gear oil on 2 stroke

vic

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Thanks nice sled you have there what is it m8 vic

Thanks M1000 . Run Premium gas on your bike ,wrong last letters heat range can foul and make hard to start seen this happen before. You can get mixing bottles with ratio's on them so you can get exact.
 
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yamaha125cc

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Thanks M1000 . Run Premium gas on your bike ,wrong last letters heat range can foul and make hard to start seen this happen before. You can get mixing bottles with ratio's on them so you can get exact.

What heat range should you be running. And are you talking about the number on the plug it self or ??
 

vic

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My 2003 honda 125 cr i run BR9EG which is recommended by dealer.My son had BR9ES in the bike and was constantly changeing them,fouling,hard to start.On the G is smaller electrode, than the S half the size.My guess is the S needs to run hotter.Contact your dealer and use what they recommend for your bike
 

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Here is a chart describing what the letters and #'s of a spark plug mean. NGK.com
You can interchange certain parameters like electrode types and heat ranges (see vic's comments above about changing the electrode type), but things like thread reach and thread diameter cannot be interchanged.

Also, resistor type plugs were invented to reduce the signal noise in radio interference in cars and trucks in the early 1960s. I have run non-inductive and non-resistor plugs in my bikes and sleds for years and never had a problem also. But the newer bikes and sleds should probably be using a resistor plug due to the increased electronics on these motors.

Quote from NGK - "Some CDIs (capacitive discharge ignition) should use a plug with an inductive type resistor (such as a NGK Z-type). Inductive resistor plugs require less voltage than a monolithic (regular) resistor plug. Use of non-inductive resistor type plugs on these motors can create an open circuit within the spark plug (it will become a dead plug)."
 
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No, I've never fouled a plug. I do change them every season though, and I also use a couple tricks like indexing and a ground electrode split to get better flame kernel exposure.

It's not all in the jetting and running a hotter plug is not a band aid fix, it's the reason they make hotter or colder plugs, to maximize power out of your motor be achieving perfect combustion temperature. Yes you need to be close with your jetting, and then you can tweak it with the plug and achieve a better result in the end. This is not understood by many people. Plug heat range and jetting are two very different motor issues, one can exist without the other. Jetting is related to the air/fuel ratio and at what temp that mixture burns in the cylinder. Plug range temp relates to ignition temp, vapourization temp of the fuel you are using, plug temp, how much carbon is burnt off the plug, etc, etc. Jetting has more to do with altitude and air density than just the weather. Jetting is only a portion of the equation, if you think that you can make a bike run perfect on 15:1 fuel/oil with custom jetting, you can go ahead and try - I'll be riding while you try and figure out why your bike won't run. Too much oil in the fuel and not a hot enough plug will result in incomplete mixture burn (vapourization) and cause too much deposition on the plug, resulting in fouling of the plug. So you can cut back the oil (if you are at 40:1 already - bad idea IMO), or you can jet leaner or you can run a slightly hotter plug and jet slightly fatter for a margin of safety.

I jet lean and run one hotter range plug, never, ever fouled a plug, I mix at 32:1 and my pyro's run about 1320 on a long steady pull. I can gain or lose 50 degrees just by changing the plug heat range, once it is fine tuned with jetting. My oil ratio never changes, but I could foul my bike out with too much oil and a cold plug if I wanted to. :)



Preventing Fouling:
So you’re probably asking yourself, why are my spark plugs fouling? The answer is simple.
Snowmobile manufacturers tend to jet carburetors on the rich side as a safety factor in order to prevent engine damage and warranty claims. In addition, manufacturers have to consider changes in temperature and elevation. Snowmobile engines are for the most part two-stroke, carbureted engines. Unlike fuel injection systems, carburetors can’t compensate for changes in humidity, ambient temperatures and elevation. Therefore it’s up to the consumer to make sure carburetors are jetted and synchronized correctly. Yes jetting can be a pain, however, jetted correctly a spark plug should last the whole season.
Carburetor jetting is quite simple and easy to learn. Many carburetor manufacturers have jetting charts located on their websites. Take the time to review these charts and learn how to jet properly. If you’re uncomfortable jetting and synchronizing your carburetors we highly recommend taking your snowmobile to a trained professional. An important thing to consider is your technician can only jet for the conditions in your area. If you plan on traveling outside your area to a place with higher elevation and different ambient temperatures the tune-up will most likely be incorrect for the location you’re planning to ride. In this case re-jetting may be required.
Hotter Spark Plugs:
Many snowmobile enthusiasts believe the spark plug is the root cause of spark plug fouling. Again, spark plug fouling occurs as a result of incorrect carburetor jetting. A bandage approach to fix a fouling issue is to install a hotter spark plug. This can, in some cases fix the problem however this only masks the real problem which is fuel delivery.
A snowmobile can be rich or lean at idle, mid and wide open throttle depending on how it’s jetted. A properly tuned carburetor should supply the correct amount of air/fuel throughout the entire power band. A hotter spark plug may temporarily fix the problem however under certain lean conditions be too hot. Under these conditions pre-ignition can occur resulting in insulator failure and extensive engine damage. Fix it right the first time and you will save yourself time and money.
 

