Fuel Mixture 2 stroke oil mixture

Discussion in '2-Stroke Engines' started by orbeas, Feb 7, 2013.

  1. orbeas

    orbeas New Member

    The instruction book with my engine says run with a 16-1 mixture, what mixture are you using as 16-1 is a lot of oil in the mix..
    look forward to your thoughts !!!

  2. Samdallas214

    Samdallas214 Member

    32 to 1 first 100 miles
    20 t0 1 after that, is what I would use
    And welcome to the form
  3. Dankoozy

    Dankoozy Member

    If its 16:1 in the book thats what I'd put in there. The book is there for a reason

    I have some 2 stroke engines that use 50:1 (most common these days), 40:1 and 25:1. I know of kart engines wanting 18:1 but these are very high revving race engines. What kind of an engine is it you're using?
  4. Skyliner70cc

    Skyliner70cc Active Member

    32:1 to start and thereafter. 16:1 is way too rich with oi and the "book" is written by Chinese who use motor oil not 2 stroke oil in their rides.
  5. Dankoozy

    Dankoozy Member

    Motor oil instead of 2 stroke.. barbarians!

    I suppose if you bought a chainsaw off those guys the oil pump would be calibrated for honey and not chain oil.
  6. geebt48cc

    geebt48cc Member

    Whatever combo you come up with, but be sure to add 25% of the ratio with CASTOR oil!!!!!!!!!!~ GREAT IDEA!!~ READ about!~
    Last edited: Feb 8, 2013
  7. Fabian

    Fabian Well-Known Member

    and castor oil smells good too :grin5:
  8. donb4103

    donb4103 New Member

    I have used 32:1 for ever on these engines. Never had an issue with that ratio.
    Actually I had one old 2 stroker that I fired up and rode around the block running nothing but diesel in it.
    It actually ran pretty good too. No lube tho!!
  9. geebt48cc

    geebt48cc Member

    Are you serious? 100% diesel? Wow, I believe, but you wouldn't think compression would be high enough. Uno, if these little engines were diesels, then I bet they would last a very long time.
  10. donb4103

    donb4103 New Member

    Well it was a synthetic diesel fuel and the engine was already heated up after running out of the regular gas. Diesel will not normally start in a cold engine. It requires a heated cylinder to combust. So in the real world you could not run it on diesel as an everyday fuel. No way to heat the cylinder. Also not enough oil in the fuel to lube up the moving parts.
  11. Fabian

    Fabian Well-Known Member

    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.
  12. Fabian

    Fabian Well-Known Member

    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.
  13. RawRawRaw

    RawRawRaw New Member

    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?!
  14. Fabian

    Fabian Well-Known Member

    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:



  15. Purple Haze

    Purple Haze Active Member

    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.
  16. Samdallas214

    Samdallas214 Member

    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
  17. RawRawRaw

    RawRawRaw New Member

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

    Fabian Well-Known Member

    cooking oil - diesel - just about the same thing if you can atomise the liquid and get enough heat into it.
  19. beetlefarm68

    beetlefarm68 New Member

    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 :detective::huh2:
  20. Fabian

    Fabian Well-Known Member

    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.