Extra Spooge - theory

[Goat]

A couple months later and it looks like this, so I dropped 1 MJ size (148) I don’t think I’m close to lean yet.

[Goat]

Can we live with this much spooge? This is first hard test with the 148MJ.
7 Motos at the MX track. Will have a look at the plug, one I buy another box of extras

[KDXGarage]

Does look better!

[MoonStomper]

Please fill this 'hole in my knowledge'... you guys speak of needles like 'DEK' and others, what is the OEM needle, and what are the differences? Or if you know where I can go for a good resource to get up to speed, please direct me there. Thanks!!!

[KDXGarage]

Happy reading :-)

I predict you would like a C taper.

viewforum.php?f=105

[MoonStomper]

Thanks - started reading through all this - it's going to take some studying to wrap my brain around it. BTW - I asked Jeff Fredette yesterday about changing out the slide. He said they "never changed theirs because slides were like a hundred bucks."

[KDXGarage]

That guy could ride a Walmart bike in the Tour de France.

[Goofaroo]

Have you tried the 87 octane ethanol free fuel and mixing at 50:1? I’m guessing you’re bike will run more crisp, less spooge, and less pollution.

[Goat]

I have run 87 real gas at 32:1. Never tried 40 or 50. I have always liked 32 in my saws and bikes to get that little better ring seal.
So far I can’t tell dif between the 87 and 92 E10. So was thinking to go back to real gas anyway. Just to help make sure nothing gets gummy. I run real gas in all my other machines, but they do not get pushed as hard as the KDX.
But I suppose it wouldn’t hurt to experiment a little.

Has anyone ever found predetonation from running 87?
I have never heard any knocking.... but at 8:1 may not be very likely to happen.

[KDXGarage]

Yes, 87 is not good enough for me.

[Goofaroo]

You will get a slight power increase simply because the 87 octane is more volatile than 92 but the real advantage is that it will burn cleaner. You’ll get less carbon buildup in your combustion chamber and less pollution spewed into the environment. Not to mention the benefits of straight gas vs ethanol. Synthetic oil at 50:1 will also create a cleaner burn. I have run that combo for a few decades in my saws, trimmers, and bikes with perfect results.

I do motorcycle and small engine repair in my backyard shop and routinely see what too much oil and high octane fuel will do to combustion chambers and spark arrestors.
Save yourself some money and do your bike a favor and run the appropriate fuel and the right amount of oil.

[MoonStomper]

You will get a slight power increase simply because the 87 octane is more volatile than 92 but the real advantage is that it will burn cleaner. You’ll get less carbon buildup in your combustion chamber and less pollution spewed into the environment. Not to mention the benefits of straight gas vs ethanol. Synthetic oil at 50:1 will also create a cleaner burn. I have run that combo for a few decades in my saws, trimmers, and bikes with perfect results.

I do motorcycle and small engine repair in my backyard shop and routinely see what too much oil and high octane fuel will do to combustion chambers and spark arrestors.
Save yourself some money and do your bike a favor and run the appropriate fuel and the right amount of oil.

Goofaroo... based on your experience: in order to simplify my life, is there any harm in running my Husqvarna 346XP chainsaw (manual calls for 50:1), my son’s KTM 144 SX (40:1), and my KDX (32:1) all on the same gas; 90 octane non-E @ 50:1? How would you expect it to affect their performance if it doesn’t harm the engines? I’ve been running the bikes on non-E 90 @ 40:1 and the saw on non-E 87 @ 50:1. Thanks!

[Goofaroo]

You will get a slight power increase simply because the 87 octane is more volatile than 92 but the real advantage is that it will burn cleaner. You’ll get less carbon buildup in your combustion chamber and less pollution spewed into the environment. Not to mention the benefits of straight gas vs ethanol. Synthetic oil at 50:1 will also create a cleaner burn. I have run that combo for a few decades in my saws, trimmers, and bikes with perfect results.

I do motorcycle and small engine repair in my backyard shop and routinely see what too much oil and high octane fuel will do to combustion chambers and spark arrestors.
Save yourself some money and do your bike a favor and run the appropriate fuel and the right amount of oil.

Goofaroo... based on your experience: in order to simplify my life, is there any harm in running my Husqvarna 346XP chainsaw (manual calls for 50:1), my son’s KTM 144 SX (40:1), and my KDX (32:1) all on the same gas; 90 octane non-E @ 50:1? How would you expect it to affect their performance if it doesn’t harm the engines? I’ve been running the bikes on non-E 90 @ 40:1 and the saw on non-E 87 @ 50:1. Thanks!

