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30:1 or 32:1

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My 02 250 says to run 30:1. I have always ran 32:1. I am getting a stream of oil of the silencer after every ride. I guess I should just run 30:1. Does this bike run rich with stock jets? Anyone know? How much oil are you guys seeing out of your silencer? I know it is pretty typical with two strokes. (my last 3 did it)

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Do you foul out many plugs at 32:1? Running at 30:1 should make for even more oil coming out. I run mine at 40:1 (06 RM250) with stock jetting and pump gas. The manual always has the ratio too rich.

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Do you foul out many plugs at 32:1? Running at 30:1 should make for even more oil coming out. I run mine at 40:1 (06 RM250) with stock jetting and pump gas. The manual always has the ratio too rich.

wrong , the oil is not what fouls out plugs... 40:1 is actually richer then 30:1 .. The reason your getting more fuel at 40:1 then 30:1 and the fuel is what makes the bike lean or rich not oil. For a 250 run 32:1 and jet. As far as spooge they call it oil coming out silencer, your rich try leaning out a bit.

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wrong , the oil is not what fouls out plugs... 40:1 is actually richer then 30:1 .. The reason your getting more fuel at 40:1 then 30:1 and the fuel is what makes the bike lean or rich not oil. For a 250 run 32:1 and jet.

Exactly. How many times do we have to cover this?

To the original poster:

What bike are we talking about?

You can stick with 32:1, but next time you have the top end apart make sure to test the amount of premix you have in your crankase.

Your problem likely lies in an out of spec. float or too rich jets. Bikes are usually rich from the factory.

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Exactly. How many times do we have to cover this?

To the original poster:

What bike are we talking about?

You can stick with 32:1, but next time you have the top end apart make sure to test the amount of premix you have in your crankase.

Your problem likely lies in an out of spec. float or too rich jets. Bikes are usually rich from the factory.

I have no clue I have posted it more then a few times myself lol ..

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wrong , the oil is not what fouls out plugs... 40:1 is actually richer then 30:1 .. The reason your getting more fuel at 40:1 then 30:1 and the fuel is what makes the bike lean or rich not oil. For a 250 run 32:1 and jet. As far as spooge they call it oil coming out silencer, your rich try leaning out a bit.

I'm not talking about air/fuel mixture. I'm talking about fuel/oil mixture. If you richen the pre-mix ratio (20:1 as opposed to 30:1) there is more oil and less fuel in the same volume of liquid, which effectively leans the air-fuel ratio.

http://forums.everything2stroke.com/articles/6408-carb-jetting-101-part-two.html

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40:1 is not richer than 30:1. 40 parts gas to 1 part oil is much leaner than 30 parts gas to 1 part oil. If you don't think oil will foul a plug then go mix your gas 20:1 and see what happens.

Lean or rich is not about oil:gas. Its the amount of gas to air. More gas = richer. less gas = leaner.

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This was cut and pasted out of that link in my previous post. It explains it better than I can. We are all talking about the same thing...just different ways of getting there.

Fuel and Oil Mixture Ratio:

When we talk about the "fuel" in the air-fuel mixture for a two-stroke engine, we are really talking about a mixture of fuel and oil. If you richen the pre-mix ratio (20:1 as opposed to 30:1) there is more oil and less fuel in the same volume of liquid, which effectively leans the air-fuel ratio. And this fact gives the clever tuner one more tool to use when the correct jet is not available or when none of the standard jets are exactly right. You can richen the jetting by slightly reducing the pre-mix ratio (less oil). You can lean the jetting by increasing the pre-mix ratio (more oil). The best part is that changes in the pre-mix ratio affect the jetting over the entire throttle-opening range, but the changes in ratio must be small to prevent excess wear from lack of lubricating oil or fouled plugs from too much oil.

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This was cut and pasted out of that link in my previous post. It explains it better than I can. We are all talking about the same thing...just different ways of getting there.

Fuel and Oil Mixture Ratio:

When we talk about the "fuel" in the air-fuel mixture for a two-stroke engine, we are really talking about a mixture of fuel and oil. If you richen the pre-mix ratio (20:1 as opposed to 30:1) there is more oil and less fuel in the same volume of liquid, which effectively leans the air-fuel ratio. And this fact gives the clever tuner one more tool to use when the correct jet is not available or when none of the standard jets are exactly right. You can richen the jetting by slightly reducing the pre-mix ratio (less oil). You can lean the jetting by increasing the pre-mix ratio (more oil). The best part is that changes in the pre-mix ratio affect the jetting over the entire throttle-opening range, but the changes in ratio must be small to prevent excess wear from lack of lubricating oil or fouled plugs from too much oil.

Same thing I said.....

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A couple cc's of oil is not going to make much difference.

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Now this is scaring me. The guy I bought my 03 from said he used race fuel and Motol (sp?) oil and ran it at 50:1. I talked to the Suziki shop with a reliable reputation and asked him if this was correct, also telling him I was going to be running 92 gas, not race gas. He said that with the new synthetic oils, like the Motol, 50:1 was fine. I have run about 30 gals of 50:1 through it and it runs great, and hasnt blown up. Is this mix a time bomb waiting to go off? Do I need to run at 32/30:1. My last 2 stroke was a 77YZ that took 20:1, so I am concerned about the mixtures

Thanks

John in Vegas

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Who better than the oil Manufacturer to recommend the proper ratio? They designed it, they should know what ratio it will work best. Tdub

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Who better than the oil Manufacturer to recommend the proper ratio? They designed it, they should know what ratio it will work best. Tdub

well I went and reread the oil bottle again, and it didnt say anything about substituting a higher ratio, but it did only list the amounts to come up with 50:1 and 66:1.

John in Vegas

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Did you really say this??

I meant excessive spooge, i hear stories of oil dripping onto the swingarm, isnt that from too rich of an air:fuel mixture?

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Ok sorry I was out of town after I posted this. No, I have never fouled a plug. I just get a nice line of oil out of my silencer. So, going to 30:1 you would think I would see more oil comeing out. When you guys say "it's rich" well what circuit are you talking about, pilot, needle, needle height, slow jet, power jet, main, pre mix ratio or the whole thing? Should I go down one size on my main or drop my needle a notch? My bike is 06 rm 250. stock.

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jetting is all stock, fuel/air screw is 1 turn out (what manual says it should be), the only thing that is different is that I am mixing at 32:1. Less oil= richer fuel/air mixture causing more spooge. more oil= leaner fuel air mixture and less spooge. Do you think that would work? It doesn't sound like it. I guess I could just mix at 30:1 what the factory reccommends, but do you think if I mixed at 40:1, it will lessen the spooge?

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