2 Stroke oil in 4 Stroke gas

An A rider told me today that he puts a little two stroke oil in his gas for his four stroke to help with the valve life. It kind of makes sense to me, even though it goes against the right thing to do, it should help keep the valve guids lubbed up nicely. Just wondering if anyone has heard this before or knows any negative effects it could have on the motor.

ive heard of it before, sounds legit if your not doing it constantly

The negative is excess carbon buildup on the valves. And what causes the valves to wear? Dirt and carbon. I'll stick with my straight gas thanks. I hear of more valve wear issues than guide wear issues. Though I do run 2smoker gas in my lawn mower occasionally if I run out of regular.

91 octane pump gas straight in my bike. I don't think its that great of an idea running 2 stroke oil in your four stroke, whatever the mix.

91 octane pump gas straight in my bike. I don't think its that great of an idea running 2 stroke oil in your four stroke, whatever the mix.

also agreed.

Well. Carbon buildup, how does that wear the valves? And as it lubes the guides it also cools the valves. I think it's good idea, I've had it in mind for a long time. Or put som ... Led? Like in old cars.

everyone likes to bash an idea that they have no experence in. ive run strait 2 stroke mix in my crf for a tank and had no problems, didnt notice any power loss. I cant see a little 2 smoke oil hurting anything.

Has your mower ever had valve problems? :thumbsup:

It's two stroke oil for a reason....because it's for two strokes. I'm no expert but it makes sense to me:excuseme:

Don't be bashing agentsmith. He is a very reputable mechanic/machinist.

Pffft, come on some yahoo on the internet said it so it must be true! I've got another performance tip for you guys, but don't tell anyone. Run straight avgas in your two-stroke. Adds 3hp! You'll be amazed!

IMO, If your going to add something to the fuel use a product that's designed to be top end lube and use only as directed. Two stroke oil has too much heavy fractions of oil that can leave carbon. The top end lubes usually leave a metallic ash than can transfer heat, maganese, sodium, phosphorus for example, and just use a light oil/solvent mix for a carrier.

Used just cap full of syn two stroke oil in my touring bike each fill on a trip once as an experiment. There was noticable soot at the tail pipe outlet even with this small of dose.

All that said, the exhaust valves run way hotter than the intakes? and they don't seem to have the problems. Heat is a factor, but there is more to the intake problem than heat transfer, IMHO.

I think you would see more benefit from using leaded gas than the two stroke oil. The 2 stroke engine is designed differently and it requires this oil, if the 4 stroke engine was designed to have oil in the gas, they would have told you to put it in there.

I believe this is one of those old wives tales.

i'm not going to bash your idea, but i will give you MY logical opinion. they call it 2-cycle mix for a reason. if it doesn't hurt your bike now...thats a good thing....if your bike sucks a valve or one hits the piston in the future and you find it to be because of valve falure or stress, at least you asked and got opinions on running 2 stroke gas in your high performance 4 stroke.

I would say that there's never too much lubrication. But my idea involved 2-stroke oil, but also to use leaded fuel instead of oil. The lead in the fuel might have a good effect on the engine.

And as someone said, if heat would've been the leading factor in killing valves, the exhaustvalves would go quicker even though it's steel. What kills the valves is as most of you know is dirt and such in the intake mixture.

And carbon comes to a certain point, like when you get a bad valve seal.

Just ideas. But i'd love to research on this to gain some facts, but not on my own race bike. :thumbsup:

I would say that there's never too much lubrication. But my idea involved 2-stroke oil, but also to use leaded fuel instead of oil. The lead in the fuel might have a good effect on the engine.

And as someone said, if heat would've been the leading factor in killing valves, the exhaustvalves would go quicker even though it's steel. What kills the valves is as most of you know is dirt and such in the intake mixture.

And carbon comes to a certain point, like when you get a bad valve seal.

Just ideas. But i'd love to research on this to gain some facts, but not on my own race bike. :ride:

putting anything in you racing 4 strokes fuel is wrong, ----oil and or adding additives will only add in making more engine dirt and help RUIN YOUR SEATS AND VALVES.-------not to mention your loss of ring seal and help contaminate your lower end, crank , bearings and so on.

additives , and oil adding in you fuel also lowere the octain in the fuel ,

it is very hard to get a good ring seal in a motor any way,------and it is hard to keep a combustion chamber clean , flowing correctly and making power when its all assemblied correctly anyway ,

adding anything in your 4 strokes fuel is a loosing proposition all the way around .

its just like mixing fuels ------you ruin both fuels when you mix any fuels.

just run clean unleaded fuel ------or 4 stroke racing fuel all straight in your racing 4 stroke .

:thumbsup:

There's an entire science to top end lubrication. I've been around several different types of racing and guys running sprint cars and guys running 4 stroke karts. Some ran top end lubricants some did not. Those that did said that the top end lube would help seal the piston rings and therefore help maintain compression and HP. Another thing to consider is these guys rebuild engines almost as often as we change oil. I do not run top end lubes.

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