • 867 Answers

SOURCE: Running on three cylinders, fueling up plug!

if three cylenders are running fine and 1 not with a wet plug, something is wrong with the one cable , its connection, shorting(make sure its not to close to the engine) or the plug

Posted on Jun 21, 2009

  • 194 Answers

SOURCE: my bike keeps fouling my plugs i got a 2003 yamaha

Two things could be at fault here. First - it's a good possibility you would benefit from a new top end. Top ends go away fast in these because they are single ringers. Under hard riding, the compression starts to fall off after just 2 hours. Poor compression means lower combustion temperatures which will lead the bike to run rich.

The other possibility is that your jetting is off. If you have had this bike for a while and it's always run well then slowly started to act up, its likely poor compression, but if you recently got this bike and do not know the history of it, then it could be a simple jetting issue - not at all uncommon for 2-strokes.

Also - no need to run the BR8EG. This is a resistor plug and is a higher performance plug. If you are a top Pro rider, you could feel the difference but for 99% of riders they could not tell the difference between a BR8EG and a B8ES. The B8ES is readily available from auto parts stores (NGK stock #2411) for $1.89 instead of $12+ for a EG plug form a bike shop. This info alone could save you a bunch of money. Keep in mind the stock plug is BR9EG, so you are running one step hotter which is fine.

Also keep in mind there is a lot of information that I do not know, nor do I know the overall condition of the bike. Internet diagnosis is always tricky, but I thought I would point these things out. I hope this has helped, but if not - we need more detailed info to properly diagnose the problem.

Posted on Feb 09, 2010

  • 440 Answers

SOURCE: I have 93 katana 750 I bought off craighs list 4

Rather the opposite, the engine is not getting hot enough to burn off the carbon deposits.
If all plugs are fouling it is probably not enough air in the mix
1st check your air filter is clean
2nd check air screw settings are 1-5/8 turns out
3rd check that main jets are 105s

Hope this helps(if so please mark as very useful)
Ride Safe

Posted on Apr 16, 2010

  • 3567 Answers

SOURCE: We keep fouling spark plugs.

Several ways to try. Be sure the air filter is clean and without any tears or punctures, install an in-line fuel filter, gap the spark plug at .030, be sure the stock spark plug is used ( NGK CR7HSA ), be sure the muffler not plugged up at all, increase the idle speed, and change the gearbox oil every 2 or 3 months. The only other thing would be to de-carbon the piston and head but that requires the head to be removed. Taking the head off isn't hard but you must be sure to have the valve cam timed properly when reassembled. If not installed properly, you can bend a valve the first time you try to kickstart. Please rate my answer.

Posted on Jul 12, 2011

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125 Pitbike keeps fouling spark plugs

Hi, Damon and the usual suspects are:
1. Dirty air filter.
2. Fuel mixture too rich or the choke has been left on too long.
3. Faulty spark plug.
4. Incorrect spark plug heat range for the engine type or service.
5. Piston rings badly worn or broken.
6. Valve guides are badly worn and/or seals worn, crushed or have come off the valve guide and are pumping oil through it.
7. Spark plug cable weak or leaking check for spark leakage in the dark.
8. Faulty ignition coil.
9. Low RPM nonaggressive riding style.
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Spark Plugs Fouling

this might b out of price range but new carbs and electronic ignition will still have to tune also, or get the carbs ultrasonic cleaned then set up to factory specs will be a good starting point

Feb 04, 2014 | 1978 Ducati 900 SD Darmah

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Why does my dirt bike keep fouling plugs

