Oil for your ATV
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03-24-2008, 11:17 PM
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Oil for your ATV
Rather than add this to the ongoing topic of what oil do you run in your ATV I though it better to start a new topic and not have it get lost to soon:
thought this was interesting. i know alot of you already know this but i figured for anyone wondering why they cant use regular oil in there atvs. ill put the link because theres more info on the page but ill post the artcle as well.
http://www.bikenomads.com/wiki...p/D...ar_oil_in_bikes
Car oils in Bikes ?
A lot of people have used engine oils meant for cars in their bikes and claim that there is absolutely nothing wrong in doing so since they cannot find any damage .
The damage is certainly not perceptible to you , but such engine oils undoubtedly damage the internals . A brief intro for those who don't want to read the lengthy post-
Most car oils are rated as API SF, SG, SL and the latest being SM (not yet avail in India)
These ratings are given once in three years and each new rating is an improvement over the previous one . The ratings are in the same order as the english aphabets . The newer is better . so SM is better than SL and SL is better than SG etc.
Car engine oils have friction modifiers in them . Motorbike engine oils - specifically four stroke engines with a wet clutch multiplate setup do not require oils with friction modifiers . Modifiers can increase or decrease the friction , but most of the modifiers used are to reduce friction.
In my earlier post wrt to synth oils I have already explained why synthetic oils sometimes cause the clutch to slip .
[edit]Recap - Synthetic Oils
Recap - synth oils meant for cars when used in bike will cause clutch to slip because car synth oils have friction reducers which are not requried in wet clutch motorbikes. The oil in wet clutch motorbikes need the oil only as a coolant not a lubricant . The lubing is required for the engine and not the clutch in this case. Hence use only specially formulated motorbike syth oils and not mobil 1 etc in bikes. Synth oils are available for mobikes specifically - ex motul 300V.
[edit]Bike spec oils
coming back - The SL and SM ratings have friction reduction modifiers which are required in cars but for the same reason as explained above, they are not suitable for wet clutch multiplates . Apart from the clutch it is reported to cause damage to engine as well . The links for all of this is given below.
The only API ratings that are applicable to most indian motobike engines are oils that are of API SF or SG ratings . Check any bike manual and most of them are of this specification .
The only body which is rates oils for use in 4stroke wet clutch bikes is JASO - Japanese Automotives Standards Organisation (http://www.jsae.or.jp/e07pub/jaso_e.html) . There are two ratings from JASO - MA and MB . MA for hi friction engines and MB for low friction engines . MB is never recommened for any indian bike . As explained previously its for low friction application - not for our kind of bikes.
Always use JASO MA grade oil . It doesnt matter what the API rating is , if its JASO MA - you are guaranteed that the clutch won't slip and as long as the oil is not API SL and above you are guaranteed that the oil is not harming the engine. All the relevant links are given below.
[edit]Resarch from the Net
From http://www.sportrider.com/tech/146_0308_oil/
Rather than continue to rely on specifications dedicated to automobiles, the Japanese Automotive Standards Organization (or JASO) developed its own set of tests specifically for motorcycles. JASO now publishes these standards, and any oil company can label its products under this designation after passing the proper tests. JASO offers two levels of certification, MA (high friction applications) and MB (low friction applications). JASO requires that the entire product label be approved before it can carry its label. If a label does not have a box with a registration number above the MA or MB lettering, it could be nonapproved oil whose manufacturer claims its products meet JASO standards when it may not have actually passed the tests.
These standards also include a test specifically designed to measure the oil's effect on clutch lock-up, as well as heat stability and several other factors related to motorcycle engines. Our advice here is pretty simple: Read your manual, and if it calls for an API SG oil, use that. Don't substitute a higher API designation oil like SL, because it will contain less of some additives like phosphorus, and it may contain other additives that will yield higher fuel economy in a car but could cause slippage in your clutch. (More on that later.)
[edit]Why should you not use car engine oil in bikes
http://www.math.uwaterloo.ca/~...nder/oil_opinion.html
None of the arguments I've provided so far have relied on the familiar old ideas about motorcycle engines being harder on oil than car engines that are so contentious in the debate. What I've presented so far is sufficient to show why you should not use modern typical car oil in typical motorcycles. But let's at least mention some of the old reasons.
Zinc from ZDDP. Zinc is an anti-wear additive typically found in motorcycle-specific oils at higher levels than in car oils. The chemical that provides it is ZDDP, zinc dialkyl dithiophosphate.
