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oil to rich?

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can running to much oil in premix cause bad performance? cuz I'm blowing plugs left and right, and i have a lot of smoke at operating temp. my float level is stock and my pj is a 25 and my main is a 350. I'm running 36 to 1 premix. but every one down here use 40 to 1. should i lean the oil out?

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oh yeah i had to gap the plug way high in order to get a little snap out of the bottom end. that seems like to much oil right? cuz with the stock gap, it justs gums up with oil. could my spark not be be getting hot enough?

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No oil pre mix ratio chanige is only a band aid fix for poor jetting. first of all to help with your getting we are going to need to know what bike and year and riding style. as for pre mix for a 250 for MX i would be at least 32:1 for tight tail some use 40:1. in my yz250 i ride and race stricly MX and use 30:1 jetted correctly i have never fouled a plug and i change mine at the 15 hour mark with the stock plug. for 125 bare min for pre mix is 32:1 for mx i was using 28:1 to 26:1 when i was a 125. a excellent engine builder well known to this site explained to me the best way to check for proper pre mix for you and your bike is on a rebuild to put a chop stick between the crank wheels to the bottom of case you want to have beween 1/8" to 1/4" of oil residue any more and your pre mix is too rich anyless and you need more oil in the mix. the topic has beaten to death and there was just a post on it this earlier this week. by the way more oil equals more power better ring seal, less friction in the cylinder and better lube for the lower end bearing

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i have a 01 125. i mainly do trail riding. and i find myself going up pretty steep hills all the time.

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I would run 32:1 in a 125. Too much oil is not your problem.

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could my ignition not be getting hot enough? because i have to gap the plug way over stock to get a little snap.

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How many hours does the top end have on it?

As far as plug fouling, if nothing has changed and you are suddenly fouling plugs left and right, it might be a crank bearing seal.

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Jetting issue, change it to suit your rideing don't change your ratio

Wornout topend

possible leaking clutchside crank seal letting in tranny fluid causeing fouling

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also i cant turn the air screw even one turn out or it bogs to bad. i know i'm not running lean because when i pull the plug out, its pretty greasy. it was only when i started to adjust the gap on the plug, the the throttle response was better. and the plug was cleaner and drier.

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also i cant turn the air screw even one turn out or it bogs to bad. i know i'm not running lean because when i pull the plug out, its pretty greasy. it was only when i started to adjust the gap on the plug, the the throttle response was better. and the plug was cleaner and drier.

That's not surprising. You're running pretty lean. Pro Circuit reccomends a 410 main with a 30 PJ. When you turn out your AS to lean it further it bogs cause it's too lean as in not enough fuel/air mixture. They also suggest running it on the second clip of the stock needle. This is all for sea level at 70*.

If you're oil fouling with this lean of jetting you might have a crank case seal that is blown and you're sucking in transmission oil. I'd keep a close eye on the quantity of oil that comes out of your transmission when you drain it. It should directly match how much you're putting in. You also say that it smokes heavily even after it warms up. If you're that lean and smoking chances are that your crankcase seal is fubar.

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WOW mdkcrf250 that is very very bad info. testing proves that a bike makes more power all the way up to 18:1 there is info on this site about it, more oil will give you better ring seal, which means more compression which means more power, also it creats less fritcion and keeps it running cooler all these things mean more power. i dont understan why over the last few years ppl are coming with this idea that less oil is better? ask any good engine builder and they will tell you this more oil is more power, and longer lasting happier engine. i would love to see these dyno of a bike making more power all the way up to the point of locking up the only reason i could see that being possible is the jetting was so far off, and jetted really lean to start with so taking the oil of the gas richened the bike up. but please dont go posting telling ppl that no oil makes more power that is so very bad info

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WOW mdkcrf250 that is very very bad info. testing proves that a bike makes more power all the way up to 18:1 there is info on this site about it, more oil will give you better ring seal, which means more compression which means more power, also it creats less fritcion and keeps it running cooler all these things mean more power. i dont understan why over the last few years ppl are coming with this idea that less oil is better? ask any good engine builder and they will tell you this more oil is more power, and longer lasting happier engine. i would love to see these dyno of a bike making more power all the way up to the point of locking up the only reason i could see that being possible is the jetting was so far off, and jetted really lean to start with so taking the oil of the gas richened the bike up. but please dont go posting telling ppl that no oil makes more power that is so very bad info

ABSOLUTELY!

mdcrf250, have you ever looked at the rings on a 4 stroke and the rings on a 2 stroke? 4 strokes get ring seal from rings, 2 strokes get ring seal from rings and oil. You cannot say that what works in one, will work in the other, since they are completely different animals from top to bottom.

