Fuel mix preferences

[thutch85]

I recently started running Motul 800 racing 2-stroke oil (mixed 50:1) and Maxima High Test octane booster (2oz per gallon). The saws seem to be loving it! Starting easier and running stronger in cuts. Thought we'd see what others prefer!?!

[Woodcutter_Mo]

 I just use Echo Red Armor, Echo Power Blend, Husqvarna XP oil, or Stihl Ultra HP. I have a gallon of Red Armor oil so I'm set for a while, it seems to run great and is easy to see the red dye in the mixed fuel. I run 50:1 with 91 octane non-ethanol gas.

[Al_Smith]

 8) Oh goody the great oil debate again .

[sablatnic]

Aspen alkylate premixed petrol.
Because it doesn't stink, and because it can be stored for years.

[ButchC]

I run Stihl Ultra and have the most sound reasoning for doing so. I like the smell of it  :D Secondary is that I haven't had any mechanical issues while using it.

Wife went to work at a fuel depot and they sell fragrances to add to your fuel, that was a new one on me?. I bought the Apple smell and put a dab in the snowblower to test it. Smells like it is running on Apple cider.  I think I will add some to the premix jug ;D

About forgot, my saws all like 91 octane fuel

[Woodcutter_Mo]

8) Oh goody the great oil debate again .

I was going to say, there are alot of oil and mix fuel threads  ;)

[mad murdock]

for over a year now I have been running nothing but amsoil sabre 2 full synthetic 2 stroke oil, at the "sabre' ratio of about 85 or 90:1 in my Husqvarna 395XP and my other saws, and have had no issues.  I have milled about 40k bd ft to date with the sawmill saw (395), and it is running very strong!  FWIW.

[thutch85]

8) Oh goody the great oil debate again .

I searched two stroke oil, oil fuel mix, and chainsaw fuel and didn't find much on fuel mixes. Wasn't supposed to be a debate, just a sharing of info from personal experience, kind the point of these forums. I'd never heard of "Aspen alkylate premix" before, or the apple scented fuel additive. Thanks for the ideas guys. 

[Woodcutter_Mo]

 I've heared of scented fuel additives for the RC cars that run on the nitro methane stuff, never for a chainsaw though  ???

Never tried an octane booster in the 2 strokes. I may try it in one of my older saws and see what it does.

[thedoublejranch]

I recently started running Motul 800 racing 2-stroke oil (mixed 50:1) and Maxima High Test octane booster (2oz per gallon). The saws seem to be loving it! Starting easier and running stronger in cuts. Thought we'd see what others prefer!?!

We raced motocross for years and would use Motul 800 also (this was what most 2 stroke racers used). Another nice smelling oil, more like perfume was Klotz, cool stuff. They also make race fuel.
http://www.klotzlube.com/small_maintenance_.html
Grab some of that gas Home Depot sells, its actually race gas, you saw will perk up, buy it by the gallon for best value, it pencils out to about $100 for 5 gallons, about the same as race fuel. Comes in qts too, I use the qt bottole to haul in the woods, refill from gallon can. Has stabilizer in it, no alcohol, higher octane too. Smells like the race track too.  ;D

We ran 44:1 or 3 oz to a gallon, 50:1 is about 2.6 oz to a gallon and 40:1 is about 3.2 oz to a gallon.

OK, this below is intended for only those who like to extract the extra power available, especially if you run higher octane fuel. If your not interested, then stop here!
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To get the most out of higher octane, we run our "squish band" at about .028" of an inch. This is the area of the piston outer edge to the head surfacde called squish band. We would measure it over the wrist pins space from piston top to cylinder. We measured it by inserting a small chuck of solder, bend it through the plug hole, over the wrist pin area (stay out of the transfer ports or you will shear the solder off) and then roll crank/piston over TDC back and forth, squish solder, remove solder, measure it. .026" was about minimim, after than, you start losing that pop ie diminishing returns. We woudl shoot for .028ish. Of course, we set this with cylinder gasket thickness then timing was set at 1.1mm BDTC. Dial indicator from Motion Pro to do this, fit in plug hole. Of course, dremel to clean up ports, not smooth, just get rid of turbulence or eddies, as for exhaust, polish those.  ;D

[thutch85]

$100 for 5gallons!?!  lol. I've seen VP fuels in 40 and 50:1 premix at 93octane for 20 a gallon. Figured I'd try high test in premium gas to get the octane up close to 100 and save $. In my racing days if you ran high compression you shot for 100octane. Motul, klotz, and maxima were all popular. Went with the maxima high test because it's safe in 2 and 4 strokes.

