Fuel Mixture for kx 100

Anyone know the fuel mixture ratio for a kx 100? I couldn't google it and I'm too lazy to find the owner's manual.

Thanks!

32:1 will do just fine. Rejet also.

Sven is correct, don't run less than 32:1.

I run 40:1 in my kx100

It depends on the oil!

lumpy790 wrote:

It depends on the oil!

Lumpy my friend.... I respect you quite alot as you know, but on this you and I disagree.

I don't care what kind of oil you run, using less oil than 32:1 in a small-bore is asking for trouble.

-Steve

At least we agree to disagree

But at least we mostly agree.

Why is it that different oils have different recomendations? Some say 20, 32, 40, 50 or even 100/1 Wouldnt the ones with 50 or 100/1 sell more oil if they just had you dump more in when it is not needed?

Its not how much you put in its how long it sticks to the metal surface. Every manufacturer has done 1000's of hours testing to see how well their oils perform at different ratios. They compare wear and horsepower Sure you can put more than you need but why?

I pulled this from Spectro's web site.....

Golden Spectro Pre-Mix is recommended for use in all high-performance, two-cycle engines where extreme load conditions and temperatures are expected. When mixing with gasoline, add 12 oz. of oil to four to six gallons of gasoline, depending on the size of the bike and the riding conditions. Golden Spectro is compatible with conventional petroleum oil-gas mixtures, so no special steps need to be taken when switching to Golden Spectro.

Remember: Most manufacturers assume you are using an "all purpose" two-stroke oil when recommending a pre-mix ratio. With Golden Spectro, ratios of 42:1 to 64:1 are optimum, and ratios 100:1 routinely pass lubricity tests due to its superior film strength.

I see your point, but oil in the fuel on a two stroke is not mainly about lubricity. That is only part of the reason. Good lubricity can be had with 50:1 or even less.

The oil is where the ring seal comes from. More oil = more ring seal. More ring seal = more power.

Time and time again dyno tests have been done that show more oil in the fuel creates more power. Maximum power is had at usually around 18:1. Kart racers are sticklets for maximum power because of how strict their engine rule package is. If there was an advanage to running 50:1 or 100:1 they would do it in a heartbeat. Go to a kart race and check fuel mix ratios. You'll find that most are at 18:1 to 22:1. There is a reason for that. Power.

-Steve

I have heard/Read this story before but I for 1 do not buy it. That much oil would create more drag from gumming up. = less HP. Why isnt there a cloud behind RC, CR, JS & TP ? The factorys shure would do something as simple as that if it gave them more HP.

So why dont the oil manufacturers tell you to use more to get more HP and as a side bennefit they sell more? They don't and since when have the oil companies done anything but do what would make them more $$$ ???

lumpy790 wrote:

I have heard/Read this story before but I for 1 do not buy it. That much oil would create more drag from gumming up. = less HP.

Tell ya what... Next time you are in the area, give me a yell, and we'll hit a track. We'll mix up some 20:1 fuel/oil and go for a ride. Let me do the jetting and set the plug. Thicker mixes like 20:1 work better under the more agressive riders, but with good jetting can be made to work for anyone. Most people will be fine between 32:1 and 50:1 tho. Because I'm not the fastest rider, and I tend to ride a more casual pace these days, I mix at 40:1 in my 200. But I would have no problems going to 20:1 for a day to prove a point.

Why isnt there a cloud behind RC, CR, JS & TP ? The factorys shure would do something as simple as that if it gave them more HP.

Simple. They ride hard enough to burn the oil. An expert running the engine under a full load with proper carb jetting will develop combustion chamber temps that will cleanly burn the heavier oil mix.

So why dont the oil manufacturers tell you to use more to get more HP and as a side bennefit they sell more? They don't and since when have the oil companies done anything but do what would make them more $$$ ???

Ever read the series of articles Dick Lechein did for several of the Hi-Torque mags back in the late80's/early 90's? He was pushing EXACTLY that.

-Steve

moto814 wrote:

lumpy790 wrote:

I have heard/Read this story before but I for 1 do not buy it. That much oil would create more drag from gumming up. = less HP.

Tell ya what... Next time you are in the area, give me a yell, and we'll hit a track. We'll mix up some 20:1 fuel/oil and go for a ride. Let me do the jetting and set the plug. Thicker mixes like 20:1 work better under the more agressive riders, but with good jetting can be made to work for anyone. Most people will be fine between 32:1 and 50:1 tho. Because I'm not the fastest rider, and I tend to ride a more casual pace these days, I mix at 40:1 in my 200. But I would have no problems going to 20:1 for a day to prove a point.

Why isnt there a cloud behind RC, CR, JS & TP ? The factorys shure would do something as simple as that if it gave them more HP.

Simple. They ride hard enough to burn the oil. An expert running the engine under a full load with proper carb jetting will develop combustion chamber temps that will cleanly burn the heavier oil mix.

So why dont the oil manufacturers tell you to use more to get more HP and as a side bennefit they sell more? They don't and since when have the oil companies done anything but do what would make them more $$$ ???

Ever read the series of articles Dick Lechein did for several of the Hi-Torque mags back in the late80's/early 90's? He was pushing EXACTLY that.

-Steve

whats that i smell? It must be a challenge

Grizzly600 wrote:

whats that i smell? It must be a challenge

Nah more like good premix...

-Steve

thats it! smells like some sort of....*sniff*....maxima...and...*sniff*...hmmm maybe a vanilla glade plugin?

Let us know if you two ever do a "ratio shootout" i would like to know the winner.

I can tell you the results now.

We both will win, and both will run good.

Over time, the cylinder that has more oil in the mix will have it's top ends and cranks last marginally longer.

Being that Lumpy and I both know how to jet properly, we could make either mixture run correctly. The HP numbers gained from more oil will be minute (less than one HP). Lumpy will go away from it thinking that he won the debate, and I will go away from it thinking that I won the debate. And we will both be right.

Then we will go to a sports bar and fill ourselves on some great wings!

-Steve

moto814 wrote:

I can tell you the results now.

We both will win, and both will run good.

Over time, the cylinder that has more oil in the mix will have it's top ends and cranks last marginally longer.

Being that Lumpy and I both know how to jet properly, we could make either mixture run correctly. The HP numbers gained from more oil will be minute (less than one HP). Lumpy will go away from it thinking that he won the debate, and I will go away from it thinking that I won the debate. And we will both be right.

Then we will go to a sports bar and fill ourselves on some great wings!

-Steve

haha

steve- "man i so beat you"
lumpy- "no way i totaly won"
...ect

Well thats still good. I saw an article on dirtbike.com from zenith, it said the same thing, they tested all the way down to 18:1 and only lost a total of 3-4% wich i think they said was 3 hp. So what your saying sounds right on track. I wich zenith and spank's (spanky) was still here, those guys post some usefull articles.

thats the smell!...wings