gas:oil ratio?

[baker250r]

hey, im runnin a race 265. what do you guys prefere for mixing ratios? some tell me 20:1, some 35:1 and others 50:1. i know the MC1 stuff it says u should mix it 50:1, but isnt that a little lean?

[Teufel]

I run my 2 strokes 50:1, I prefer Klotz products either the bean oil or R50.

The castor based oils provide superior protection at 50:1 and minimizes build up

[baker250r]

but wont 50:1 cause more wear on teh motor? i knwo klotz is the best... but all the shops around here sell MC1, and i dont want to have to always order oil, when i can just run to the shop and buy a case of MC1

[bone705]

with alot of the new oils you can get by with leaner mixes. i run maxima 927 and have always ran it at 32:1 just to be safe. it seems to do the job.

[baker250r]

so i dont gotta worry about the engine goin if i run 50:1? i mixed it 1 pint to 4 and a half gallons today.... thats nto quite 50
:1 but its little richer...

[Teufel]

arguably, less oil means less protection and increased wear. however the quality premixes offer superior protection at 50:1
Running this ratio, in my opinion, offers maximum performance without sacrificing protection.

In my experience I have used the 50:1 ratios for years without regret. If you are not competing then run 40:1 , remember no matter what ratio you run always be consious of your jetting needs. Also use a ratio cup and measure your oil and gas carefully.

P.S.

The MC 1 is a top notch product.

[Eddiesanders250]

32:1

is what ive ran it at. i think 50:1 is a little lean for racing

[pharit]

32:1+Klotz oil+114 octance gas= The sweetest smell on earth

[JTRtrx250r]

I run all my 2 strokes at 32:1

40-50:1 is much richer, more fuel =cooler motor

and remember, most oils come in diffrent viscosity or weight so 1 might call for 32:1 for a pint to 4 to 5 gallons, while the other calls for 50:1 per 5 gallons

I run HP2, the whole bottle to 4 gallons is 32:1

MC1 at 50:1 is a much fatter(richer) ratio than 32:1

pharit...NO DOUBT ABOUT IT!! haha

[baker250r]

yea, there is nothing better than the smell of 2 stroke exhaust..... but i doubt i can afford 114 ocane.... lol.... but i will be usin 111....

[papatrx]

This debate of mix ratio has been going on for years and as oil quality has increased I also have gone to a leaner synthetic mixture of 50:1 for the performance gains from jetting. I have never had any wear problems from this.

Recently though I have changed my thinking after reading some information written from some guys that are way deep into two strokes, on the level with Gorr, Jennings and Blair. It seems that after some extensive testing with different mixtures all the way down to 8:1, where extensive sputting begins, power is increased due to the loss of friction with more oil. As much as 13% more on the dyno, these are from engines that are extreme race engines and they are not worried about build up in the engine since they are torn down very frequently. Most of the cart guys that run high revs for extended periods of time are around the 20:1 mark.

I will be continuing to use the same synthetic but going down to 32:1 for 3 or 4 trips and see if I notice any difference. I will be tearing down also to measure for wear and inspect for buildup in exhaust port.

Remember any changes in mixture must have jetting adjusted accordingly since more oil in mixture means less fuel hence a leaner mixture and vice versa.

[asdf450r]

i dont personally own a 250r or any two stroke bike for that matter, but wouldnt more oil mean more lubrication which = a cooler engine and less wear? :confused:

[baker250r]

yea, but more of a dog.... and less power therefor

[bcox]

more oil means better ring seal = horsepower

I run mine at 32:1....

I am trying a new oil out...anyone run Redline oil before?

[zedicus00]

more oil = less gas therefore less power.

[bens250ex]

im so freekin confused..i just got my r runin and i ran it with 32:1 what oil should i use???