Phosphorus from ZDDP. This ingredient is helpful for preventing gear wear. It is used in motorcycle engine oils to help protect the transmission. But phosphorus is bad for catalytic converters, so car oils, which are not used to lubricate transmission gears, have very little phosphorus.
Viscosity. The common car oils are 10W30 or lighter, like 5W30 and 0W30. These are too thin for motorcycles. Most motorcycles call for 10W40 or heavier in order to support bearings, resist against consumption due to volatility, and so on.
The debate over factors such as these often revolves around questions of the degree to which your engine actually experiences the extreme conditions that specialized formulations are intended to protect against, the degree to which simple use of ordinary oil with a much higher frequency of replacement would offer similar protection, and the relatively high cost of motorcycle-specific oils.
Anectodal stories abound, but as single data points, they're not worth much. When the motorcycle manufacturers themselves, who have no vested interest in whose oil you buy, warn against the use of car oil for specific reasons, and when the oil industry itself acknowledges this difference in requirements by responding with a new set of standards for motorcycle-specific oils, I think it is pretty safe to put your trust in the recommendation that you should not use the modern SL "Energy Conserving" oils in your motorcycle......"
[edit]More good reasons why you don't want to use car oil in bikes
http://www.thumperfaq.com/oil.htm
Q: IS AUTOMOTIVE MOTOR OIL BAD FOR A MOTORCYCLE?
A: Not bad, but probably not the best. Why not? It is designed in reverse order to a motorcycle oil. The priority hierarchy of automotive motor oil is: (1) Maximize fuel economy. (2) Reduce emissions. (3) Offer protection for the moving parts. Today's automotive motor oils do not have the same degree of extreme pressure and anti-wear agents that they did just a decade ago."
Q: WILL AUTOMOTIVE MOTOR OIL HURT MY BIKE?
A: It could. If you're using an automotive motor oil in your racing four-stroke, you're not buying the best protection. An API SL oil is missing vital anti-wear components: the most common being zinc, phosphorus and sulfur. These agents are harmful to the catalyst that is used to diminish the level of pollutants in automobile exhaust.
Q: WILL AUTOMOTIVE OIL HURT MY CLUTCH?
A: Yes. The friction modifiers in motor oil improve fuel economy by making it easier for the gears, bearings, pistons and rings to slip, slide and turn inside the engine. Unfortunately, these friction-minimizing agents also make it easier for the clutch in a motorcycle to slip. If you are using automotive motor oil in your bike, apart from CRFs, you are losing hook-up and acceleration, as well as reducing the life of the clutch.
Q: WHY SHOULD I MEMORIZE THE ACRONYM "JASO"?
A: As soon as it became apparent that the American government was mandating economy over protection, the Japanese Automotive Standards Organization (JASO) developed a standard specifically for performance fourstroke motorcycles. JASO designates two different four-stroke oil classifications: MA and MB. The MB oil is low friction and the MA is sans the friction enhancers.
Q: WHY ARE MOTORCYCLE SPECIFIC OILS BETTER?
A: Motorcycle specific oils are pumped up with five times the anti-wear, anti-scuff and extreme pressure additives of regular motor oil. As an added plus, motorcycle oil does not include molybdenum disulfide and other friction modifiers that wreak havoc on clutch performance.
Maxima, a popular motorcycle oil supplier, starts with an API SG Service Category base oil, the last formulation that wasn't regulated as to the amount of zinc-dialkyldithiophosphate (zinc, phosphorus and sulfur) it could contain. Maxima then boosts protection through a proprietary mix of performance additives. The end result is a motorcycle oil that doesn't break down under extreme heat and is tough enough to cushion meshing gears.
Q: WHICH FOUR-STROKE RACING OIL SHOULD I USE?
A: If the bottle of oil doesn't list that it is an API SG Service Category or JASO MA spec, it's not good enough for your motocross bike. Although a bottle of oil might say "motorcycle specific" or "safe in wet clutches," the best endorsement is the API SG or JASO MA designation. It's better to be safe than sorry.
[edit]Finally the best answer your can get
http://www.motorexuk.com/info/jaso.html
In many 4-stroke motorbikes, the motor oi lubrcates the transmission and clutch as well as the engne. If a car grade motor oil is used clutch slipping may occur at high power loads. But if you see the JASO MA specification on the oil container, you can be sure that the clutch will always bite.
