All 2st Increasing oil = increased compression?

I'll have to check but I don't recall the information sheets for Amsoil Interceptor or Dominator referring to engine manufacturer's recommendations for ratio; instead they recommend 50:1...

Interceptor Info

Dominator Info

Someone else please read through 'em and make sure I'm not crazy...

Who do you think knows more about your engine, the guy who makes it or the the guy that sells you oil?

So they do. Huh, imagine that. I've never used Amsoil. For the Sabre Pro they even recommend 100:1!

Ya' learn something new every day.

I could actually believe them since they say to run at 50:1 - not that crazy.

basic 2 stroke theory, lean refers to the amout of fuel, 50:1 (2%) is more rich in fuel than 32:1. but has lower percentage of oil in the fuel.

more fuel for the fire, everyone (all over the mighty internet) is always chasing jetting and it appears everyone seems use different mix ratios as well as different oil brands (with different specs) as well as different fuels ( again with different specs) at different press/altitudes/temps.
Scientifically most of these oil/fuel jetting threads are invalid because of no control on data or the methods.
use what the oem used to spec the machine from the data book/manual this will get you far closer to optimum settings (usually a bit on the safe rich side) then chasing different ratios etc etc. most oem specs are set with pro testers that keep in mind regualar folks balance to max power with longetivity.
again this is also an opinion.... but i believe the oem engineers will tell you the same. Use an oil with the same spec that oem used at the same ratio with recommended fuel. You should be very close to good with that setting. my tuppence

I've run it (Interceptor) at 50:1 but trailside math is a pain, and I don't want to look silly getting my cell phone out to use as a calculator. So now I mix my fuel at 42.66666666666666666667 : 1 since that works out to 3oz per gallon (easy math) and the stabil bottle that I carry my premix in measures in 1/4 oz increments...

i've used amsoil on super-ugly marthon 1st-2nd gear rides at 100:1, with a few sand washes between elements, no issues at all. i wouldnt recomend it at that ratio for wider-open riding or racing though.

i've used almost every oil at every conceaveable ratio. what matters most is using it as prescribed by the oil maker and the intended use. the opperator has to strike a balance. WFO racing, causal trail riding, and uber-ugly marathon death marches are not the same.

oil wont raise your compression. it may increase your cylinder seal slightly temporarily while doing a "compression test". but that reading is defeted by actual running and the pre-combustion pressures in a worn engine (blow-by).

also- oil is not compressable. something will have to give be it a land, crown, rod etc if one tried to significantly raise a compression reading in a perfectly, or even not so perfectly, sealed cylinder. that's a fact of physics, a law. try and break it and something else will first. hydro-static lock = bad news for internals. and yer wallet.

a compression "ratio" is determined by the engine's components and stroke.

a compression reading or "test" is simply how much pressure that cyinder generates on the compression stroke, wet or dry.

how much pressure is generated depends on components, tollerance, clearance and wear. not how much oil there is.

oil is for lubricating the crank mostly, the piston also gets a little and the rings scrape the wall clean and "seal" to an extent, "wet" or dry, and, to their limit based on many mechanical factors. more oil dont = more compression. it will, however, = extreme fouling and reduced sealing.

there is a huge difference and a 2-cycle engine will produce more power slightly rich, than even a tiny bit lean, over a broader range of opperating tempratures.

pistons heat up under load. hotter piston = more fuel. more fuel = more power.

But the point is who knows more about the oil that you are putting in your engine ??? Not all oils are equal. Nor designed the same.

I would bet they are closer than you think.

back on topic- if anyone is really concnerned with compression- pull your pipe, look at the piston, if it is fouled from blowby or has shiny windows on the skirt, yank the jug, measure it first, then the piston, then the ring gap, replace as nec. after assbly it WILL feel like it has a lot more compression before starting it, but after running in it wont.

back off topic- guys (and gals!!!).... look, i'll make it easy for ya. pick an oil, ANY modern oil be it Motul, Maixma, Spectro, HP2, Yamalube, Spoog-a-roo-nomore, who cares!!! PICK ONE. then, run it at 40 or 50:1, jet your bike to that and get on with life. unless you are compensating for some extreme, and i mean EXTREME conditions or road-race- which you are not, then 40 or 50:1 will sastify ALL your requirements. i've never, NEVER sezied a bike running 40 or 50:1 when jetted propperly, reagrdless of oil. even 30w Penzoil in an emergency. i've even made it back to camp babying the thing on 2 gallons of straight gas mixed with one quart left of 50:1 Spectro i had in my tank. whats that, like 3000:1? rode like that for over a half-hour. didnt hurt a damn thing as i took it easy.

pick an oil- mix it 40-50:1, jet your bike to that and be done with it.

life's too short people!!!

The oil bases all come from the same 4 or 5 sources. There are only a few folks still capable of refining crude and creating synthetics in today’s monster-conglomerate dominated economy. The only real difference in the boutique oils (Bel-ray, Motorex, Motul, Spectro, Red-line, Amsoil...) are the additives. Even then, they all use the same additives, just in different ratios.

It really is up to you what you run. Your choice and no one can take that away from you. In my case (all just personal experience and opinion here), I used to run 32:1 years and years ago. I switched to 50:1 about 25 years back until about 3 or 4 years ago. In retrospect, I did it to prevent deposits on the head and piston crown, which may have been valid concern back then. The last few years I’ve been using 40:1 because I did not like the ‘scuffing’ on the piston skirt I got on my son’s race bikes with the 50:1. Funny thing is, still no build-up on the crown or head. Since then, however, the bikes start better. Especially in those dead engine starts for hare scrambles. They also have notably less piston scuffing. Just recently (a few weeks ago) I got 2 new bikes and have been running them at 32:1. I’m going to continue to run them at 32:1 and monitor. I think the engineers at Husky are on to something.

ok you bunch of thread jackin' einstien's....

what it really all boils down to for me is, since you could almost throw a blanket over 99% of 2-stroke oils for the most part....

i choose my oil based on smell...the closer it smells to bean oil, the more apt i am to use it.

Wooot!

:jawdrop: :bonk:

now this is starting to get scientific!

my brand of oil's best cuz....

my muffler smells better 'n alla yers....

'cept maybe dirtdame's.