[trailgoon]

Ive ran the R that I ride on MC-1 since we got it in 1986. We just rebuilt it last year and it was still running great! The main reason we rebuilt it was to see if it would get rid of the classic R "rattle"

[JTRtrx250r]

Originally posted by bcox
more oil means better ring seal = horsepower thats not legit dude, more oil = a hotter motor... which in turn dont last as long(there are too many variable factors)

a cooler running motor is healthier, more fuel = a cooler motor which means when jetted right=more power!

the GAS DISPLACES THE OIL... only thing you have left is AIR ...we all know what happens w/ too much air and not enough of the other factors:eek2:

The richer the motor... the more HP it will make under load, oil dont make it ricker... gas does!;)the oil just lubricates, if its too fat... you loose the plug! or wont make any power

For those who dont follow... look at your Ratio-Rite, and tell me... what has MORE oil... 20:1 or 40:1

and before you start trippin'.. remember THE OIL DISPLACES THE GAS IN THE MIX, GAS IS WHAT COOLS, OIL IS WHAT LUBES!

whats gonna take its place in the volume, its gonna be too much.. or not enough of the other.. right?


If you know how to jet, you can actually jet the carb to run any mix, motor life is another story;)

Bens... just run it at 32:1, and jet the carb curciuts accordingly;)

Conditions, weather, riding abilty, riding style, motor specs etc... all play their part, thats what every motor runs diffrent w/ a diffrent rider

example, a woods motor is TOTALLY diffrent than a flattrack motor, you'd be fouling out plugs trying to run a flattrack motor in the woods, and you'd smoke a woods motor on the flattrack, thats why each has its own, just like "to each his own":D

[elchankoblanko]

well said JTR

[Meat]

Originally posted by elchankoblanko
well said JTR

Agree, JTR is on the right track here.

Guys don't get oil\fuel ratios confused with air\fuel ratios. Your air\fuel ratio can be dialed in for any oil\fuel ratio. You should mix your oil\fuel ratio by two rules of thumb, first being... mix the oil amount recommended by the oil manufacturer, second rule of thumb is... a small cc engine(80's and 125's) should get a lower ratio(20\1) compared to a larger engine(250's and 500's) that should get a higher ratio(32\1 or 40\1 or whatever)

If your oil bottle doesnt have a recommended mix ratio, then you need to consider what size engine you have and mix accordingly. If your riding a 250r and your oil company doenst have a recommended mix ratio, then mix er up at 32\1, jet it for 32\1 and you'll be good to go.

Remember....
Adding more oil added to the gas without jetting changes will cause your engine to run leaner.
Less oil mixed with your gas, without any jetting changes, will cause your motor to run richer.

Remember....
Gasoline cools your top end and does not lube it.
Oil lubes the top end and does not cool it.

[bens250ex]

so what would be a good combo for cooling and lubing the best? im going to be running mx, back yard play, and the dunes for 2 trip... and maybe alittle flattrack

[jokerman_28]

i ran amsoil 40:1 in my old 250r. i run amsoil in everything i have.

[beerock]

I run amsoil at 50:1

[Meat]

bens250ex, running 32\1 is prolly the most common mix ratio for oils without a recommendation on the bottle. Mix er up at 32\1 and dont forget to check your jetting.

Im also an Amsoil user. 50\1 ratio. Been using it for a coupla years now and NEVER have any engine problems or foul any spark plugs. Its the shizznitt !

[hontrx265r]

I've built and raced many R's and also blown up many. The best way to go is 32:1 maxima 927 or something equal. And do your self a favor and never run a k&n, there crap always run a uni or sometype of foam filter with filter oil not motor oil you'll have the best luck with reliabilty and your performance will not suffer, besides a running quad is better then a non running one.

[zedicus00]

theres nuthing wrong with K&N, ive used them mfor years. oil it right and run a waterproof outewheres if you dont hav an air box.

i run golden spectro at about 40:1 its always dun me good. may try going 45 or 50:1 this season just to see.

