661 Oil Test 32:1 vs 40:1 vs 50:1 ?

[KG441c]

390 piston top. Unknown amount of runtime. Carbon is starting to come loose now.

View attachment 434220

So Mike u think the Super is cutting the carbon?

 

[mdavlee]

So Mike u think the Super is cutting the carbon?

Could have been the VP fuel. I don't think super is going to clean it. I've used up all the super so now it's mobil with pump gas.

 

[bwalker]

I still dont think a piston should be carbon free? I dont get where folks think an oil should burn without a buildup / byproduct? I still think any of it will buildup if the saw is tuned properly. This is 800t through my 461 with about 8 gallonsView attachment 434265

A piston should have carbon on it. A four stroke motors pistons have carbon on them. No carbon means your too rich.

 

[bwalker]

I personally don't care for R50 because of it's limitations in the cold (but I'll still test it...never know!). Per klotz it's good down to about -15ish. While 800 is good down to -54...guys up in Canada run 800 a lot. (per Motul...no reason to doubt this claim though)

Not that I would cut wood in anything under say -20 that is about my own personal limitation lol But the above info certainly leads me to believe that r50 would be less of a performer in even the mild cold.


My concern with K2 is the PIB in it, being a health hazard. Why breathe the stuff, if 800 does the same thing and doesn't have PIB in it.

What health Hazzard are you referring to?
Breathing exhaust is a bad thing and the oil is the least of your worries.

 

[bwalker]

Things have moved along somewhat since ww2, just like oil ratios. LOL
Thansk

Don't tell the Europeans that..

 

[Rx7man]

A piston should have carbon on it. A four stroke motors pistons have carbon on them. No carbon means your too rich.

or too hot or too lean!

 

[bwalker]

or too hot or too lean!

Typical a two stroke piston that's run lean will have lots of deposits. Unless it's gotten hot enough to start melting the crown away and then it will appear sand blasted.

 

[Trx250r180]

Why would my 70cc saw with a 32 inch bar feel like it makes more power tuned rich ?

 

[bwalker]

Why would my 70cc saw with a 32 inch bar feel like it makes more power tuned rich ?

Two strokes typically make more torque under heavy load when ran a bit rich. It's for this reason that bike carbs have power jet carbs that dump a little more fuel in from half to full throttle.

 

[bwalker]

Two strokes typically make more torque under heavy load when ran a bit rich. It's for this reason that bike carbs have power jet carbs that dump a little more fuel in from half to full throttle.

However, if your piston is silver your more than a little rich.

 

[Trx250r180]

Thanks sir ,i also noticed if lean the low side a bit ,the throttle response is real quick ,but harder to start ,works nice when limbing though with a bigger saw ,my plugs are pretty clean still ,and looking down the exhaust port piston top is dry ,but not clean /washed ,i need to recheck after yamalube now ,before try the mobil oil ,the dumonde has been the cleanest and best throttle response i have found so far ,but the price is also the highest of them all .

 

[Rx7man]

Two strokes typically make more torque under heavy load when ran a bit rich. It's for this reason that bike carbs have power jet carbs that dump a little more fuel in from half to full throttle.

This is true of all engines.. Holley carbs had power valves that dumped more fuel in under heavy load as well.. I think peak torque occurs around 12.5:1 Air/Fuel ratio, Stoichiometric is 14.7:1, and best economy is around 15.5:1 IIRC... a lot of forced induction engines run richer than 12.5:1 for the additional cooling of the extra fuel, you don't lose very much power going down into the 11's, but you certainly save your engine.

 

[nitehawk55]

Is Redbull trying the Motul 800 T2 off road or the 800 T2 road racing ? According to what I have read the off road is for up to 250cc and the road racing for over 250cc .

 

[redbull660]

dumonde, mobil 1, 800 off road, R50, H1R , Saber , K2 , 2R , & Ultra

 

[porsche965]

I wonder if the bookies in Vegas would run line on these 9?

 

[bwalker]

I would really like to see this test run with a carb equip saw tuned to a setpoint.

 

[bwalker]

We don't have a clue what the real issue is there. I suspect a combination of a few things, not just the fact H1R has different combustion properties.

We simply cannot form any real conclusion from theses comparisons. Other than demonstrating they all provide adequate lubrication, we have learned little to nothing IMHO.

I still appreciate the effort, and find it intriguing, nonetheless.

I have seen enough anecdotal evidence across multiple applications to suggest that H1R does indeed inhibit combustion. The Ultra light test pointed in this direction as well.
Even if it didn't do this I still wouldn't run the stuff as its simply not that great.

 

[KG441c]

Could have been the VP fuel. I don't think super is going to clean it. I've used up all the super so now it's mobil with pump gas.

Ya Im thinkin quality fuel has alot to do with it too

 

[nitehawk55]

dumonde, mobil 1, 800 off road, R50, H1R , Saber , K2 , 2R , & Ultra

Great , thanks....kind of lost track .
What is the difference between the 2 types of Motul 800 ? I see the road racing maybe has more esters in it and is dyed differently (red vs orange )

I already use Saber at 40:1 so I'm going to try both types of the 800 in both M-tronic/auto-tune and old school saws I have just for the heck of it . Local bike shop carries both .
I may tweak the ratio a bit heading toward 50:1 , I won't run richer than 40:1

 

[redbull660]

I would really like to see this test run with a carb equip saw tuned to a setpoint.

as in a 660 tuned to 2800 idle 13200 top using a fast tach?

someone will complain it's not four stroking correctly or this ratio was too rich or that ratio too lean, or that it should of been tuned in the wood... I'll let the computer do the work. It is unbiased and looking for the same thing all the time.

Great , thanks....kind of lost track .
What is the difference between the 2 types of Motul 800 ? I see the road racing maybe has more esters in it and is dyed differently (red vs orange )

800 off road

https://www.motul.com/ca/en-US/products/oils-lubricants/800-2t-factory-line-off-road--2

https://www.motul.com/system/product_descriptions/technical_data_sheets/77816/original/800_2T_Factory_Line_Off_Road_TDS_(GB).pdf?1388420014

800 road racing

https://www.motul.com/ca/en-US/prod...-road-racing--2?f[engine_type]=22&f[range]=21

https://www.motul.com/system/product_descriptions/technical_data_sheets/77818/original/800_2T_Factory_Line_Road_Racing_TDS_(GB).pdf?1388420312