yamaha125cc

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Preventing Fouling:
So you’re probably asking yourself, why are my spark plugs fouling? The answer is simple.
Snowmobile manufacturers tend to jet carburetors on the rich side as a safety factor in order to prevent engine damage and warranty claims. In addition, manufacturers have to consider changes in temperature and elevation. Snowmobile engines are for the most part two-stroke, carbureted engines. Unlike fuel injection systems, carburetors can’t compensate for changes in humidity, ambient temperatures and elevation. Therefore it’s up to the consumer to make sure carburetors are jetted and synchronized correctly. Yes jetting can be a pain, however, jetted correctly a spark plug should last the whole season.
Carburetor jetting is quite simple and easy to learn. Many carburetor manufacturers have jetting charts located on their websites. Take the time to review these charts and learn how to jet properly. If you’re uncomfortable jetting and synchronizing your carburetors we highly recommend taking your snowmobile to a trained professional. An important thing to consider is your technician can only jet for the conditions in your area. If you plan on traveling outside your area to a place with higher elevation and different ambient temperatures the tune-up will most likely be incorrect for the location you’re planning to ride. In this case re-jetting may be required.
Hotter Spark Plugs:
Many snowmobile enthusiasts believe the spark plug is the root cause of spark plug fouling. Again, spark plug fouling occurs as a result of incorrect carburetor jetting. A bandage approach to fix a fouling issue is to install a hotter spark plug. This can, in some cases fix the problem however this only masks the real problem which is fuel delivery.
A snowmobile can be rich or lean at idle, mid and wide open throttle depending on how it’s jetted. A properly tuned carburetor should supply the correct amount of air/fuel throughout the entire power band. A hotter spark plug may temporarily fix the problem however under certain lean conditions be too hot. Under these conditions pre-ignition can occur resulting in insulator failure and extensive engine damage. Fix it right the first time and you will save yourself time and money.


You do know we are talking aabout dirt bikes and not snowmobiles right?
 

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Preventing Fouling:
So you’re probably asking yourself, why are my spark plugs fouling? The answer is simple.blah blah blah.

I get it that you can foul a plug with improper jetting, I've never disagreed with that. Fouling a plug in other ways is also possible, but I'm done explaining them to you.

You can keep regurgitating articles or threads you've read on other sites, I don't care honestly. If I wanted to read cookie cutter engine theory that you can learn from wikipedia, I'd search google myself. Running a hotter range spark plug is not a band aid solution for anything, and often times, saying something along those lines means there is a lack of understanding, IMO. Can it be used as a band aid solution for incorrect jetting? - yes. Is that what anyone has proposed here? - no. We were talking about oil fouling with too much of a ratio, however your opinion is that spark plugs only foul out due to jetting, not oil. I'm not sure if this is based on internet research or what, but I know from experience there are other ways to foul a plug.

But maybe I'm just some stupid fool from Podunkville who has incredible spark plug luck and actually doesn't know anything about this topic. Here's a pic of my current ride - wanna know if it's jetted correctly and if it fouls plugs? :rolleyes:
 

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yamaha125cc

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I get it that you can foul a plug with improper jetting, I've never disagreed with that. Fouling a plug in other ways is also possible, but I'm done explaining them to you.

You can keep regurgitating articles or threads you've read on other sites, I don't care honestly. If I wanted to read cookie cutter engine theory that you can learn from wikipedia, I'd search google myself. Running a hotter range spark plug is not a band aid solution for anything, and often times, saying something along those lines means there is a lack of understanding, IMO. Can it be used as a band aid solution for incorrect jetting? - yes. Is that what anyone has proposed here? - no. We were talking about oil fouling with too much of a ratio, however your opinion is that spark plugs only foul out due to jetting, not oil. I'm not sure if this is based on internet research or what, but I know from experience there are other ways to foul a plug.

But maybe I'm just some stupid fool from Podunkville who has incredible spark plug luck and actually doesn't know anything about this topic. Here's a pic of my current ride - wanna know if it's jetted correctly and if it fouls plugs? :rolleyes:



nice ride what kind of motor is that. Twin something. Gasoiline or nytro stuff
 

Modman

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nice ride what kind of motor is that. Twin something. Gasoiline or nytro stuff

In-line 4 cylinder street bike motor. ..... it runs on a mixture of things.....mainly race fuel.

I would say a twin/ twin. :d

Modman- what's your yearly chain budget for that thing??

