The 50:1 2 Cycle Oil Myth ? "epa"

[RaisedByWolves]

I still have some of this out in the barn. Don't have the heart to toss it:

HELLO!


Antique saws should allways run Antique oil, rember pull tops?

This is all I run in my old saws and I mix it at a healthy 8:1 ratio.

Smokes a little, but it gets er done.


.

 

[thomas72]

I do not believe that is a Honda built CR500r. Looks like they are building the motor and putting it in a cr250 frame.

 

[2000ssm6]

I do not believe that is a Honda built CR500r. Looks like they are building the motor and putting it in a cr250 frame.

Nope, not a all original 500 but close enough. For $9000, I'll buy a car/truck anyway.

 

[Timber_Hitch]

Carbon ?

Well that sounds good, but the more oil you burn, the more carbon it produces, which reduces the life of your engine. This piston failure guide can show the results of carbon scoring.

Carbon, one of the softest materials known is a primary lubricant. "Fact"

 

[Poley4]

Carbon, one of the softest materials known is a primary lubricant. "Fact"

True, when it is the form of graphite, but that is not the form of carbon found inside an engine. Carbon comes in many hardnesses ranging from graphite on one end all the way to diamonds on the other. Carbon found inside an engine is definitely hard enough to score an aluminum piston.

 

[Timber_Hitch]

Weird Science

True, when it is the form of graphite, but that is not the form of carbon found inside an engine. Carbon comes in many hardnesses ranging from graphite on one end all the way to diamonds on the other. Carbon found inside an engine is definitely hard enough to score an aluminum piston.

The new synthetic oils claim by using them there will be no carbon build up, but those that work on 2 cycles know this is a stretch. Here is the Science behind the carbon build up. The design of the cylinder mass needs to produce an I.D. that will match the Piston's O.D. at operating temperature. This being said the C.T.E. needs to be calculated very precisely out to ".0000" 4 decimal places. The Aluminum expansion is greater than the Nickel Chromium Alloy plating that creates a problem for the engineering. To overcome this Stihl has tested and found the best case scenario for the plating thickness. In short, when the 2 cycle engine is at operating temperature any mismatch between the cylinder and the piston will back fill with carbon. The problem area with C.T.E. has always been in the exhaust area and many configurations have been tried through the years. I have found that aftermarket cylinders and pistons are slightly different than O.E.M. when measured.


I only recently remembered everything I learned at MIT since I fell on my head with full climbing gear topping a Bamboo !

 

[PES+]

Holy Cow Another one

Ummmmm What the heck are talking about?

Nikasil has no chrome and the process has been around for almost thirty years.

Mahle did all the research on the optimal coating thickness for all the various applications.

The thinness of the finished plating as well as it's structure make it follow the expansion of the jug near perfectly

The main damage that is very likely to happen by the use of too much oil is caused by carbon build up in the ring grooves which inhibits the heat transfer from the piston to the cylinder.

Once the piston overheats it cooks more of the extra lubricant onto the piston which then leads to detonation and seizure.

(most often the piston crown over the exhaust port)


ANY build up on a piston crown has the potential to be disastrous under various operating conditions.

I am sure Stihl did do some testing on this as their dino oil was notorious for leaving quite a lot of deposits in the engine ESPECIALLY when mixed in concentrations higher than 50 to 1 and they did in the past run looser piston to cylinder tolerances to deal with it. (I have not measured any of them lately but will when I think of it)

Which aftermarket pieces have you measured and what did you find?

 

[Timber_Hitch]

Ummmmm What the heck are talking about?

Nikasil has no chrome and the process has been around for almost thirty years.

Mahle did all the research on the optimal coating thickness for all the various applications.

The thinness of the finished plating as well as it's structure make it follow the expansion of the jug near perfectly

The main damage that is very likely to happen by the use of too much oil is caused by carbon build up in the ring grooves which inhibits the heat transfer from the piston to the cylinder.

Once the piston overheats it cooks more of the extra lubricant onto the piston which then leads to detonation and seizure.

(most often the piston crown over the exhaust port)


ANY build up on a piston crown has the potential to be disastrous under various operating conditions.

I am sure Stihl did do some testing on this as their dino oil was notorious for leaving quite a lot of deposits in the engine ESPECIALLY when mixed in concentrations higher than 50 to 1 and they did in the past run looser piston to cylinder tolerances to deal with it. (I have not measured any of them lately but will when I think of it)

Which aftermarket pieces have you measured and what did you find?