Motorcycle engines place different demands on motor oils than do passenger vehicles. In the case of passenger vehicles, the focus is on fuel economy and extended oil hange intervals, factors that by the nature of things are not important with motorcycles. On bikess, engines offering increasingly higher torques and RPMs are being used to genertae more and more power. And this is where oil additives are causing the wet clutches used on bikes to slip.
JASO MA Offers an answer
In response to the requests from leading motorcycle manufacturers, the japanese Automobile Standards Organisation (JASO) has introduced JASO MA and MB, the first specifications to apply solely to motor oils for 4-stroke motorcycle with wet clutches. These standards set additional lubricant requirements beyond the spark-ignition motor oil grades defined by API or ACEA.
The JASO T 903 bench test determines coefficients of friction under various operating conditions compared with the reference oil. The results allow oils to be divided into two catagories:
MA = Non Slipping Oil
MB = Slipping Oil
Coefficient of friction measurements that conform to MA requirements guaruntee that clutch slipping will not occur under any load condition on even the most high performance racing bikes. These values are therefore specified by leading motorcycle manufacturers...."
from http://www2.petrobras.com.br/p...o.....;/perguntas.htm
The additive levels recommended for four-cycle motorcycles are generally characteristic of oils with API SF or SG performance. API SH, SJ and SL oils have an additive level that could be detrimental to the running of the motorcycle gear system, which is also lubricated by the engine oil.
[edit]Can I use car engine oil in my motorbike then ?
http://www.carbibles.com/engineoil_bible.html
Q. Can I use car engine oil in my motorbike then?
A. No you can't.
Well, actually you can in some cases. The real answer to this question lies in the type of motorbike you own. If you own a Bike with a wet clutch (ie. where the clutch sits partially submerged in the sump oil) and you dump car oil into it, all sorts of nasty things happen. Oils formulated for car engines have friction-modifiers in them. When the engine oil gets into the clutch, the friction-modifiers get to work and you'll end up with a clutch that won't bite. Bike oils generally don't have friction-modifiers, so they don't have this problem. If you're not sure, check for a JASO MA spec on the bottle. If you see that on the label, then it means the oil has been tested and confirmed to work with a wet clutch. ......"
[edit]Summary
API rating is usually for car oils . The ratings are given once in about 3 years or so . Each new rating refers to improvement over the previous version . Ex - SL is better than SG and SM better than SL and SG etc but what you have to note is that these are ratings for engine oils to be used in passenger cars . (the API website refers to passenger car engines as automotive engines - just look at the spec chart . Ratings for motobike engine oils not given by API . JASO is the body which gives ratings for motobile engine oils.)
No matter what the API rating is , Unless a given grade of oil is rated as JASO MA , or unless the manufacturer claims that it is JASO MA certified , do no use it in your Bike since JASO MA is the only standard rating in the world to be referred to when you use engine oils in your 4stroke motobike engines which have a wet clutch multiplate setup.
Do not use JASO MB - it is for low friction engines and it is not for use in our bikes . Check the manual of your motobike - the recommended engine oil is always JASO MA and not MB.
Thus , passenger car oils are not suitable for motorbikes in most cases . There are very rare cases where you a API rated oil which might be rated as SL but still meets JASO MA ratings.
*******************************************
Are you missing some thing here or I'm I thinking wrong. But the clutches that they are talking about are not the clutches that the drive belt runs on but the clutch and or clutch plates inside the engine. The oil will have no affect on the drive and driven clutch since there is no oil out side the engine.
*********************************************
I don't run synthetic oil and will not because of the dirt that gets into the oil through the air filter and fuel mixture and into the cylinder. The most I want to run the oil in the engine is 500 miles. Synthetic is to allow you to run the oil longer between changes. (1000 to 2000 and more) I don't want this oil with the dust that got into it in the engine any longer than needed. We all run these ATV in a dust and dirt environment and it comes in through the carb. Years ago I ran a womens nylon stocking on the under (after side) of the air filter and I was amazed at the dust, dirt that got to the nylon through the air filter. The dirt does not leave the oil and I will not run the added dirt for longer than needed.
