2T oil in gas tank?

rentonhighlander · Post by **rentonhighlander** » Tue May 07, 2013 11:44 pm

Curious if anyone premixes a little 2T oil in their gas tanks on the 50cc's.

DemRemz · Post by **DemRemz** » Wed May 08, 2013 1:30 am

its good to do when you first get them brand new for the first tank. But you dont want to take the chance of getting an oil lining on your cylinder wall. Wont hurt it, but it will just smoke a lot. But I am not a fan of oil pumps, any scooter I get that has them, I plug them up and premix. I dont trust them that much. Better safe then sorry.

TVB · Post by **TVB** » Wed May 08, 2013 2:36 am

Never have. And with nearly 20K trouble-free miles I'm getting 80-90mpg and hitting 40mph on level ground, so I'm not sure what benefit I might have gotten if I had.

viney266 · Post by **viney266** » Wed May 08, 2013 4:09 am

Not a bad idea to throw a little in for the first tank, but after that? No need on a buddy 50. Those oil pumps are very reliable...A big bore Stella can be a different story, and a whole different argument .

rentonhighlander · Post by **rentonhighlander** » Wed May 08, 2013 2:34 pm

My understanding is that the oil injection system on these things are solid unlike some of the oil injection systems you might have found in the past. I was just interested to see if anyone premixed and under what conditions.
My experience is similar to the one above, although with far fewer miles. I just passed 3700 miles this morning and should log about 5k my first year and I get 80 -90 mpg and can go about 40 mph as well. I'll be very pleased if I can get anywhere close to 20k.

JohnKiniston · Post by **JohnKiniston** » Wed May 08, 2013 3:24 pm

I would recommend against it. Adding oil to your gas will change your jetting making the bike run leaner which can lead to a seize.

Your bike has oil injection and is designed to use it.

rentonhighlander · Post by **rentonhighlander** » Wed May 08, 2013 6:43 pm

I'm not sure that I follow you. If you premix oil with your gas in addition to the oil injection system you would be running rich.

Lokky · Post by **Lokky** » Wed May 08, 2013 6:46 pm

rentonhighlander wrote:I'm not sure that I follow you. If you premix oil with your gas in addition to the oil injection system you would be running rich.

nope, the same volume of gas/oil mixture would go to the engine, but the gas content will be lower because you increased the oil content, therefore you'll be running lean.

JohnKiniston · Post by **JohnKiniston** » Wed May 08, 2013 6:51 pm

Nope, You'd be running lean not rich.

Your reducing the amount of fuel going through your jets by how much oil you mix into your gas, So if you mix to 50:1 you go from 100% fuel going through your jets to 98% fuel going through your jets. Thus leaner.

rentonhighlander · Post by **rentonhighlander** » Thu May 09, 2013 1:36 am

Less gas is going to your engine but more oil (oil from premix and oil from injector). It is the oil that keeps it cool. Your air to fuel ratio should not change. Perhaps I should not have used the term rich and lean because that is your fuel to air ratio.
With premix added to your gas and your injector in operation your engine would be burning more oil (smoky). I used the term rich (inappropriately) to convey that the engine is using more oil and thereby cooler which is similar to a rich condition. When a engine is running rich it is running more fuel which delivers more oil.

JohnKiniston · Post by **JohnKiniston** » Thu May 09, 2013 3:07 am

Oil's just a lubricant on a 2-Stroke, It doesn't cool the engine. The charge of fuel coming in may cool the engine but if your leaning out your mixture your going to be running Hotter not cooler.

Now on a bike like the 4-Stroke buddies the oil is lubricating the engine and cooling it as it is pumped through the engine, They even have a tiny oil cooler under the floorboards to cool it down before it goes back into the engine to pick up more heat.

And still, The more oil you put into your gas tank the less fuel you have in your gas tank. You can't richen your mixture by adding oil, you can only lean it out by adding oil. And if you have oil injection you really shouldn't be putting oil in your gas tank except for in a few special cases.

rentonhighlander · Post by **rentonhighlander** » Thu May 09, 2013 3:39 am

As you state a lubricant reduces friction, which thereby reduces heat.
In this case the oil is also the fuel.
The air to fuel ratio does not change unless you change your jets.
Try running your engine with no oil and see what happens. It will seize.
If you run your engine with too much oil it will not seize.
Seizing occurs when an engine overheats and the rings melt to the cylinder wall. This will not occur with too much oil.