[sablatnic]

Been out checking the local prices.
Aspen is $17,58 a gallon (US gallon & dollar).
Gas from the local gas station is $7.47 a gallon. (And that is cheap).

[ButchC]

Don't worry about it, your fine. Some of these guys have been around saw forums for quite some time and there has been some pretty long winded (stupid if you ask me) threads about the subject and people posting lots of stuff like run my oil n mix or your saw will glow red, explode and kill half the earth's population when it does so.  Bottom line is no differant than any other information you get from the internet, throw out the extremists, absorb wgat seems to make sence, check the manufacturers  specs and go with it and you will be fine,. There ain't any bad oils, just missapplied oils.

8) Oh goody the great oil debate again .

I searched two stroke oil, oil fuel mix, and chainsaw fuel and didn't find much on fuel mixes. Wasn't supposed to be a debate, just a sharing of info from personal experience, kind the point of these forums. I'd never heard of "Aspen alkylate premix" before, or the apple scented fuel additive. Thanks for the ideas guys. 

[dgdrls]

semi or full Synthetic oil, usually Husky.  I have used VP fuel in the past, nice stuff
but I don't run my saws enough to make it pay. 
I keep fresh non-ethanol mixed in small batches

When I ran my Trials Bike then yes Motul oil and octane booster.

D

[John Mc]

8) Oh goody the great oil debate again .

I searched two stroke oil, oil fuel mix, and chainsaw fuel and didn't find much on fuel mixes. Wasn't supposed to be a debate, just a sharing of info from personal experience, kind the point of these forums. I'd never heard of "Aspen alkylate premix" before, or the apple scented fuel additive. Thanks for the ideas guys. 

Try searching for "oil wars", since Al can usually be counted on to make that comment in every thread where the great debate about what oil mix ratio comes up.

[PNWRusty]

I just run what the manufacturer of the engine recommends. Works for me but I've only been using a chainsaw for the last 42 years so maybe I'm being foolish.

[Gearbox]

When you add oil you raise the octane rating . Just guessing here but 93 octane at 50 to 1 maybe near 100 when mixed . The one reason I run Amsoil sabre at 50 to1 is it chases the Mosquitos away . [ It works try it ]

[thutch85]

Two stroke oil actually decreases the octane rating a couple points. Google it, all the major 2 stroke engine manufacturers say a 50:1 mix drops it about 2 points. Saws are fairly high compression and air cooled so higher octane is good for performance and engine longevity.

[John Mc]

All octane does is prevent the spontaneous ignition of the fuel-air mixture as it is compressed. This higher the octane, the more you can compress it without it self-igniting. The higher your compression the higher octane rating is needed. As long as the octane is high enough to prevent self-ignition, you gain nothing by boosting it further. A couple of points as a safety margin makes some sense (especially since gas tends to lose some of its octane rating over time, as some of the components evaporate off), but running 100 octane fuel in a stock saw does not get you anything in terms of increased performance.

[Gearbox]

I can't see how oil added to the gas will lower the octane rating . I should slow the burn . Maybe it leans the mix . I am no expert .

[Al_Smith]

Some might say it leans the mix .However it's the ratio of fuel,meaning the fuel mix to air .Using that reasoning it would make sense to use straight gasoline and we all should know that won't work .--just saying---

[barbender]

I've seen that reasoning before, Al, and it makes me think of all the saws I've seen that were lean seized from running a heavier oil ratio (zero)🙄🙄🙄😁

[Al_Smith]

I seldom buy anything new but a few years ago I bit the bullet and bought a brand spanking new Stihl weed wacker .It came with a pack of Stihl ultra with the purchase with a recommended ratio of 50 to 1 which extended the warranty .So I ran it with the oil--at 32 to 1 ratio .Funny at that ratio the brand new Stihl plus 40 year old McCullochs  ran equally as well using that stuff at that ratio .They didn't smoke like they were burning soft coal either .--I luv the oil wars  8)

[HolmenTree]

Actually on the back of the Stihl Ultra bottle they recommend 32:1. 40:1  50:1

[Southside]

I run my 372's at 32:1  - always have, always will.  For the past 5 years or better I have been using the gallon size 2 cycle marine injection oil that Wally World carries, it's blue and it's cheap, mix that with regular gas from the pump, E10 at most.  The way I see it if that stuff was good enough for my 671 cc Rotax powered muscle sled then it sure is good enough for a 72cc saw, and I have never damaged one doing it this way.       

