Fuel Mixture Best 2 stroke oil?

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Vikingimike01

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Hey guys! I am wondering what is the best type of oil for these 66cc chinese 2 strokes.

So: I live in a continental climate zone, and the temperature is usually 25 degrees celsius (77 fahrenheit) , in the summer it's about 40 (104 fahrenheit).
I'll probably use a 30:1 or 25:1 oil ratio since I want my engine to last. I'm wondering what's the best oil to make the engine last a long time? I could use 10W30- 10W40, or anything. Thanks in advance!
 
I'm wondering what's the best oil to make the engine last a long time? I could use 10W30- 10W40, or anything. Thanks in advance!
Believe it or not there is oil made specifically for air cooled 2 strokes so why mention
10W30- 10W40 oil?
They were probably using 30 weight oil in China in these motors when they were legal
and being used because of the cost and unavailability of 2 stroke oil. Maybe even used oil.

Asking for oil brand recommendations is like asking which religion is the true one.

https://en.wikipedia.org/wiki/Two-stroke_oil
Comparing regular lubricating oil with two-stroke oil, the relevant difference is that two-stroke oil must have a much lower ash content. This is required to minimize deposits that tend to form if ash is present in the oil which is burned in the engine's combustion chamber. Additionally a non-2T-specific oil can turn to gum in a matter of days if mixed with gasoline and not immediately consumed. Another important factor is that 4-stroke engines have a different requirement for 'stickiness' than 2-strokes do.
 
No, I'm not trolling..... If I was I'd ask if I can put water in fuel to make the engine run faster.... I heard that from someone....

But thanks, so no. I did read it quickly. They still say you can use it tho. Wich I won't do.
 
I like Pennzoil marine 2stroke oil. its expensive about 7 dollars a quart. but when you consider you can get 4 gallons of fuel mixed with 1 quart at 25 to 1 that's 1 dollar per 50 miles on my bike. I have a 50cc which has been using this oil In its fuel mix for over 2000 miles and runs strong without any issues ever and I run my bikes hard. * I also add 2 capfuls of marvel mystery oil in every gallon( marine 2 stroke oil doesn't have detergents so the marvel oil adds them). I use 200ml of Pennzoil marine per gallon
some people are probably going to argue that marine oil ( which is a thicker oil )is not good for a regular 2 stroke which in a lot of cases is correct. as well it is detergent free. I argue this because our bike motors are not high revving engines and are not the same as a weedwhacker or still saw revving at 14,000 rpm. we rev at 7,000 rpm. thick oil is good for our motors I believe because the are not tight motors and thick oil creates a good ring seal for compression and prevents piston scuffing. I certainly could be wrong because I am not a mechanic but it makes sense and my motors last well which is the litmus test
 
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Note that for break-in, most agree that you should be using a non-synthetic. I run cheapo-depot store brand non-syn for break-in before switching to a good synthetic and fine tuning the jetting.

Some people say a synthetic does not allow the engine to break-in properly, which makes sense.
 
Some people say a synthetic does not allow the engine to break-in properly, which makes sense.
That is an old wives tale.

Break in Oils
Some people claim that you can't break in an engine with synthetic oil,or castor oil. Nonsense. I can seat the rings on a KT100 running Amsoil Saber at 16:1 in a couple of laps. Run what ever oil brand & ratio you plan to use in an engine from the very first start.

Fuel mixture is much more important. Run a little rich at first. Re-jet, use partial choke - whatever it takes to avoid running too lean on a fresh engine. This will reduce cylinder temperatures while helping to wash away the metal particles produced by ring seating.

There is a popular 2 stroke import engine out there with all sorts of break in recommendations. Extra oil, etc. The factory oil advise about 16:1 initially is ok, as long as you add fuel too. That engine is a low quality, inexpensive unit. I have measured cylinders at .005 or more out of round. Piston rings that only make contact at a few spots initially. No wonder they tell you 16:1 - the extra oil helps seal the rings! Running this engine at WOT with enough oil & fuel is the best way to seat the rings - and it will still take awhile...

About 2 Stroke Engine Break-in

I have had may responses to this page asking about breaking in a 2 stroke engine.

Any engine with piston rings takes a little time to fully seat the rings. Once the compression rings are making full contact with the bore, a 2 stroke is good to go. Most professional engine builders agree that short runs at full throttle are the best way to seat the rings. Cylinder pressure forces the rings in to contact with the bore. Higher cylinder pressures happen when the engine is working harder.

Why "break -in" at all?
Good question. Stihl, Husqvarna, Poulan, Ryobi & Homelite make millions of units each year. None of them come with highly detailed instructions to break them in gently, or use more oil. A new chainsaw comes out of the box, and goes right to work at 10,000 RPM & full load on the cutting chain. A 2 stroke race bike rolls off the trailer with a fresh top end - and goes WOT across the desert through the gears.

There are some things to avoid with a mixed fuel 2 stroke engine:

Excessive idling. Little to no cylinder pressure, and reduced fuel / oil flow per revolution. On a motorcycle, you also lose cooling air flow.

Engine braking. Pull that clutch in on long downhill runs. High crankshaft speeds with the throttle closed starves the engine for oil. Engine braking with a 2 stroke is best done with a compression release, and the throttle wide open.
 
