50:1 Or 40:1, Hmmmm

[GMP]

Spooge, or liquid oil droplets being blown from the exhaust in the case of a straight silencer, is a good thing IMO, as it shows complete oil propagation. This was the point of the Maxima test. With modern high flash point synthetics, PV fouling is all but eliminated. Even at 36:1, I can wipe my PV parts clean with a contact cleaner and rag after 75 - 100 hours. I run Amsoil Dominator.

There have been other tests done and documented that prove as long as jetting is corrected for it, power keeps going up in proportion to the oil in the mix, to a ratio of 16:1. Reason is better ring sealing. I beleive all these lean mfg suggested ratios are driven by emmisions standards and nothing more.

Spooge is the worst thing you can use as a base for mix and jetting, as its exhaust dependent.

[bowhunter007]

Originally Posted by GMP

Spooge, or liquid oil droplets being blown from the exhaust in the case of a straight silencer, is a good thing IMO, as it shows complete oil propagation. This was the point of the Maxima test. With modern high flash point synthetics, PV fouling is all but eliminated. Even at 36:1, I can wipe my PV parts clean with a contact cleaner and rag after 75 - 100 hours. I run Amsoil Dominator.

There have been other tests done and documented that prove as long as jetting is corrected for it, power keeps going up in proportion to the oil in the mix, to a ratio of 16:1. Reason is better ring sealing. I beleive all these lean mfg suggested ratios are driven by emmisions standards and nothing more.

Spooge is the worst thing you can use as a base for mix and jetting, as its exhaust dependent.

Not gauging mix ratio based on spooge, I get...What about excessive smoke? Same idea, as long as the engine is mechanically in good condition? With all the reasearched & posted help with my jetting...My machine is coming along fine, and a lot quicker than I surmised. I would like to get the best bang/power for my dollar, without being too greedy, since my riding skill doesn't exceed the power the bike will produce.

[andoman]

I'm a 50:1ish guy.
I'm also lazy and like ease of measurement:
To whole gal. fuel quantities < 5 gal. I use 2.5 oz oil/gal. = 51.2:1
To a 5 gal. gas in my gas can I add 13 oz oil. = 49.2:1

[GMP]

Ratio-Rite, should be in every garage. No math required.

[twowheels]

Originally Posted by GMP

Ratio-Rite, should be in every garage. No math required.

That's how it's done. If you don't like the tippy base or the fact that the spout makes it hard to seal out dirt, try the Maxima graduated cylinder with screw-on cap.

[jgas]

For years I thought 50:1 gave more power than using more oil. It just felt that way on most bikes because the bikes I was riding were not properly jetted. Finally someone jetted a bike for me and showed me how, and I learned that there is not much difference in power with any ratio IF the bike is jetted for that specific ratio. I normally use 40:1 these days to kind of strike a balance. My thinking is that if I jet for 40, and then need to bum gas from a buddy who uses a different oil or ratio, or for some reason use a higher or lower ratio than normal I probably won't foul a plug or have any problems using anything from 32-50:1 when jetted between the two. 40 just seems like a good all around ratio to me. You think you'll never need to use gas from another guys can? I got to a gas stop in an Enduro and someone had used all of my gas! That's when I learned to mark my can, especially if it looked like many others on the trailer. Luckily there was a guy there who let me bum gas from his can. He was using 50:1 and didn't have any idea what brand or type of oil he was using, said his dad mixed it I heard the bike knock once or twice when riding a gear high and lugging, but had no problems.

I read a long article by a major engine tuner, I think it was Eric Gorr, who proved with extensive testing that the more oil you used, even down to 20:1, you could jet for more power and get less wear. With that said, he admitted that there was no reason to use more than 32:1 except for motors that stayed on the pipe all the time such as drag bikes or shifter kart motors. And the power increase with 20:1 over 40:1 was a very small percentage that most riders would never notice.

I read that article many years ago, probably in the late 90s, and carbs, engine parts, porting and reeds, oil, practically everything regarding this issue has improved markedly. My guess is that with everything being better now in every way you can get away with less oil?

I raced a KX 500 hard for 4 years in Enduro, H Scrambles, and many trail rides on 40:1 Kawasaki brand racing oil. I drag raced it and rode in big sand dunes, did it all on that bike. I kept doing compression checks and it was always in spec, so I didn't rebuild it or even ring it. Finally it dropped a little compression and the cause was simply the Nikasil coating on the cylinder had worn off in one spot. Piston and rings looked like they would go another 4 years, but the top end bearing was a bit loose which I replaced along with the piston/rings since it was apart. The bottom end bearings were fine. I sold it to a buddy and it lasted another 5 years on the second top end, with the cylinder coating still not replated. That's 9 years of hard riding on 2 top ends at 40:1. The Powervalve never stuck either which was a common thing on older KXs. Is this scientific? Nope. But when I do something and it works, I generally keep doing it. If it ain't broke, don't...

[jimjim]

Any problem with switching from a non-synthetic to a full synthetic pre-mix?Do I need to do a jetting change?I currently run 40-1 on the non-synthetic.

[Fred1956]

Originally Posted by jimjim

Any problem with switching from a non-synthetic to a full synthetic pre-mix?Do I need to do a jetting change?I currently run 40-1 on the non-synthetic.

40:1 is 40:1 no matter the oil The main difference between the oils is 'lubricant efficiency' Back in the 'day' of early synthetic use they recommended breaking in an engine with non-synthetic oils to allow rings to seat before going to synthetic I was never sure if it was a marketing thing for the 'non wear' capabilities of synthetic or what

[Pepperami]

I run Putoline synthetic at 40-1

[bowhunter007]

I robbed the needle out of my wrecked GG, since it's on a stand for a while. It has a 40 pilot & 180 main(same as what I'm using). The motor in my XC250 is fresh, above & below, newly rejetted. It originally was rejetted 'cause the crank seal was leaking(former owner didn't know), causing a rich mix. Since the teardown, it's been jetted to run at 40:1. It runs clean & has more power than I can use up. The needle is somewhat of a mystery, as I am unable to find any markings(just the top of it is red). Since this machine is a former local enduro race machine, it could be an LTR needle. The bike is covered in LTR pieces. Anyway...I'm still in the 40:1 camp, for now. She seems a bit cleaner in the middle(it's difficult to be 100% sure riding around the block). Tomorrow's another day of play, on the bike. So close, yet so far away...