[Roostin250R]

"MC1 at 50:1 is a much fatter(richer) ratio than
32:1"
Actually 50:1 is leaner not richer than 32:1 :)

[zedicus00]

it depends on rather yur talking about the airfuel ratio that occurs when you add more oil which would be leaner. or the oil fuel mixture which would be richer. start at the begining and reread this whole thread.

[TRX_250r18]

do whatever you want just try and find the best mix like i use to use 32:1 but i do 40:1 now because it seems to run smoothest that way and my jetting is perfect for my riding conditions where i live
and also make sure you airfilter is always extremely clean

[Thumperz4Life]

HONDA HP2 @ 32:1 W/ VP110

[beerock]

Originally posted by Roostin250R
Actually 50:1 is leaner not richer than 32:1 :)

its richer, there is more GAS per cubic inch in the tank with 50:1 then 32:1

does that make sense to you now??

i mean think about it. if you pour 32:1mix into a 5 gallon pail, and then a pail with 5gallons of gas in it and throw a 50:1 mix of oil in it, what will be higher in the pail the 32:1 or the 50:1?


the 32:1 hense a leaner fuel condition.........

and since the 50:1 has less oil, its a rich condition.......

[Meat]

Guys don't get oil\fuel ratios confused with air\fuel ratios.

Ahem... ;)

[JTRtrx250r]

Originally posted by Thumperz4Life
HONDA HP2 @ 32:1 W/ VP110 STEALTH my brutha!!:D :cool: :macho

[Roostin250R]

"Guys don't get oil\fuel ratios confused with air\fuel ratios".

Yes I think we were talking about 2 different things :(

[JTRtrx250r]

I dunno about you guys, but 99% of the posts I read .. make me cringe and think " that poor motor :( "

[Roostin250R]

Good thing we got you here huh :p

[JTRtrx250r]

Originally posted by Roostin250R
Good thing we got you here huh :p Me? , I just try to help in any way if I can, I definitly dont mean to sound like a know-it all, b/c I sure as hell dont:p

Really dont mean to offend anyone.., I just really like to interact w/ fellow R riders, or any for that matter

I was just saying... sometimes I read a post (usually a nood to the scene) and think how much bad they are doing , or how much more the motor might like me instead LOL

I honestly dont mean to piss in anyones cornflakes, or think Im some kind of R specialist either so I hope you dont think that:ermm: its just 1 of my hobbies too..

[Roostin250R]

Dude I was just messin with ya, I enjoy reading your posts very informative. :)

[JTRtrx250r]

k...cool!:D :cool: haha

[ground_zero298]

I'll throw my 2 cents in. I race alot of rc cars along with riding. More oil the cooler the engine runs. 20:1 will run cooler than 32:1. Does not means it runs better. And also 50:1 is a lean mix 20:1 is a rich mix. Their is no fat mix. If you don't believe me get your self a temp gun and run both mixtures. Take temp off the side of the jug. I still run 20:1 in my 89 trx never had any plug fouling or problems.

[wilkin250r]

I hate to tell ya, JTR, but you're wrong.

Many studies done by people much smarter than you or I will confirm, more oil means more horsepower. No, it's not a jetting issue, the people performing the tests adjusted jetting for each mixture. And these people were experts, I have to believe they knew how to jet, so I have to believe the results are accurate.

I don't know the exact reason behind it. Some say cooler, some say less friction. Me personally, I think the heavy molecules of the oil create more power when they burn. Regardless, it has been proven over and over, a 20:1 mixture will make MORE power than a 50:1. In fact, they noticed an increase all the way down to about 8:1, until the oil began fouling spark plugs.

Try a web search, you'll find it.

[JTRtrx250r]

Originally posted by wilkin250r
I hate to tell ya, JTR, but you're wrong.

Many studies done by people much smarter than you or I will confirm, more oil means more horsepower. No, it's not a jetting issue, the people performing the tests adjusted jetting for each mixture. And these people were experts, I have to believe they knew how to jet, so I have to believe the results are accurate.