[Al_Smith]

 :D They just carry on like a chainsaw is a vintage Roll-Royce or something .Run aviation gas,high octane rocket fuel ,oil at 100 to 1 ratios and so much stuff you could over load this server .Of course as is my nature my job is to heckle which I'm very good at .Truth be known I could care less what anybody does with their saws . 8)

[martyinmi]

All octane does is prevent the spontaneous ignition of the fuel-air mixture as it is compressed.

Spontaneous ignition...or auto ignition?  ;D

[John Mc]

All octane does is prevent the spontaneous ignition of the fuel-air mixture as it is compressed.

Spontaneous ignition...or auto ignition?  ;D

Took those words from a page explaining about Octane. They went further to explain that it would ignite from the compression alone, rather than needing a spark. (Now that you mention it, igniting from compression is not really "spontaneous")

[JohnW]

John Mc, ignition from compression is still spontaneous combustion, according to the usual meaning of spontaneous combustion.  It's combustion, not according to the plan, or maybe combustion on its own timing, not by the spark plug.

[John Mc]

John Mc, ignition from compression is still spontaneous combustion, according to the usual meaning of spontaneous combustion.  It's combustion, not according to the plan, or maybe combustion on its own timing, not by the spark plug.

I'm aware that the term is normally used that way. My comment was more an observation that it is an odd use of the word. It is not really "spontaneous" by the common (non-automotive/gas engine) use of the word. You compressed the mixture, it caused the mix to heat up and ignite. Nothing really "spontaneous" about that, even though it is not the intended method of ignition.

[HolmenTree]

My experiences in timbersports I've had "run away " saws.
Once had a Stihl 090 that I modified with high compression running a race fuel mixture.
After the last cut when I tried to shut it off it just kept going WOT. Pulled the spark plug boot off the plug it still kept screaming.
Ended up holding the throttle wide open until it cooled down enough to stop.
Red hot piece of carbon or something kept it going

[sablatnic]

Same happened to me with a heavily modified Partner.
It just idled along with ignition turned off,  while I had time to unscrew the top cover and pull the wire off the plug. Kept idling without the wire for several minutes, till it had cooled off.
At the time we guessed that the spark plug or a piece of carbon kept warm enough to keep it running.

[Al_Smith]

All octane does is prevent the spontaneous ignition of the fuel-air mixture as it is compressed.

Spontaneous ignition...or auto ignition?  ;D

Oh goody Marty showed up . 8)

[Al_Smith]

It wasn't a chainsaw but I once owned a 1973 Olds Toronado that would diesel enough you could drive it a city block before it would stop .455 cubic inch monster that loved gasoline .It was supposed to have a solenoid on the carb throttle plate to shut it completely off to prevent that .Evidently it didn't work so well .Got real stinky dieseling on gasoline,phew .
Now that engine was in the days of"low lead" not no lead .So perhaps the formulation of that stuff wasn't so good .It ran pretty good on Sunoco 260 though .

[thedoublejranch]

I just run what the manufacturer of the engine recommends. Works for me but I've only been using a chainsaw for the last 42 years so maybe I'm being foolish.

42 years ago, be hard pressed to find gas with alcohol in it, now its almost a normal thing. You have to actively search for alcohol free fuel now and the sources are very limited. That fuel creates havoc if you have saws that set with no use for a few months or more. If your saws run all year long, its a non issue as you stated.
To find alcohol free pump gas, try http://pure-gas.org

[Enderslbz]

I've heared of scented fuel additives for the RC cars that run on the nitro methane stuff, never for a chainsaw though  ???

Never tried an octane booster in the 2 strokes. I may try it in one of my older saws and see what it does.

OMG I love that smell, why would you ever want to cover it up  ???

[JohnW]

I have a couple octane questions, if I can borrow the post for a minute.  I suppose if the octane is too low, and you have run on when you turn your saw off, then the saw is probably also firing too early before top dead center, also, resulting in power loss.  Is that right?  I've been using 100LL in my saws (310, 372, and 395) but as people have pointed out, low lead aint no lead.  I should probably switch.  The 92 octane 50:1 premix stuff looks good.  On switching, I probably need to get my saws retuned, right?