Hmmmm, did I mention Nikasil ? answer = no
does Stihl Manufacturing mention Nikasil answer = no

I wish people would stop putting words in my mouth and start putting Lobster and Shrimp , I am tired of eating peanut butter an fluff. See even on this site you have your Fluffernutters !

 

[PES+]

Hmmmm, did I mention Nikasil ? answer = no
does Stihl Manufacturing mention Nikasil answer = no

I wish people would stop putting words in my mouth and start putting Lobster and Shrimp , I am tired of eating peanut butter an fluff. See even on this site you have your Fluffernutters !

So what you are saying is Stihl went back to chrome plating?

this is getting good

 

[Lakeside53]

Pest smells fresh meat:greenchainsaw:

 

[ciscoguy01]

Ummmmm

Soooooo, should we or should we not use 50:1??? That's really the only question I'm wondering...

opcorn:

 

[Pissfirwillie]

So what you are saying is Stihl went back to chrome plating?

this is getting good

A little off the subject, but worth mentioning. A fella on our crew recently replaced his 441 cylinder, and I believe he said it was made by someone else other than Mahle. I think he said it was an Italian cylinder. I this a recent change. All my 046's have Mahle cylinders so far.

 

[16gauge]

Experts

Hmmmm, did I mention Nikasil ? answer = no
does Stihl Manufacturing mention Nikasil answer = no

I wish people would stop putting words in my mouth and start putting Lobster and Shrimp , I am tired of eating peanut butter an fluff. See even on this site you have your Fluffernutters !

Now here we have another expert with all the right answers for the others. This is when I get sceptical. Personal experience over time usually turns out to have a solid basis. High quality 40:1 mix in chainsaws has worked for me over many years...actually 42:1 is what it turns out to be. For saws I have that were made in 60s, 70s, 80s, 90s, 00s. Good gas with premium oil. Never had a carboned up siezed ring from too much oil...and never had a saw quit unless it was a failed ignition or air leak. Nikasil is ok, as is a chrome plated or plain aluminum bore. Just take care of the saw and it will work fine until it just plain wears out. Yes...any saw will eventually wear out. Just like old dogs do...still throw them the chicken bone anyway even if the "EXPERTS" say NO.

 

[Lakeside53]

A little off the subject, but worth mentioning. A fella on our crew recently replaced his 441 cylinder, and I believe he said it was made by someone else other than Mahle. I think he said it was an Italian cylinder. I this a recent change. All my 046's have Mahle cylinders so far.

Stihl has been using a Spanish factory for some time. They also make cylinders in Brazil.

 

[tree md]

I'm kind of confused after reading some of the different opinions on this thread.

I was told by my dealer to run 50:1 in my new 441, 192T and 200T which concerned me a little. I have never run saws that lean. He explained some mumbo jumbo about the newer saws being designed to run 50:1. I have always run my older stihls 40:1. My partner runs all of his stihls 32:1. Which mix will provide the longest life? It would be nice if me and my partner could compromise and run the same mix (40:1) and cut down on some of the confusion about which saw gets which mix when it comes to my crew.

 

[GASoline71]

Soooooo, should we or should we not use 50:1??? That's really the only question I'm wondering...

opcorn:

If you're serious... yes... with the modern 2 stroke oils... it will be fine.

Gary

 

[Lakeside53]

If we'd had the web back in '70.. want to bet the argument would be "32:1 NO WAY... I'm sticking with 16:1", but I run my saws at 10:1 when there's a bunch of mosquitoes around. Haven't seen any bigfoot (except for Gary) lately either? :greenchainsaw:

 

[Pissfirwillie]

Stihl has been using a Spanish factory for some time. They also make cylinders in Brazil.

Is the Spanish place a Mahle factory, or someone else. I assume the cylinder was nikasil coated anyhow.

 

[Lakeside53]

It's not a Mahle factory. Stihl has rarely admitted using Nikersil - they refer to "specially coated/impregnated bores" etc. if you see a cylinder with a tiny "cr" on it, it's not going to caled "nikersil" (trademark of Mahle).

 

[ciscoguy01]

But

If you're serious... yes... with the modern 2 stroke oils... it will be fine.

Gary

I usually run like 45:1. Will a little more oil than the 50:1, say 45 or 40:1 be ok to run in the newer saws??? In your opinion, and everyone elses, what mix gives the longest saw life???

Thanks eh?
Dude