Run it all on 87 at 50:1. You will have a very insignificant increase in power but a much cleaner burn in all of your engines. Do you understand what octane is? Higher octane fuels simply have more octane added to them. It is an anti-knock agent that simply makes the fuel less “volatile” or “explosive” to prevent detonation and preignition. Unless you have a high strung high compression motor running a lot of ignition advance your motor won’t burn it as thoroughly as it will burn a more “explosive” fuel. Thus a dirtier running engine.

I just mix up 5 gallons at a time of whatever synthetic 2 stroke oil I can get the best deal on at the bike shop, mix it with 87 non ethanol, and run it in all of my personal bikes and equipment as well as my customer’s equipment.

[Goat]

Higher octane does not make gas less explosive. It raises ignition temp. Very much needed for higher compressions so that it ignites from engine spark and not engine heat.
I would never run 87 in an engine with higher compression or even average compression with heavily advanced timing.
I just do not know if an 8:1 kdx w/ stock timing needs the higher octane. My hipo cars will never see 87 gas.
The normal train of thought is to run non-ethanol gas if you can. But never at the risk of predetonation.
And food for the other thought:
More 2T oil generally increases ring seal and as rule of thumb produces more power than less oil mix. If you don’t mind the smoke.
More oil typically produces more power since higher compression is more of a power producer than the better efficiency of real vs E10 gas. But you will see a loss in mpg. The given is that it takes more E10 gas to do the same work as real gas, not necessarily that E10 can’t perform the same work.
But I do fully agree there is a limit to how much smoke you want to put up with. Along with too many mc’s, I have 4 chainsaws for different jobs. My saw shop recommends 32:1 vs 40 or 50 for power & longevity of the motor.
Don’t mean to start flame. But don’t think a 50:1 mix produces more power than a 32 or even 26 mix.

[MoonStomper]

Thanks. Yeah I’m up to speed on what octane does, but trying to find the best balance for my bikes and saws in one can. I’m limited on local access only to non-E 90 and lower. The KTM needs the higher octane because of the high compression head on that bike. I’ll probably stick with the 40:1 since it won’t hurt it or my saw. Saw starts easier with the 87 though, if I use half choke it fires right up on 90.

[Goofaroo]

Higher octane does not make gas less explosive. It raises ignition temp. Very much needed for higher compressions so that it ignites from engine spark and not engine heat.
I would never run 87 in an engine with higher compression or even average compression with heavily advanced timing.
I just do not know if an 8:1 kdx w/ stock timing needs the higher octane. My hipo cars will never see 87 gas.
The normal train of thought is to run non-ethanol gas if you can. But never at the risk of predetonation.
And food for the other thought:
More 2T oil generally increases ring seal and as rule of thumb produces more power than less oil mix. If you don’t mind the smoke.
More oil typically produces more power since higher compression is more of a power producer than the better efficiency of real vs E10 gas. But you will see a loss in mpg. The given is that it takes more E10 gas to do the same work as real gas, not necessarily that E10 can’t perform the same work.
But I do fully agree there is a limit to how much smoke you want to put up with. Along with too many mc’s, I have 4 chainsaws for different jobs. My saw shop recommends 32:1 vs 40 or 50 for power & longevity of the motor.
Don’t mean to start flame. But don’t think a 50:1 mix produces more power than a 32 or even 26 mix.

[Goofaroo]

Nope. Octane is simply an additive that makes the fuel less volatile. The lower the octane the more explosive the fuel becomes. Unless you have an engine that requires higher octane to prevent preignition the fuel simply won’t burn as thoroughly and will dirty up the combustion chamber. If you try 87 and it pings then try 89. If that pings then try higher octane. You always want to use the lowest octane you can. On two strokes in stock configuration if you get preignition it could be caused by other factors such as air leaks or lean jetting.

Anyway this is just my $.02. Run whatever makes you comfortable. All of your bikes and equipment will definitely run on 92 octane and 32:1. Just not quite as efficiently and cleanly.

[Goat]

Can you hear ping (predetonation) on loud ass 2T (like mc or saw)? I suppose you’d feel it as much as hear it.
I haven’t run into it that I know of, so agree I should do some more experimenting, since I don’t think any of my 2T stuff is high compression. And I fully agree lowest octane real gas you can run is best.
I got 2 of my saws from my brother-in-law who has cut more wood than me, and he’s in the 50:1 camp. So probably should try it and see if I like it, instead of just sticking with my old ways.

[firsthere]

The saw and weed eater get the same fuel mix as the KDX. Been that way for 30 years. The KDX is the only one that drips spooge though, probably because its not run at such high RPM's.

[Goofaroo]

If Echo, Stihl, and Husky (among others) wanted you to run 32:1 or 40:1 why would all of their small 2 Stroke oil bottles be 2.6 ounces? It’s intended as a convenience so you can just dump it into a 1 gallon gas can and have 50:1.