Synthetic oil is fine in a clean environment and the perfict world but we don't run our ATV's in that kind of world off road. That is my option and my engine and no synthetic for me. Next time you drain the oil what do you find in the oil and how long do you want the added dirt working on your engine. Oil if cheap compared to a $2000 engine rebuild.
thought this was interesting. i know alot of you already know this but i figured for anyone wondering why they cant use regular oil in there atvs. ill put the link because theres more info on the page but ill post the artcle as well.
http://www.bikenomads.com/wiki...p/D...ar_oil_in_bikes
Car oils in Bikes ?
A lot of people have used engine oils meant for cars in their bikes and claim that there is absolutely nothing wrong in doing so since they cannot find any damage .
The damage is certainly not perceptible to you , but such engine oils undoubtedly damage the internals . A brief intro for those who don't want to read the lengthy post-
Most car oils are rated as API SF, SG, SL and the latest being SM (not yet avail in India)
These ratings are given once in three years and each new rating is an improvement over the previous one . The ratings are in the same order as the english aphabets . The newer is better . so SM is better than SL and SL is better than SG etc.
Car engine oils have friction modifiers in them . Motorbike engine oils - specifically four stroke engines with a wet clutch multiplate setup do not require oils with friction modifiers . Modifiers can increase or decrease the friction , but most of the modifiers used are to reduce friction.
In my earlier post wrt to synth oils I have already explained why synthetic oils sometimes cause the clutch to slip .
[edit]Recap - Synthetic Oils
Recap - synth oils meant for cars when used in bike will cause clutch to slip because car synth oils have friction reducers which are not requried in wet clutch motorbikes. The oil in wet clutch motorbikes need the oil only as a coolant not a lubricant . The lubing is required for the engine and not the clutch in this case. Hence use only specially formulated motorbike syth oils and not mobil 1 etc in bikes. Synth oils are available for mobikes specifically - ex motul 300V.
[edit]Bike spec oils
coming back - The SL and SM ratings have friction reduction modifiers which are required in cars but for the same reason as explained above, they are not suitable for wet clutch multiplates . Apart from the clutch it is reported to cause damage to engine as well . The links for all of this is given below.
The only API ratings that are applicable to most indian motobike engines are oils that are of API SF or SG ratings . Check any bike manual and most of them are of this specification .
The only body which is rates oils for use in 4stroke wet clutch bikes is JASO - Japanese Automotives Standards Organisation (http://www.jsae.or.jp/e07pub/jaso_e.html) . There are two ratings from JASO - MA and MB . MA for hi friction engines and MB for low friction engines . MB is never recommened for any indian bike . As explained previously its for low friction application - not for our kind of bikes.
Always use JASO MA grade oil . It doesnt matter what the API rating is , if its JASO MA - you are guaranteed that the clutch won't slip and as long as the oil is not API SL and above you are guaranteed that the oil is not harming the engine. All the relevant links are given below.
[edit]Resarch from the Net
From http://www.sportrider.com/tech/146_0308_oil/
Rather than continue to rely on specifications dedicated to automobiles, the Japanese Automotive Standards Organization (or JASO) developed its own set of tests specifically for motorcycles. JASO now publishes these standards, and any oil company can label its products under this designation after passing the proper tests. JASO offers two levels of certification, MA (high friction applications) and MB (low friction applications). JASO requires that the entire product label be approved before it can carry its label. If a label does not have a box with a registration number above the MA or MB lettering, it could be nonapproved oil whose manufacturer claims its products meet JASO standards when it may not have actually passed the tests.
These standards also include a test specifically designed to measure the oil's effect on clutch lock-up, as well as heat stability and several other factors related to motorcycle engines. Our advice here is pretty simple: Read your manual, and if it calls for an API SG oil, use that. Don't substitute a higher API designation oil like SL, because it will contain less of some additives like phosphorus, and it may contain other additives that will yield higher fuel economy in a car but could cause slippage in your clutch. (More on that later.)
[edit]Why should you not use car engine oil in bikes
http://www.math.uwaterloo.ca/~...nder/oil_opinion.html
None of the arguments I've provided so far have relied on the familiar old ideas about motorcycle engines being harder on oil than car engines that are so contentious in the debate. What I've presented so far is sufficient to show why you should not use modern typical car oil in typical motorcycles. But let's at least mention some of the old reasons.
Zinc from ZDDP. Zinc is an anti-wear additive typically found in motorcycle-specific oils at higher levels than in car oils. The chemical that provides it is ZDDP, zinc dialkyl dithiophosphate.
