Author Topic: 2 stroke fuel mixture  (Read 30441 times)

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cxs58

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2 stroke fuel mixture
« on: April 10, 2008, 06:38:47 pm »
Don't know if this is the right area for this topic but I need to know what the best 2 stroke oil / fuel mixture is for my 84 Husky 125.
I am assuming that it doesn't vary between motorcycle brands or am I wrong.
I have been told 20:1, 30:1 and 40:1.
I've got no idea - this is my first 2 stroke - so all help would be appreciated.
Craig

Offline holeshot buddy

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Re: 2 stroke fuel mixture
« Reply #1 on: April 10, 2008, 08:09:18 pm »
 40 TO 1 motul 800 will do fine  ;D
follow me to first turn

cxs58

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Re: 2 stroke fuel mixture
« Reply #2 on: April 10, 2008, 08:38:50 pm »
Thanks Russell - much appreciated ..................

Rosco400

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Re: 2 stroke fuel mixture
« Reply #3 on: April 10, 2008, 09:35:45 pm »
40 TO 1 motul 800 will do fine  ;D

40 to 1 maxima 927 smells better, :D

oz555ktm

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Re: 2 stroke fuel mixture
« Reply #4 on: April 10, 2008, 10:34:18 pm »

I still run 25 to 1 Castrol GPS 250cc and 495 but I run 16 to 1 in the 125cc.

If jeted  to this will run find.


Oil is Cheap and so is Muffer packing But Pistons and Rod Bearing are Like Rocking horse Shit

Offline Freakshow

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Re: 2 stroke fuel mixture
« Reply #5 on: April 10, 2008, 10:52:22 pm »
32:1 is the only number i have used on 2smokers unless its the first tank on a piston, and that is regardless of brand of 'normal oil"

err on the little smoky but too much is just as bad as too little, as the oil leans out the fuel also
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Offline Lozza

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Re: 2 stroke fuel mixture
« Reply #6 on: April 10, 2008, 11:14:32 pm »
A very wise and experience 2T tuner told me "Cheap oil at 20:1 is far better than expensive oil at 40:1" and 555 has it 100% correct there, the harder they rev, more oil is needed.More oil makes less heat and more HP. Rossco try Agip Kart(castor synthetic and 1/2 the price of Maxima)
Jesus only loves two strokes

Offline gorby

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Re: 2 stroke fuel mixture
« Reply #7 on: April 10, 2008, 11:42:40 pm »
most oilmix disasters that I have observed,have been because people get the oil amount wrong due to poor mathmatics.

my motto ---keep it simple
30 to one 
take a twenty litre drum put 15 litres petrol and 1/2 litre two stroke oil= easy maths
and that amount is just right for easy pouring out of a twenty litre drum.

we have run this mix in all our bikes(modern and old) using plain old caltex revtex oil and had no problems with component wear or failures

Offline Rossvickicampbell

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Re: 2 stroke fuel mixture
« Reply #8 on: April 10, 2008, 11:58:15 pm »
i didn't answer first up as I knew there were going to be so many different answers - I use Silkolene at 40:1 in all 5 bikes for 3 years now and on every motor inspection everything has been spot on?  And never a fouled plug!!!!!

 ;D

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Offline vandy010

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Re: 2 stroke fuel mixture
« Reply #9 on: April 11, 2008, 02:03:52 am »
i've always run 30-1 but i'm steadily listening/thinking more about running a richer mix.
"flat bickie"

Offline pokey

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Re: 2 stroke fuel mixture
« Reply #10 on: April 11, 2008, 07:06:29 am »
seem to remember the books saying 33:1 for my 240wr water cooled  but as you can fathom.. Oils aint oils.


 Run as much oil as the ignition can burn.

 Id start at 33:1 , do a few laps and see how she ran then gradually bring her to 20:1

 Take note of heat as well as lap times  and  do a few plug chops  to get the best ratio for your bike and riding style.

Oil not only lubricates the goodies it also wicks away massive amounts of potentially damaging heat and as  said , parts for huskies aint cheap.

cxs58

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Re: 2 stroke fuel mixture
« Reply #11 on: April 11, 2008, 07:16:52 am »
Well thanks lads - I am completely fcuken bambuseled.
I'll start at around 40:1 and ween it down from there - hopefully if anyone is going to Nudgee on the weekend you will see me floundering around there.
Appreciate eveything.............
Craig

mx250

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Re: 2 stroke fuel mixture
« Reply #12 on: April 11, 2008, 07:23:28 am »
I saw this thread and knew it was gonna be probably controversial or diverse at least.

I'll tell you what I know about two stroke oils and the ratios  ::).

1/Many, many, moons ago American Dirt Bike ran an article on oils and they scientifically measured performance as it relates to racing two strokes. It is too long ago to remember or act on the specific conclusions but the general points would hold true. There are big differences in the engineering quality of oils, shear strength, wear prevention etc. (but be guided by price). Oil ratios weren't critical until into the extremes of the range, high and low, are reached. Too much oil can cause seizures :o because oil burn hotter than petrol (their conclusion not mine - could also be caused by varying the ‘effective’ jetting ratios).

2/ A friend, who was a motorcycle mechanic and an old two stroke racer, went racing 100cc Clubman go-karts. To gain competiveness he had a specialist rebuild and ‘blueprint’ his motor (and yes, I was surprised too). Part of the blueprinting was his particular motor was put on a dyno and the oil ratio was varied until they got the best HP, a 2 HP gain. And that’s what he ran.

My conclusions. Oil ratios are like jetting, you can muck with them and get advantage but you better know what you are doing. And you better be prepared to be pedantic, thorough, constantly making adjustments, be prepared to get it wrong and suffer all the consequences e.g. $$$$$’s.

Me. I run 24:1 on any quality oil, conservative jetting and concentrate on fitness, suspension, good riding, good lines, pacing myself, controlled aggression and having fun.  ;D

mx250

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Re: 2 stroke fuel mixture
« Reply #13 on: April 11, 2008, 07:27:01 am »
I am completely fcuken bambuseled.
I'll say  ;D

I'll start at around 40:1 and ween it down from there
Start at 24:1 and ween down from there if you must  ;).

All Things 414

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Re: 2 stroke fuel mixture
« Reply #14 on: April 11, 2008, 07:50:58 am »
I've ran Silkolene or Motul at 40:1 in all my oldies and had no trouble. My 390 (with an internal fly-wheel and 40 mm carb) motor revs very hard and still had no probs with lubrication.
« Last Edit: April 11, 2008, 08:14:29 am by All Things 414 »