Fuel Mixture 2 stroke oil mixture

[Fabian]

yes, i have done that before (straight diesel) in a whipper snipper or as Americans call it, a weed wacker.
I needed to start it by having the absolute smallest amount of 2-stroke petrol mix in the fuel tank to get it running, then when hot, i would fill the tank with straight diesel. It smoked like crazy, but it ran perfectly ok on straight diesel, with similar rpm to running it on petrol, though i had to readjust the mixture screws for straight diesel, and readjust them back to start it on petrol.
There was seemingly no damage to the engine after i stripped it down to see how effectively the diesel lubricated the engine.

 

[Fabian]

I've had good success with 25:1 oil/fuel ratio from beginning to end and i use 20:1 when i'm going to be doing serious heavy duty haulage at low speed.

I've never subscribed to the gentle break-in procedure. I've run all of my bicycle engines at virtually 100% duty cycle from the word go, same as with every car and motorbike and boat i've owned, and it seems my engines always go better than friends who use a gentle break-in procedure, or manufacturers recommended method.

 

[RawRawRaw]

So you're saying If we have a 'starter bottle' on our bikes with oil+fuel 20:1, add about 200ml of that, then after 5 min when it's heated, pour 1.5L of diesel, and it will run just fine?!

 

[Fabian]

I most certainly wouldn't run my bicycle engine on straight diesel, for three reasons 1) it will totally smoke out the neighbourhood in 30 seconds. My house and garden were covered in white diesel smoke from a 30cc wipper-snipper/weed wacker running on straight diesel and 2) pump grade diesel is not engineered to be used solely as a lubricant and 3) the ignition timing is optimised for petrol, not diesel.
It ran fine when testing to see if the idea would work, but it was just a test, and it did indeed work surprisingly well.

A point to note is that the wipper-snipper i ran on straight diesel never had the opportunity top be sufficiently loaded up to test the power band efficiency compared to petrol.

Back in the old days there was a German engineer who designed a diesel injection and ignition system to operate as spark ignition on a conventional low compression engine design.
Diesel fuel when finely astomised can be ignited by a spark.

The hessleman Engine:

http://en.wikipedia.org/wiki/Hesselman_engine

http://www.smokstak.com/forum/showthread.php?t=67411

http://forum.woodenboat.com/showthread.php?58307-The-Waukesha-Hesselman-Low-Compression-Spark-Ignition-Oil-Engine

 

[Purple Haze]

A lot depends on the fuel, don't know what you have available, but here in the states it is hard to find 100% petroleum gasoline. The more ethanol in the mix, the less efficient the oil becomes. I run 32:1 all the time with no problem, but I try to always run gas without any ethanol, and at least 91 octane.

 

[Samdallas214]

Fabian is right 100 % diesel is not the way to go , unless you want to get rid of flies and mosquito's, then the smoke caused by the diesel would do the job, down side is it would also get rid of you to, stick with a mixture, I tried it once on a weed wackier smoked so bad you could not see the weeds, to cut them down, worked great to on the flies and mosquitoes. LOL

 

[RawRawRaw]

What about used cooking oil? We need a guide to make the ultimate post-collapse gas powered zombie killing machine!

 

[Fabian]

cooking oil - diesel - just about the same thing if you can atomise the liquid and get enough heat into it.

 

[beetlefarm68]

I use Lucas Oil Semi Synthetic 2-Cycle Oil

I use Lucas Oil Semi Synthetic 2-Cycle Oil 8 oz to a gl 16:1(one cup) been doing this for over 3 years very little smoke would I get more horse power using more oil? the spark plug shows no oil at all I'm running a cns high performance carburetor with a expansion chamber (banana exhaust) on a 66cc and what mark should i put the carburetor needle at there are 5 markings on it

 

[Fabian]

You can safely run leaner than 16:1 oil/fuel ratio.

25:1 is a nice balance between lubrication and heat extraction and a hydrodynamic barrier between piston rings and cylinder wall.

20:1 is a better ratio if working the guts out of the engine at low bicycle speeds, with negligible airflow over the cooling surfaces.

16:1 is specified when you don't have access to a dedicated 2-stroke oil. Basically at that ratio you can throw any kind of oil into the fuel, so long as it will mix together.