Phosphorus from ZDDP. This ingredient is helpful for preventing gear wear. It is used in motorcycle engine oils to help protect the transmission. But phosphorus is bad for catalytic converters, so car oils, which are not used to lubricate transmission gears, have very little phosphorus.
Viscosity. The common car oils are 10W30 or lighter, like 5W30 and 0W30. These are too thin for motorcycles. Most motorcycles call for 10W40 or heavier in order to support bearings, resist against consumption due to volatility, and so on.
The debate over factors such as these often revolves around questions of the degree to which your engine actually experiences the extreme conditions that specialized formulations are intended to protect against, the degree to which simple use of ordinary oil with a much higher frequency of replacement would offer similar protection, and the relatively high cost of motorcycle-specific oils.
Anectodal stories abound, but as single data points, they're not worth much. When the motorcycle manufacturers themselves, who have no vested interest in whose oil you buy, warn against the use of car oil for specific reasons, and when the oil industry itself acknowledges this difference in requirements by responding with a new set of standards for motorcycle-specific oils, I think it is pretty safe to put your trust in the recommendation that you should not use the modern SL "Energy Conserving" oils in your motorcycle......"
[edit]More good reasons why you don't want to use car oil in bikes
http://www.thumperfaq.com/oil.htm
Q: IS AUTOMOTIVE MOTOR OIL BAD FOR A MOTORCYCLE?
A: Not bad, but probably not the best. Why not? It is designed in reverse order to a motorcycle oil. The priority hierarchy of automotive motor oil is: (1) Maximize fuel economy. (2) Reduce emissions. (3) Offer protection for the moving parts. Today's automotive motor oils do not have the same degree of extreme pressure and anti-wear agents that they did just a decade ago."
Q: WILL AUTOMOTIVE MOTOR OIL HURT MY BIKE?
A: It could. If you're using an automotive motor oil in your racing four-stroke, you're not buying the best protection. An API SL oil is missing vital anti-wear components: the most common being zinc, phosphorus and sulfur. These agents are harmful to the catalyst that is used to diminish the level of pollutants in automobile exhaust.
Q: WILL AUTOMOTIVE OIL HURT MY CLUTCH?
A: Yes. The friction modifiers in motor oil improve fuel economy by making it easier for the gears, bearings, pistons and rings to slip, slide and turn inside the engine. Unfortunately, these friction-minimizing agents also make it easier for the clutch in a motorcycle to slip. If you are using automotive motor oil in your bike, apart from CRFs, you are losing hook-up and acceleration, as well as reducing the life of the clutch.
Q: WHY SHOULD I MEMORIZE THE ACRONYM "JASO"?
A: As soon as it became apparent that the American government was mandating economy over protection, the Japanese Automotive Standards Organization (JASO) developed a standard specifically for performance fourstroke motorcycles. JASO designates two different four-stroke oil classifications: MA and MB. The MB oil is low friction and the MA is sans the friction enhancers.
Q: WHY ARE MOTORCYCLE SPECIFIC OILS BETTER?
A: Motorcycle specific oils are pumped up with five times the anti-wear, anti-scuff and extreme pressure additives of regular motor oil. As an added plus, motorcycle oil does not include molybdenum disulfide and other friction modifiers that wreak havoc on clutch performance.
Maxima, a popular motorcycle oil supplier, starts with an API SG Service Category base oil, the last formulation that wasn't regulated as to the amount of zinc-dialkyldithiophosphate (zinc, phosphorus and sulfur) it could contain. Maxima then boosts protection through a proprietary mix of performance additives. The end result is a motorcycle oil that doesn't break down under extreme heat and is tough enough to cushion meshing gears.
Q: WHICH FOUR-STROKE RACING OIL SHOULD I USE?
A: If the bottle of oil doesn't list that it is an API SG Service Category or JASO MA spec, it's not good enough for your motocross bike. Although a bottle of oil might say "motorcycle specific" or "safe in wet clutches," the best endorsement is the API SG or JASO MA designation. It's better to be safe than sorry.
[edit]Finally the best answer your can get
http://www.motorexuk.com/info/jaso.html
In many 4-stroke motorbikes, the motor oi lubrcates the transmission and clutch as well as the engne. If a car grade motor oil is used clutch slipping may occur at high power loads. But if you see the JASO MA specification on the oil container, you can be sure that the clutch will always bite.
