# Gas/oil mixture for Stihl 090



## Bob Rooker (Feb 21, 2014)

I recently purchased a Stihl 090. Somewhere I heard or read that the gas/oil ratio was 20:1. I realize that this was back when oil was not as good as it is today and synthetic was almost unheard of. I have used Amsoil synthetic 2-cycle in all my 2 cycle engines for over 20 years, with no problems, in my 0ll, 017, 041 Farm Boss, 051 and 075. I usually mix it 75:1. What do you guys think about me using that ratio in the 090? I am on my last bottle of Amsoil. Can you recommend another good brand of synthetic 2 cycle oil? What ratio should I use with that brand? Thanks! This site is the best! Bob R.


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## kimosawboy (Feb 22, 2014)

I run synthetic at 50-1 in mine...no problems.
G Vavra


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## blades (Feb 22, 2014)

At the price Amsoil charges might as well buy Stilh's own, 75-1 way to lean stick with 50-1 most older saws of that vintage were 40-1, Stuff from the 50's& 60's generally40 or 32-1, never ran across anything requiring 20-1 ( by this point dang near running a diesel) I have been running generic synthetics they work just as well as the fancy priced items. Course if you like spending money on this might as well get Royal Purple ( that make Amsoil look cheap)


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## Bob Rooker (Feb 22, 2014)

kimosawboy said:


> I run synthetic at 50-1 in mine...no problems.
> G Vavra



Thanks for your answer. Bob R.


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## Bob Rooker (Feb 22, 2014)

blades said:


> At the price Amsoil charges might as well buy Stilh's own, 75-1 way to lean stick with 50-1 most older saws of that vintage were 40-1, Stuff from the 50's& 60's generally40 or 32-1, never ran across anything requiring 20-1 ( by this point dang near running a diesel) I have been running generic synthetics they work just as well as the fancy priced items. Course if you like spending money on this might as well get Royal Purple ( that make Amsoil look cheap)



According to page 5 in my Stihl 075 Service Manual, the recommended mix is 25:1 for "other branded" two-cycle oils and 40:1 with STIHL two-cycle engine oil. I knew I had seen or heard about mixing 20:1 (25 is close enough to 20 for me)! I think your recommendation of 50:1, using synthetic oil, is probably right on. G Vavra agrees so that makes it unanimous. The generic 2-cycle oil is probably made by the same company that makes it for Stihl: Shell, Valvoline, etc.! However, The Poulan Weed Eater Synthetic 2-stroke oil I bought at Wal-mart recommends a mix of 40:1. What does the generic brand you use recommend? What is the brand? Thanks. Bob R.


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## Bob Rooker (Feb 22, 2014)

Bob Rooker said:


> Thanks for your answer. Bob R.



Forgot to ask - what brand 2-cycle synthetic oil do you use? Thanks, again. Bob R.


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## blades (Feb 22, 2014)

what ever house brand or on sale brand is available at where ever i might stop. Even running , at 40-1, old outboard oil at present . I do not make a habit of this but was given 4 or 5 quarts worth so besides the snowblower some ends up in the saws as well. My 7900 that developed a base gasket leak showed no signs of ill will. That particular one is around 10 years old now and a lot of cutting under its bonnet.


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## steve easy (Feb 22, 2014)

I run 20:1 in all my saws ,090's down to my top handle 019. I use stihl,husky,amex oil , keep a few plugs on hand when they get to fouled up i replace them. Sure you use a bit more oil and a few plugs here and there but its cheaper than rebuilds.


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## Bob Rooker (Feb 22, 2014)

blades said:


> what ever house brand or on sale brand is available at where ever i might stop. Even running , at 40-1, old outboard oil at present . I do not make a habit of this but was given 4 or 5 quarts worth so besides the snowblower some ends up in the saws as well. My 7900 that developed a base gasket leak showed no signs of ill will. That particular one is around 10 years old now and a lot of cutting under its bonnet.



Blades, I would be careful using outboard motor oil in my chainsaw. Outboards run a lot cooler than a chainsaw and outboard oil will not hold up under the high temperature of a chainsaw. That is what I remember hearing or reading somewhere. lol! Bob R.


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## KenJax Tree (Feb 22, 2014)

blades said:


> At the price Amsoil charges might as well buy Stilh's own



Not sure how you figure this.

A 6 pack of 2.6oz bottle of Utlra is 15.6 oz. @$15.00 and its only FC rated.

A quart of Amsoil Saber is 32 oz. @$10.00 and its FD rated

Give me Amsoil.


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## Bob Rooker (Feb 22, 2014)

KenJax Tree said:


> Not sure how you figure this.
> 
> A 6 pack of 2.6oz bottle of Utlra is 15.6 oz. @$15.00 and its only FC rated.
> 
> ...