Chain's cheap. :).......compared to tires... It eats tires like crazy - the one in the photo is an experiment and probably ain't going to last long, I think its too soft, will probably have to bolt it. i have another supplier out of the states that makes a much harder pre-moulded paddle tire, I order them 2 at a time...but after shipping, exchange and duty they work out to be about $135/tire.
 
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I get it that you can foul a plug with improper jetting, I've never disagreed with that. Fouling a plug in other ways is also possible, but I'm done explaining them to you.



How have you explained any thing other then heat range. How many plugs are fouled because of heat range... maybe 1%. How about float height, air filter,old fuel,and riding style(all things you check when jetting) Your plugs Heat range is about getting the most hp out of an engine and is one of the last step in fine tuning. To tell a person to use a hotter plug could work....But with the oils they have these days to have a plug foul at 32:1 is not the heat range of the plug... you don't need a better burn off, you need a better burn (air/fuel). and it's the same with a 4-stroke. But you know this
 

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How have you explained any thing other then heat range. How many plugs are fouled because of heat range... maybe 1%. How about float height, air filter,old fuel,and riding style(all things you check when jetting) Your plugs Heat range is about getting the most hp out of an engine and is one of the last step in fine tuning. To tell a person to use a hotter plug could work....But with the oils they have these days to have a plug foul at 32:1 is not the heat range of the plug... you don't need a better burn off, you need a better burn (air/fuel). and it's the same with a 4-stroke. But you know this

I've even quoted myself to help you. No one said plugs foul because of the incorrect heat range....The difference in heat ranges of plugs are about 450 degrees at the ignition point. If you are cooling the plug with too much fuel or too much residual oil, it's going to foul.
.......

A plug fouls for one of two reasons - the plug is too cold,..... If your plug is fouled and it's not debris, then the plug is too cold to burn an effective spark from center to ground electrode, whether it was cooled by excess fuel (jetting too rich) or excess oil in the fuel (mix ratio too rich).

We are not talking about 32:1, we are talking about 10:1, as posted by jw_0 on page 1 and as commented on by KTM13-44. You seem determined that you can only foul a plug by being too fat on the carb, yes at 32:1 you would be fouling due to jetting likely, but at 10:1 you'll likely be fouling from oil, I'm telling you I've fouled plugs with too much oil in the fuel, but you don't want to believe me. So go mix a tank of 10:1, start riding and see what happens, I could care less if you do or don't. Honestly, I don't care what people read on the internet about engine theory because I'm talking from experience, which is what I'm trying to pass along. I've built motors for almost 15 years and jetted everything from lawnmowers to 1000+ HP alcohol big blocks. I know that heat ranges are used to fine tune motor parameters, because I already said it in a post above!

If you want to get into it though, here's my layman's version. You get it as close as possible with the jetting you are comfortable with and then you add a slight safety margin so that you don't burn down your motor. If you are a good mechanic and don't mind re-building your bike 10 times a season then you jet right on the edge and hope for the best. If you jet to the safety margin (not on the lean edge), then you can use a different heat range of plug to tweak the combustion temp, with less risk of burning a hole in the top of your piston and maybe squeeze just a little more jam out of it. Sometimes a hotter plug will help, sometimes it won't, but for $3, at least you tried. Even with all this, if you dump 15:1 in your motor your plug will foul, correct jetting or not. Where in the RPM band will your motor foul this plug? after prolonged idling or low speed running because the combustion temp will not be sufficiently high enough to burn residual oil off the plug. At WOT it will likely not foul or take longer to foul because the increased combustion temp of faster engine cycles will help to mitigate this.
 
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Ok no ones talking about 10:1 or 15:1, they seem to be running 32:1 to 40:1. and you know were talking about dirtbikes? they don't want to do dyno runs, they just want to know why his bike eats plugs, If you know how jetting/carb works then you can see things in a different light. I'm just saying 32:1 not the reason.



And maybe I'm just some stupid Army mechanic that has his tickets
Oh here's my ride in Afghanistan...maybe you want to rebuild it's 1500hp V12 diesel engine?
 

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Modman

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The reason you're fouling plugs has nothing to do with how you mix your oil.

Yup i always ran 40:1 with ams sythetic and 10-40 in the clutch never had a problem mixed the bike up oncne at 30:1 with a cheaper oil and kept fouling the plug.

False - trying running your bike at 15:1 with perfect jetting - see what happens. :d

Ok no ones talking about 10:1 or 15:1.......... I'm just saying 32:1 not the reason.

And maybe I'm just some stupid Army mechanic that has his tickets
Oh here's my ride in Afghanistan...maybe you want to rebuild it's 1500hp V12 diesel engine?

No 32:1 is likely not the reason, but if you run 15:1 it could be, which was what I was talking about on page 1 (See above). I never said you were stupid.

That's a sweet ride! I'd joke with you if it fouls plugs but I already know the answer...LOL

And thanks for serving.
 
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