Motorcycle engines place different demands on motor oils than do passenger vehicles. In the case of passenger vehicles, the focus is on fuel economy and extended oil hange intervals, factors that by the nature of things are not important with motorcycles. On bikess, engines offering increasingly higher torques and RPMs are being used to genertae more and more power. And this is where oil additives are causing the wet clutches used on bikes to slip.
JASO MA Offers an answer
In response to the requests from leading motorcycle manufacturers, the japanese Automobile Standards Organisation (JASO) has introduced JASO MA and MB, the first specifications to apply solely to motor oils for 4-stroke motorcycle with wet clutches. These standards set additional lubricant requirements beyond the spark-ignition motor oil grades defined by API or ACEA.
The JASO T 903 bench test determines coefficients of friction under various operating conditions compared with the reference oil. The results allow oils to be divided into two catagories:
MA = Non Slipping Oil
MB = Slipping Oil
Coefficient of friction measurements that conform to MA requirements guaruntee that clutch slipping will not occur under any load condition on even the most high performance racing bikes. These values are therefore specified by leading motorcycle manufacturers...."
from http://www2.petrobras.com.br/p...o.....;/perguntas.htm
The additive levels recommended for four-cycle motorcycles are generally characteristic of oils with API SF or SG performance. API SH, SJ and SL oils have an additive level that could be detrimental to the running of the motorcycle gear system, which is also lubricated by the engine oil.
[edit]Can I use car engine oil in my motorbike then ?
http://www.carbibles.com/engineoil_bible.html
Q. Can I use car engine oil in my motorbike then?
A. No you can't.
Well, actually you can in some cases. The real answer to this question lies in the type of motorbike you own. If you own a Bike with a wet clutch (ie. where the clutch sits partially submerged in the sump oil) and you dump car oil into it, all sorts of nasty things happen. Oils formulated for car engines have friction-modifiers in them. When the engine oil gets into the clutch, the friction-modifiers get to work and you'll end up with a clutch that won't bite. Bike oils generally don't have friction-modifiers, so they don't have this problem. If you're not sure, check for a JASO MA spec on the bottle. If you see that on the label, then it means the oil has been tested and confirmed to work with a wet clutch. ......"
[edit]Summary
API rating is usually for car oils . The ratings are given once in about 3 years or so . Each new rating refers to improvement over the previous version . Ex - SL is better than SG and SM better than SL and SG etc but what you have to note is that these are ratings for engine oils to be used in passenger cars . (the API website refers to passenger car engines as automotive engines - just look at the spec chart . Ratings for motobike engine oils not given by API . JASO is the body which gives ratings for motobile engine oils.)
No matter what the API rating is , Unless a given grade of oil is rated as JASO MA , or unless the manufacturer claims that it is JASO MA certified , do no use it in your Bike since JASO MA is the only standard rating in the world to be referred to when you use engine oils in your 4stroke motobike engines which have a wet clutch multiplate setup.
Do not use JASO MB - it is for low friction engines and it is not for use in our bikes . Check the manual of your motobike - the recommended engine oil is always JASO MA and not MB.
Thus , passenger car oils are not suitable for motorbikes in most cases . There are very rare cases where you a API rated oil which might be rated as SL but still meets JASO MA ratings.
*******************************************
Are you missing some thing here or I'm I thinking wrong. But the clutches that they are talking about are not the clutches that the drive belt runs on but the clutch and or clutch plates inside the engine. The oil will have no affect on the drive and driven clutch since there is no oil out side the engine.
*********************************************
I don't run synthetic oil and will not because of the dirt that gets into the oil through the air filter and fuel mixture and into the cylinder. The most I want to run the oil in the engine is 500 miles. Synthetic is to allow you to run the oil longer between changes. (1000 to 2000 and more) I don't want this oil with the dust that got into it in the engine any longer than needed. We all run these ATV in a dust and dirt environment and it comes in through the carb. Years ago I ran a womens nylon stocking on the under (after side) of the air filter and I was amazed at the dust, dirt that got to the nylon through the air filter. The dirt does not leave the oil and I will not run the added dirt for longer than needed.
Synthetic oil is fine in a clean environment and the perfict world but we don't run our ATV's in that kind of world off road. That is my option and my engine and no synthetic for me. Next time you drain the oil what do you find in the oil and how long do you want the added dirt working on your engine. Oil if cheap compared to a $2000 engine rebuild.