I don't know the exact reason behind it. Some say cooler, some say less friction. Me personally, I think the heavy molecules of the oil create more power when they burn. Regardless, it has been proven over and over, a 20:1 mixture will make MORE power than a 50:1. In fact, they noticed an increase all the way down to about 8:1, until the oil began fouling spark plugs.

Try a web search, you'll find it. wilk....:rolleyes:
You go w/ what you want!

[hollywood250r]

Originally posted by wilkin250r
I hate to tell ya, JTR, but you're wrong.

Many studies done by people much smarter than you or I will confirm, more oil means more horsepower. No, it's not a jetting issue, the people performing the tests adjusted jetting for each mixture. And these people were experts, I have to believe they knew how to jet, so I have to believe the results are accurate.

I don't know the exact reason behind it. Some say cooler, some say less friction. Me personally, I think the heavy molecules of the oil create more power when they burn. Regardless, it has been proven over and over, a 20:1 mixture will make MORE power than a 50:1. In fact, they noticed an increase all the way down to about 8:1, until the oil began fouling spark plugs.

Try a web search, you'll find it.

With more oil on your fuel you get a better ring seal/less blow by. That is the motor will make more power with a 20:1 fuel mixture over a 50:1 fuel mixture.

[86-250Rnut]

I ran amsoil 100:1 ratio in my 250R for a while. but i jumped it down to 50:1. but i still run 100:1 mix in my dirtbike. i have had it for 4 years and only blew 2 pistons out of it. and i ride the thing every day. so i feel 100% safe that the engine wont blow at a 100:1 ratio. i know alot of you think im dumb for doing that but you dont see me burning pistons like alot of guys are with a 32:1 or even 20:1. 50:1,80:1 or even 100:1 is the way to go if you run synthetic oil.


amsoil for life!

[ground_zero298]

The thinner the mix the faster your engine will rev. 86-250Rnut did you notice any performance difference between the 2?

[86-250Rnut]

Not really.

[wilkin250r]

Originally posted by ground_zero298
The thinner the mix the faster your engine will rev.

What's your proof?

[ground_zero298]

Well from runnin rc cars which run extreme rpm up over 30000 on a good motor, When you have oil in your gas when it burns the some of the oil stays behind. If the mix is to rich you will get oil build up or excess oil if you will, Making the piston seal much tighter. Oil does not compress. The less oil you run the faster the engine will rev because theirs less resistance in it. Now who can say which is better, I don't know but in the rc world the faster your engine can spool up the better. In the cars you thin the mix out until it detonates or it runs to hot, from lack of oil. And also the oil does cool your engine internally. But hey thats what me and the guys runnin at the kyosho open say, if 250r 2 strokes work differently like water swirls backwards in australia foregive me. Seem like every ones about puttin faster parts on their bikes instead of optimizing the stuff you take for granted which can make your bike alot faster like the right fuel ratio. That just what I think. If it seem like my head shoved to far up my ***** then hey, stick your up here to and see what i'm seein. And I'd like to see to identical r"s runnin 8:1 and 50:1 race. I'll put my slip on the 50:1. Just for fun somebody run a 8:1 mix and see how it does,

I'm not wasting a gasket on that bs

[wilkin250r]

Ok, I'll agree. However, I don't think you can make a direct comparison between 2.5cc RC nitro engine turning up to 50,000 rpm, and a 250cc ATV engine running 10,000 rpm.

For one, the small mass of the piston in the RC engine, combined with the extremely high RPM range means that any restriction at all to the piston movement is very difficult to overcome. However, the piston in the 250cc engine is roughly 1000 times heavier, and moving much more slowly. The viscosity and resistance of the oil on the cylinder walls is MUCH less significant, nearly inconsequential.

It's like comparing the effects of air resistance between a bullet and a bowling ball. Air resistance has a HUGE impact on a bullet fired out of a gun, and any changes have a drastic effect on the range and accuracy. However, air resistance doesn't matter much at all to a bowling ball. You can double the air resistance, and it will still travel down the lane at the same speed and knock over the pins with the same force.