Hi, Joey assuming it's a 2 stroke the usual suspects are:
1. The first thing to do if your spark plug has been fouled is to check the air filter. If it's really dirty, that makes it difficult for air to get through to the engine, causing a rich condition. Either clean it thoroughly with some Air Filter Cleaner or buy a new filter. Before you put it back in the air-box, treat with a fine mist of some air filter oil or spray. "WARNING" adding too much oil can also clog up the filter, resulting in another fouled plug.
2. While the gas/oil ratio doesn't equate to what the jetting is, you can still foul plugs, or worse, if the mixture is wrong. Depending on your bike, it's best to look at your owner's manual for the correct ratio. For most 2-stroke motocross bikes, a ratio is 32:1 or 40:1, the gas being 32 or 40, and oil being 1. For those that don't it, it means that for every 128 ounces (one gallon) of gas, you add 4 ounces of 2-stroke oil for a 32:1 ration, or just over 3 ounces for a 40:1 ratio.
If you have too much oil in the mixture (such as 12:1), then you will probably end up fouling the plug because it is more difficult to burn that much oil. Don't try to cut corners with the oil though, because it's very important for your dirt bike's engine. 2-stokes need the oil for lubrication on the cylinder walls, so if you don't have enough (or any for that matter) then the cylinder walls will run dry, causing it to overheat and seize the engine very quickly. So it's very important that you put in the right mixture pre-mix to your 2-stroke gas tank.
Also, 2-strokes have reeds that air and fuel go through into the cylinder, so if they are cracked or broken the bike will not run right. This could cause the plug to foul, so before you go out and buy anything expensive, make sure the reeds are in good condition.
3. While this usually isn't the main problem, it could be that your spark plug isn't burning hot enough. Having a hotter spark will ignite the fuel stronger, leaving less residual gas/oil in the cylinder that could cause the plug to foul. This "ISN'T" the best choice, but I'd say it's safe to go one plug hotter than stock. Keep an eye on the plug color you're looking for a light tan color anything whiter and you could burn a hole in your piston. Spark plug manufacturers aren't always the same, so make sure you find out how they rate them.
4. Almost every motocross bike comes rich from the factory (especially Honda 2-Strokes when they were being made). It's usually a pretty simple fix, but many riders are too lazy and would rather continue buying plugs instead of spending a few bucks on jets.
5. Piston rings badly worn or broken.
6. Faulty ignition coil low output.
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1 Answer

2006 gsxr has 1 cylinder that keeps fouling the plug

if its injected u may have a stuck injecter if so take it out use a 12 volt battery and pulse the injector in a cleaner or high octane fuel. 108 oct or up

Mar 04, 2013 | 2006 Suzuki GSX-R 1000

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Our Husqvarna YTH2148 mower has been in the shop twice and we can't figure out what's causing black, sooty fouling of the spark plugs.

Hi, change the engine oil. It has become contaminated with fuel. Also fit an inline fuel tap and turn it off whenever the mower is not in use. Basically the carby has leaked fuel into the engine oil, the engine then draws the fuel vapour from the oil through the crankcase vent into the carby creating the problem you have. Regards Phil.

Jun 03, 2012 | Husqvarna Garden

1 Answer

95 GMC 5.7l keeps fouling plugs

Hi Dale,

Several factors can contribute to spark plug fouling:

- The air/fuel ratio may be too rich as a result of incorrect carburetor adjustment or a poorly performing fuel injection system.
- Worn piston rings or valve seals may allow too much oil to leak into the combustion chamber, leading to oil fouling.
- The ignition system may not be performing properly.
- Prolonged idling or continuous low-speed driving may keep the spark plug from reaching its optimum operating temperature. Using too cold a spark plug can lead to the same problem.
- A dirty air cleaner can create a too-rich condition which can lead to fouling.

Have each of the above checked and corrected.

Fuel, oil and carbon fouling can all be the result of different causes but, once a spark plug is fouled, it will not provide adequate voltage to the firing tip and that cylinder will not fire properly.

In many cases, the spark plug cannot be cleaned sufficiently to restore normal operation. Hence, I always recommend that a plug be replace, once it becomes fouled.



"If this has helped you in any way, please be kind enough to rate this solution"

Nov 02, 2011 | 1995 Chevrolet K1500

2 Answers

What spark plug should i run in my 2003 YZ 125?

Run a B9ES if you don't have a problem with fouling. If you do have a problem fouling, run a B8ES. Both of these plugs are available at auto parts stores for a few bucks each.

The stock plug was a BR9** - the R indicates a resistor plug which is not needed.


Jun 18, 2010 | 2003 Yamaha YZ 125

1 Answer

One plug is constantly fouling

If you're running the correct spark plug, you need to determine what is fouling the plug. Is it gas fouling or oil fouling? If it's gas fouling, what type of fuel delivery system is on the bike, carburator or fuel injection? If it's oil fouling, there could be a broken ring in that cylinder or a bad valve guide or seal.

Oct 15, 2009 | 2003 Harley Davidson FXDL Dyna Low Rider

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