KenJax Tree, I have used Amsoil oil in all my stuff for over 20 years and have had excellent results. My Stihl 011 I bought in 1989, and use a lot, still starts and runs like new! Comparable results with the rest of my saws and vehicles. Amsoil is way over-priced (unless you compare it to Ultra) and they are arrogant so I have switched to other synthetic oil for my vehicles. When I run out of Amsoil 2-cycle I will try another brand as soon as I figure out what the FC and FD ratings are. I'm sure the technology is out there for other oil manufacturers to make as good a product as Amsoil, for less money. It would be nice to hear from someone who has found this 2-cycle oil so I don't have to do so much research. Bob R.


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## KenJax Tree (Feb 22, 2014)

When you start looking at high end synthetic ester or castor oil Amsoil is cheap compared to Motul,Klotz,Bel-Ray,Maxima,etc. I use these oils and they're some of the best out there but they're pricey


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## Bob Rooker (Feb 22, 2014)

rogue60 said:


> Your getting up there with an 090 as its a big bore as such and needs some oil.... Personally id go with 32:1 and not get hung up on the it must be synthetic oil or she will blow crap lol...A good mineral oil say like from castrol will be fine, seems they ran just fine on mineral oil for like 30+years? go figure? lol......



Rogue60, I hear you about it throwing craps if you use the wrong ratio. Back in the late 70's I had a McCullough 2-10 chain saw that called for 20:1 mix and I used some 2-cycle oil that said 40:1 mix and mixed it accordingly. Results? The 2-10 "died" and I had to put a new piston and rod assembly in it. Luckily the cylinder was chrome plated and it was okay but the piston was burned-up! This is why I am trying to make sure I use the right ratio in this Stihl 090! Thanks. Bob R.


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## Bob Rooker (Feb 22, 2014)

KenJax Tree said:


> When you start looking at high end synthetic ester or castor oil Amsoil is cheap compared to Motul,Klotz,Bel-Ray,Maxima,etc. I use these oils and they're some of the best out there but they're pricey
> 
> 
> Sent from my iPhone using Tapatalk



KenJax Tree, I know nothing is cheap but I wish things were just "reasonable" like they once were before big oil started making billions of dollars in profits - every quarter! I have never heard of the oils you mentioned and am guessing they are common to your area. Here in the mid-west they are not available. I may continue to use Amsoil after I get through checking out other synthetic brands. Thanks. Bob R.


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## KenJax Tree (Feb 22, 2014)

They're probably the most common oils used by members here on AS and any motorcycle shop will have or can order them.


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## Bob Rooker (Feb 22, 2014)

kimosawboy said:


> I run synthetic at 50-1 in mine...no problems.
> G Vavra



G Vavra, What kind (brand) synthetic oil have you been using and how long have you been using it in your 090?


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## Bob Rooker (Feb 22, 2014)

KenJax Tree said:


> They're probably the most common oils used by members here on AS and any motorcycle shop will have or can order them.
> 
> 
> Sent from my iPhone using Tapatalk



How about that?! Let's hear it from all those guys on AS who are using Motul, Klotz, Bel-Ray and Maxima oils! Are you satisfied with the results? Where do you purchase the oil? Thanks! Bob R.


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## Bob Rooker (Feb 22, 2014)

Bob Rooker said:


> How about that?! Let's hear it from all those guys on AS, who live in the mid-west, who are using Motul, Klotz, Bel-Ray and Maxima oils! Are you satisfied with the results? Where do you purchase the oil? What mix ratio would you suggest for my Stihl 090? I live in the Kansas City area and would like something close to there. I guess I will look up these brands on the internet and see if I can find something. Thanks! Bob R.


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## KenJax Tree (Feb 22, 2014)

Post it in the chain saw forum


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## Knobby57 (Feb 22, 2014)

Bell-ray and royal purple both fantastic oils . I've been using royal purple for 5 years and bell-ray before that . Run all my saws at 40-1 and non ethanol fuel . Just be sure your mixture is properly adjusted or your type of oil won't make much difference . Motul always smells noxious to me my buddy runs that stuff he has never had a saw go down yet and cuts 75-100 cord of firewood a year with a 025 and a 046 .over 10 years now and has only ever changed spark plugs and filters 


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## Bob Rooker (Feb 22, 2014)

KenJax Tree said:


> Post it in the chain saw forum!
> 
> I thought I just did! I can't find anything on the internet for any of these brands, in my area, so I will stick with Amsoil Sabre. Thanks. Bob R.


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## Bob Rooker (Feb 22, 2014)

Knobby57 said:


> Bell-ray and royal purple both fantastic oils . I've been using royal purple for 5 years and bell-ray before that . Run all my saws at 40-1 and non ethanol fuel . Just be sure your mixture is properly adjusted or your type of oil won't make much difference . Motul always smells noxious to me my buddy runs that stuff he has never had a saw go down yet and cuts 75-100 cord of firewood a year with a 025 and a 046 .over 10 years now and has only ever changed spark plugs and filters
> 
> 
> Sent from my iPhone using Tapatalk



That says a lot for the oils! These are obviously somewhat common in your area but not in mine. Of course I could always order them on the internet after I find a source. Thanks! Bob R.


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