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WOW mdkcrf250 that is very very bad info. testing proves that a bike makes more power all the way up to 18:1 there is info on this site about it, more oil will give you better ring seal, which means more compression which means more power, also it creats less fritcion and keeps it running cooler all these things mean more power. i dont understan why over the last few years ppl are coming with this idea that less oil is better? ask any good engine builder and they will tell you this more oil is more power, and longer lasting happier engine. i would love to see these dyno of a bike making more power all the way up to the point of locking up the only reason i could see that being possible is the jetting was so far off, and jetted really lean to start with so taking the oil of the gas richened the bike up. but please dont go posting telling ppl that no oil makes more power that is so very bad info

Can you post the info where 18:1 produces more power?

The tests I have seen were done in 1970, using air cooled engines and oil that I wouldn't use in a lawn mower. It's not 1970 anymore. Oils have come leaps and bounds.

I can tell you that most oil manufacturers today don't agree with the 18:1 garbage. Atleast the half dozen I've spoken with. And they say their testing says the opposite of what you claim.

The better the oil, the LESS you need to lubricate the same.

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Can you post the info where 18:1 produces more power?

The tests I have seen were done in 1970, using air cooled engines and oil that I wouldn't use in a lawn mower. It's not 1970 anymore. Oils have come leaps and bounds.

I can tell you that most oil manufacturers today don't agree with the 18:1 garbage. Atleast the half dozen I've spoken with. And they say their testing says the opposite of what you claim.

The better the oil, the LESS you need to lubricate the same.

Rather than digging up an old study, how bout providing one of the new ones that supports these oils of today.

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Can you post the info where 18:1 produces more power?

The tests I have seen were done in 1970, using air cooled engines and oil that I wouldn't use in a lawn mower. It's not 1970 anymore. Oils have come leaps and bounds.

I can tell you that most oil manufacturers today don't agree with the 18:1 garbage. Atleast the half dozen I've spoken with. And they say their testing says the opposite of what you claim.

The better the oil, the LESS you need to lubricate the same.

The oil manufaturers are trying to sell oil and if they say that you can run 50:1 no problem, guys see that they can use less of the oil and save money. Today's oils are great and you can get plenty of main bearing lube at 50:1 if not ridden at high RPM, especially on a big bore 2 stroke like yours. The lubrication of the oil has improved, but the mechanics of ring seal have not changed. If Yamaha thought you would get more power and the same bearing life out of 50:1 that you get out of 32:1, they would recommend it. They don't. You can believe the oil makers, I'll believe the engine makers...

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to get back on topic his problem is not pre mix ratio related i have to agree he has a crank seal leak on the transimission side or really worn rings. as for it being 1970 or 2009 like said by locomike ring seal will always be better with more oil, giving more power and longer life. 50:1 is ok for some people with certain bikes but no ok for some guys that are riding MX on tracks that are WOT. like i said above best way to see if the oil mix you are running is good for you is to check with residue between the crank wheels when apart for a rebuild you want 1/8" to 1/4" then jet according to pre mix ratio needed. what the oil bottle say or the bike oem is a guideline every rider and bike are different. as for the test i read im pretty sure it was done on a 02 RM250 not a 1970 air cooled, ill try to find it again. everyone has thier own opinion on oil amounts but no oil is not good.

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do i have to split the case in order to check the seal? and i check my tranny oil. and its at the same leve i fill it up at. 650ml

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The oil manufaturers are trying to sell oil and if they say that you can run 50:1 no problem, guys see that they can use less of the oil and save money. Today's oils are great and you can get plenty of main bearing lube at 50:1 if not ridden at high RPM, especially on a big bore 2 stroke like yours. The lubrication of the oil has improved, but the mechanics of ring seal have not changed. If Yamaha thought you would get more power and the same bearing life out of 50:1 that you get out of 32:1, they would recommend it. They don't. You can believe the oil makers, I'll believe the engine makers...

Manufacturers recommend oil ratios related to jetting.

Your assumption of oil and ring seal is incorrect. More oil does NOT insure better ring seal.

You also assume the oil manufacturers disregard longevity. Your blind assumption is also incorrect. Too many factors are involved for me to type it all out.

Call Torco, or Maxima.

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