A few words about lubrication in 2 stroke motors.

There is a lot of misconception about 2 strolke oils & lubrication of the engine. Let's start by describing how the engine is lubricated.

First, a suitable oil is mixed with the fuel. This oil must dilute completely within the fuel. It does not change, the properties of the oil remain the same. We will cover fuel / lubricant miscibility a little later.

Now, when fuel is dispersed in to the intake air stream by the carburetor, it carries oil with it. Oil however does not vaporize as the fuel does when it enters the crankcase. When the fuel vaporizes, the oil drops out as tiny droplets. This oil ends up on all of the parts inside the crankcase. A thin film of oil is established on the inside of the crankcase.

The oil film on the crankcase migrates in the direction of airflow as long as the engine is running. This means that the oil eventually works it's way through the intake ports, and in to the combustion chamber. When the engine fires, the oil DOES NOT BURN. Spark ignition engines do not generate enough compression to burn high quality lubricating oil. When the engine fires, the oil continues on it's journey - right out the exhaust port. If the oil is of acceptable quality it will still be oil as it leaves the engine. This is the oil you find in the exhaust system.

So why is the oil black? It is contaminated with carbon from the fuel burned, just like the oil in a 4 stroke crankcase. A properly lubricated 2 stroke will have some oil all the way to the tailpipe. It has not burned, but passed clear through the engine doing it's job.

Now let's talk about fuel & oil types. We say "fuel" because what you get from a pump at the local station only resembles gasoline. Most areas have 10% Ethanol added to the mix, as well as detergents and other things. Then there is E85, which is 85% Ethanol. There are other blends out there too.

Oil. A huge can of worms. Everyone seems to have an oil story. Here are the basics. There are a few types of 2 stroke oil described by specification:

TC-W3 This specification is for water cooled 2 stroke engines. It is an API / NMMA specification

JASO FD This specification is often described as a standard for air cooled 2 stroke engines. It is a Japanese Automobile Standards Organization specification.

ISO-L-EGD This is the European specification, which is based on JASO

Racing oil A wide range of manufacturer described specifications & tests.

In a general sense, the TC-W series oils tend to be lower viscosity, and contain some solvent. Many times the container has little pictures of Chainsaws, Outboards, Snowmobiles etc. Some people would be quick to point out that the spec is not JASO, and that some equipment requires JASO oil for warranty. To be fair, JASO standards did not even exist before 1994, and many of those engines were designed in the 1950's.

The requirement for JASO / ISO oils is common on imported air cooled engine warranties. Much of that reflects emissions requirements, as the engines must only run as little as 50 hours while complying with the standards. They run very lean, and with limited oil to satisfy the requirement. JASO / ISO spec oils are fine oil, but the specifications were not written for engine life - just for emissions standards.

Miscibility. Not all oil will mix with all fuels. Things that mix with petroleum (Gasoline), may not mix with alcohols (Ethanol,Methanol). This can lead to issues with something called phase separation. This means that the alcohol can separate from the gasoline, and mix with any water present in the fuel. If the oil does not mix with both fuel components, bad things can happen. For instance both Ryobi & Homelite brand oils meet JASO-FD / ISO-L-EGD standards, but are marked with a bold faced warning telling you not to mix them with E85 fuel.


So, what oil? What mix?

Use any oil that meets the engine manufacturers specification. Use the mix ratio specified by the manufacturer. The engine company knows what oil ratio they designed it for. A finely finished tight tolerance engine may be fine with 50:1 Other manufacturers specify 32:1 Additional oil is not a big issue in a 2 stroke. Running 24:1 in an engine that can run 32:1 will not hurt it - but running 50:1 may damage it. The company that claims you can run their secret sauce oil @ 100:1 in any engine does not replace engines when they fail. Believe in the engine manufacturers recommendation.

Racing engines with high BMEP need more oil. Air cooled Snowmobiles & Ultra Light Aircraft typically run 32:1, and sometimes 20:1 Racing Go-Kart engines run as much as 16:1 If additional oil reduced horsepower, the Kart racers would be doing something different.

Which brings us to the next point - Power. Running more oil does not reduce horsepower. As long as you change jets or adjust the fuel mixture for the proper quantity of fuel in the engine, the oil is just along for the ride. When I ran alcohol in desert race bikes, I kept the
fuel mix at 32:1 - which gave me almost twice as much oil per revolution as It has on gasoline. Never had a problem with that even on long races like Barstow to Vegas.

We prefer Castor Oil for running hard, especially with air cooled engines in the desert. Castor oil is unique, because it will mix with both alcohol and gasoline. This has obvious advantages with the blended fuels now at the pump. If the average JASO oil can't be mixed with E85 - how well does it really mix with E10? Castor covers the whole range of fuel, and still has the highest flash point of all of the 2 stroke oils.

If you run at more moderate performance levels, cooler climates, etc. the TC-W3 oils are ok - as long as you run them at a high enough ratio. TC-W3 has a solvent in it to thin it down, so step up one ratio. For example, if your engine calls for 32:1, move to 24:1 & re-jet your fuel mixture. Pay attention to the possibility of phase separation with the Ethanol in the fuel, and agitate any gas can before you pour out of the container.
 
nice explanation . can one run castor oil after running the others i may make the switch
 
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