2 stroke mixed fuel in a 4 stroke

[fastfredracing]

I bought a cheapo chineese quad last weekend barely running for $200.00. My parts came in yesterday, and I put it back together. My neighbor stopped over and watched me pour in a gallon of gas from my can marked " Chain Saw". He flipped, and looked at me like I grew a third eye. "I would drain that out, I would not run on that fuel, o.k. you do what you want, it's your quad. "
I have done this for years, having grown up on dirt bikes , there was always pre mix around, and if the lawnmower was low, or I need some gas in my car, I would burn up the extra pre mix.
Whats the worst possible thing that could happen? A few more deposits on the valves, a fouled spark plug? I have never had any problems, or noticed any extra smoke, but the lawnmower used to smell like golden spectro, or bean oil.

[Tim Hancock]

If it fouls plugs, drain most of it out ....... if it does not foul plugs.... ride it.

I have dumped "old" premix in my cars/mower/tractors to get rid of it when it was too old to trust in my ultralight. Never had any problems.

[ben parrish]

Not an issue...

[sammyg2]

BTDT, never had a problem. That is if you doan mind yer lawnmower smelling like castor beans

Ahh, I long for the old days when we still burned castor-based two stroke oil.
Back in the early 70's there was nothing cooler than riding at saddleback motorcycle park, smelling the oil.

If you were there you'd remember.

[BeyGon]

couldn't make it over the top of the Matterhorn with my track Bultaco but I did go off the top and make it down once. My buddies asked me if I was going to do it again, Hell No. Free fall for awhile.

[Hugh R]

I wouldn't do it with a car with a cat that you have to smog.

[Zeke]

The specific gravity (I think that's the term) of gas with oil in it might make the mixture leaner. But that might be a good thing to burn the oil. I put some 2-cycle racing gas with some "additives" in the 4-stroke lawn mower back in my kart racing days and the damn thing would not bog down in tall grass as it did before.

The "additives" definitely work! (Talking di-nitro propane at 5%, the propylene oxide had already evaporated.) The castor oil also helps and does smell good.

[john70t]

Used a 1(old) to 4(new gas) mix in the powerwasher, and it seemed to run better than straight gas.
Mabye it adds upper-cylinder lube?

[sammyg2]

Originally Posted by BeyGon

couldn't make it over the top of the Matterhorn with my track Bultaco but I did go off the top and make it down once. My buddies asked me if I was going to do it again, Hell No. Free fall for awhile.

I looped my buddy's 250 CZ right near the top where it went past vertical. Prolly the zact same spot you're talking about fee-falling from. tumbled down and cracked the weld where the frame met the head tube.
He was peeed off.
I was too busy pretending like it didn't hurt but I didn't fool anyone, not with that whole not breathing thing.

My Yamaha wouldn't even make it a quarter of the way up that hill.
It was a 125 enduro I converted over to strictly a dirt bike, tried to make it look like a YZ with a plastic tank, fenders, and 21" front wheel. And yeller paint. Lots O'that.
Had a heck of a time keeping up with my brother's CR 250 Elsinore and the CZ, but i didn't care.
Man I loved that place. I was 14 or 15 and my oldest brother took us there at least once a month.
Some of the best times in my life. I remember the jump in the middle of the TT track.
I'd hit it going about 45 and it felt like I flew a mile.
Prolly only 20 or 30 feet but I felt like sammy Knievel.

[Jared at Pelican Parts]

It depends on the ratio of oil used. A little bit probably wont hurt anything except maybe foul the plugs. We actually used to put a little 2 stroke oil in with my friends Mazda RX-7.

I wouldnt worry about it too much, especially in an air cooled motorcycle engine.

[Jared at Pelican Parts]

Originally Posted by sammyg2

there was nothing cooler than riding at saddleback motorcycle park, smelling the oil.

If you were there you'd remember.

My dad raced at Saddleback when I was a little kid. I remember exactly what you are talking about

[bell]

i've always used premix in old ass engines which havent ran in years.....my 350x engine for example, sat under a workbench for about 5 years+ .......put in some pre mix on the first fire up and although it smoked like james bond after about 30 minutes put in some normal fuel and she ran like a champ.......
won't hurt much, will just smoke and probably wont go too good under load......but shouldn't hurt a thing....

[sammyg2]

Originally Posted by Jared at Pelican Parts

My dad raced at Saddleback when I was a little kid. I remember exactly what you are talking about

LOL, thanks for making me feel old....er.

Back when I was your age things were different. We rode barefoot, .... in the snow, .....uphill!

And we were glad to do it!

[sammyg2]

2 stroke oil doesn't really burn during the combustion stroke like fuel does, so it displaces the fuel causing the mixture to effectively a little run leaner.
That's why the old myth about running more oil (like 20 to 1) to break in a new top end actually did more harm than good in many cases.
Iffn you wanted to break it in softly, just richen up the needle for a while. Or build it right so it doesn't need break in, either way

At 50 to 1 or less it doesn't really make much difference as far as rich/vs lean.
If you have 50 to 1 and you mix it with regular gas the ratio gets thinned even more, so it won't hurt anything except maybe a catalytic convertor or an O2 sensor. Prolly not a good idea to run two stroke oil past a wide band O2 sensor. The metal additives in the oil would prolly plate the sensor and shorten it's life. That's just a hunch, no real knowledge on that subject.
I know they really hate silicone..............

I don't even know if they make castor based oil anymore. the new synthetics are soooo much better.
We used to run the castor oil at about 30 to one to keep the top end from hot-seizing and the stuff gummed up the rings so bad we had to go through the top end pretty often.

With the new synthetics 50 to 1 is common and they never gum up and last a long time. They barely even smoke anymore.
If they could only figure a way to make the synthetic oil smell better...........................

[Zeke]

I think castor did burn, that's why it was used. That's what the old fuel wizards used to say anyway. The ones that had a few ounces of hydrazene tucked away for the last heat.

[Jared at Pelican Parts]

Originally Posted by sammyg2

LOL, thanks for making me feel old....er.

Back when I was your age things were different. We rode barefoot, .... in the snow, .....uphill!

And we were glad to do it!

My dad used to ride me around in his lap on his TM400.

[BeyGon]

Originally Posted by Jared at Pelican Parts

My dad used to ride me around in his lap on his TM400.

I raced with one of those set up for short track at El Toro, I think a guy named Jim Black owned it.

[Jared at Pelican Parts]

I rode my dad's TM a few times. Thing is a death machine. I have NO idea how the old timers raced those bikes. My father's next door neighbor growing up was Mark Blackwell. When all the first generation MX guys came over from Europe, they stayed with Mark. There's a picture of my dad hanging out in the garage with Mark, Roger DeCoster and Joel Robert. Later on, my father rode for Van Nuys Suzuki

I grew up around the tail end of all the tracks that were in SoCal. Indian Dunes, OCIR, etc.. My dad had me on dirt bikes (and rebuilding them) from the age of 5. Great memories growing up. The sport was a LOT different before money and corporations got involved. My brother and I rode competitively for a while. He turned out to be much better than I was, sadly. I became the mechanic while he raced.

[LakeCleElum]

Originally Posted by sammyg2

BTDT, never had a problem. That is if you doan mind yer lawnmower smelling like castor beans

Ahh, I long for the old days when we still burned castor-based two stroke oil.
Back in the early 70's there was nothing cooler than riding at saddleback motorcycle park, smelling the oil.

If you were there you'd remember.

I remember the smell of the Castor Bean oil very well....During the winter, when I couldn't road race my RD400, I'd put bean oil in the fuel tank of my 4-stroke street bike just to enjoy the smell at the stoplights.......