Fuel/Oil mix

[begleytree]

Walker,
nope. no scans. no nothing. no proof, just like you.
I'm outta this, remember? We just disagree, only I don't know about what, you never even approached the subject at hand, nor offered any proof of your statements.
My manual says 50:1 on the bike, believe it or don't, I don't care.
I have to make money off my saws, so I choose to rely on the saw designer's info as to what mix they designed the saw to run on. You do whatever you want.
-Ralph

 

[Crofter]

If a piston and cylinder has a bit of wear or is loosely fitted, extra oil will reduce leakby during compression which will give a higher effective pressure. (It doesn't affect theoretical compression RATIO) It will also do a great bit toward increasing base compression / vacumn which is only sealed by the piston fit in the bore. (I wonder if this is a factor in the higher output observed on some tests with 16 to one mix)
I think the questions valid about how oil affects the burning characteristics of the fuel. Even if the mean temperature of two different fuels be the same, different colours of flame and burning rate can affect their heat and pressure inputs.

 

[bwalker]

It has been well documented that more oil increases power. Even on new engines. Mac authored a SAE paper on this in the 70's.
Begley, How much do you want to bet your 25or manual does not reccomend 50:1. Specificly what do you want facts on?

 

[Crofter]

Ben I have seen the data somewhere too on that 30 year old expeiment, but I would like to see it repeated with a modern saw engine with factory clearances and see if it still holds. Maybe when Timberwold gets his dyno cobbled up he can do a test. Momentary maximum output means nothing if it is not sustainable and livable from a maintenance and user friendly viewpoint.

" We argue, not that I may triumph over you, or you over me, but that through discussion we may arrive at a more perfect truth! "

Aristotle

 

[Gypo Logger]

If a piston and cylinder has a bit of wear or is loosely fitted, extra oil will reduce leakby during compression which will give a higher effective pressure. (It doesn't affect theoretical compression RATIO) It will also do a great bit toward increasing base compression / vacumn which is only sealed by the piston fit in the bore. (I wonder if this is a factor in the higher output observed on some tests with 16 to one mix)
I think the questions valid about how oil affects the burning characteristics of the fuel. Even if the mean temperature of two different fuels be the same, different colours of flame and burning rate can affect their heat and pressure inputs.

Frank, that's exactly what I was going to say.
If a fatter mix increases compression and therefore power there must be an optimum ratio at which power is at it's highest and residual oil and carbon is at it's lowest.
John

 

[Crofter]

Gypo, probably each engine has its own sweet spot and that too, dependant on how the operator uses it.

 

[begleytree]

Ben, LALALALALALALA, I can't hear you!!!!!!!!!
Look up daggers posts, thats all you need to know
Again, I'm outta this. Took the dog out of the fight, took the spurs off the chicken.
Agravating you is much more fun than discussing topics. All in fun of course, not looking to kill anyone.
-Ralph

 

[LJS]

Gypo, probably each engine has its own sweet spot and that too, dependant on how the operator uses it.

That's what Gypo's "old" girlfriends used to say too, Frank!

 

[Crofter]

He told me he regretted no being bilingual!

 

[rahtreelimbs]

but none the less he's still a cunning linguist.

Knocking at Your Back Door.....from 1984's Perfect Strangers
(Blackmore/Glover/Gillan)


Were something in diplomacy
So we put her on the hit list
Of a common cunning linguist
A master of many tongues

 

[Crofter]

And to think I accused FISH of being perverted! Cod liver oil is better than dinosoar or synthetic ( just as a concession to being on topic) It is a great souvenir when you get it in your moustache

 

[WRW]

Dagger's knowledge was circa the 70's. QUOTE]

 

[Gypo Logger]

Yup, nothing quite like those furry chainsaws.
John

 

[glens]

" We argue, not that I may triumph over you, or you over me, but that through discussion we may arrive at a more perfect truth! "

Aristotle

The last phrase of that quote is often left out, as Frank has shown it.  It ends with "and so that you'll know I was right".

In respect to being cunnilingual, it's really a situation-ethics kind of thing...

Glen