Oil mix ratio for Yamaha Zuma 50 2 stroke?

[alex45223]

Hey, my oil to fuel line doesn't seem to work anymore. 

I have to premix my own fuel. 

How many fluid ounces of oil do I mix per every 1 gallon? 

[Lucass2T]

1 part oil to 50 parts of fuel.
100ml oil to 5 liters of fuel.

[alex45223]

I'm horrible at math. What is that for 1 gallon?

Google says 5 liters is 1.3 gallons.
So 100 ml is 3.381413 Fluid OZ for 1.3 gallons.

If my math is correct. That means you do 3 fl OZ for every 1 gallon? I guess that should be good enough?
Is it better to overestimate I assume? SO put maybe a little more than 3 oz in per gallon?

[Zino]

128 oz in a gallon so you would be less than 3 oz oil closer to 2.6 ounces

I would not go much lower than 40 to 1 (so 3 ounces would be on the max I would use per gallon )
A hair over 2.5 is the way I would do it

Too much oil actually leans out your 2 stroke and cause you to seize

The stock pumps meter out at the 50 to 1 range with good oil

[Lucass2T]

On any well tuned (mixture that is) street setup a 2% oil mixture (50:1 mix) with a modern quality oil will work perfect.
If you feel your tuning skills are supreme you can lean it out even more. Aprilia Di-tech engines run at 70:1.

Don't worry too much about mixing microscopically correct. Rather spend you money 9n a good quality oil and make sure the carburetor is tuned correctly.

[snaker]

A lot of the oil containers have some version of ratio measurements engraved on the container.
I have actually hung onto a easy to read container and made it a measure cup for other oil brands.
I like the ones where you squeeze the oil into another section of the container that has measure marks.

You can buy ratio measurement pour cups with the ratios included as well.
Sounds like you're up on the standard/metric differences, so that's a help

Side note: I've bought some 2 stroke chainsaws and other stuff over the years.
Always amazed that the owner's manuals will say something like: 'Use our brand oil at 50:1 but any other brand oil use at 30:1
So even if, let's say, Stihl and Husqvarna run their own oils at 50:1 you're to use those same oils at 30:1 in the other brand's equipment.

[aeroxbud]

Jun 29, 2024 9:03:42 GMT -5 snaker said:

Side note: I've bought some 2 stroke chainsaws and other stuff over the years.
Always amazed that the owner's manuals will say something like: 'Use our brand oil at 50:1 but any other brand oil use at 30:1
So even if, let's say, Stihl and Husqvarna run their own oils at 50:1 you're to use those same oils at 30:1 in the other brand's equipment.

It's a Yamaha. You must only use Yamalube.


On a more serious note. I would go to a slightly larger main jet as it will run leaner adding oil the the fuel.

[Lucass2T]

Jun 29, 2024 9:31:53 GMT -5 aeroxbud said:

Jun 29, 2024 9:03:42 GMT -5 snaker said:

Side note: I've bought some 2 stroke chainsaws and other stuff over the years.
Always amazed that the owner's manuals will say something like: 'Use our brand oil at 50:1 but any other brand oil use at 30:1
So even if, let's say, Stihl and Husqvarna run their own oils at 50:1 you're to use those same oils at 30:1 in the other brand's equipment.

It's a Yamaha. You must only use Yamalube.

Come on man don't say that🙈

[mopedmofun]

I have a different take. I might not have as much experience as the heavy hitters who posted previously, but I’m a logical thinker.

In my opinion, the 50-1 benchmark is largely based on emissions, not the ideal amount of oil the scoot wants. I run my pump bikes with 1oz in tank, and my mix bike with 3oz per gallon. I ran it with 4oz for about 6months before I noticed it was smoking heavy.

The idea of a 32-1 mixture leaning my mixture seems far fetched to me. We are talking 32 units gas to 1 unit oil.

A 40-1 mix sounds safe to me.

[mopedmofun]

Jun 29, 2024 9:03:42 GMT -5 snaker said:

Side note: I've bought some 2 stroke chainsaws and other stuff over the years.
Always amazed that the owner's manuals will say something like: 'Use our brand oil at 50:1 but any other brand oil use at 30:1
So even if, let's say, Stihl and Husqvarna run their own oils at 50:1 you're to use those same oils at 30:1 in the other brand's equipment.

This is because some lab coat guy knows their oil is the shit, but anything less needs MORE oil to cool the same amount. Stihl actually extends their warranty considerably if you buy their oil.