premix?

[Suzsmokeyallan]

Doug as posted before the ratio back in the days of the older bikes was a 20:1 however today its more commonly used at 32:1

[doug rooney]

Ok, Thanks much Suz!

[Buffalo-guy]

Using conservative math, at highway cruising, and general riding pace, I use oil at about a 58 to one ratio. The oil pumps on the triples, at least, tend to wear the contact point where the cam and piston body meet, literally lengthening the stroke of the pump at moderate throttle position. I have always turned back my pump setting because of this, and have never had oil volume problems. A little blue haze at cold start up, and runs like a four stroke on the highway. Average 7-800 mi per quart of injector oil. Happy bike. The synthetic injector oil I use (Amsoil) is rated for 50-1 ratio as premix, so you don't need huge amounts to protect your engine, and as was said, one tankful at most should be more than enough to get the stock system stabilized. More opinions on the way, I'm sure. Cheers.
Fred

[doug rooney]

Thanks Fred. I'm sure learning a lot about 2 strokers and their oil. I always thought that if they weren't smokin heavy, there was a problem. I guess more is not better eh?

[tz375]

The regulars would be disappointed if I didn't jump in at that remark. Every test so far has shown that within reason, more oil makes for more power and less deposits.

Anecdotal evidence suggests the contrary, but so far I am yet to read the tests that support that supposition. So for now, more is always better.

In fact I think it's time for a new way to look at this whole oil thing. The NEW WAY is to see ol as like Breasts. Yes you heard me. Within reason, more is always better. Some people will always prefer less and others will rationalize why their choice of shape or other peculiarity has appeal.

For the rest of us more is better. See I knew there was a simple way to look at this that we could all understand and agree with (yeah right.)

As the old saying goes, nothing exceeds like excess

[doug rooney]

You guys are making me CRAZY! LOL! I'm going with MORE!

[Suzsmokeyallan]

Dont we all just love oil forums, the opinions for and against keep getting rehashed,,LOL. What i'd like to know is what youve seen on the internals your various engines you ran on your "more oil" ratios Richard.
My ratio tests ive done on a few engines over the years consistently show that adding more oil than the manufacturers recommended amount is not any better, However ive tried my own little tests to seen how the results vary on the engine parts with 16:1 20:1 32:1 and 50:1 ratios.
It is however all a personal choice on the owner and what they are prepared to live with as a result of it.
Always remember, more oil in the same percentage of gasolene IS a leaner mixture.

[rbond]

I agree, MORE BREASTS is better!!!!!!!!

[TLRam1]

I copied this from a post at Kawak Site.

This might answer or confuse the subject further.

Here's a little info. on the subject:

There are a few good reasons to run a fuel/oil mix at ultra thin ratios in a two stroke. High ratios such as 100 to 1 are usually environmental reasons, such as for outboard boat motors. The exhaust of an outboard motor goes directly into the water, and environmental­ists are worried about the oil in the mix polluting the lakes and rivers.

There’s a myth that the less oil you use in your gas, the more horse­power you get. Conversely, many dirt riders actually forget to put any oil whatsoever. We know of one guy who forgot to mix oil into his gas and actually rode it for two hours without seizing it. All the bearings were ruined and the piston was worn out, but it didn’t seize!

Actually, you can get more horsepower out of a two-stroke engine with enough extra oil in the gas, because the oil provides a better ring seal and, therefore, more compression. People think that gas burns more efficiently with less oil, and therefore you get more performance. It almost makes sense if you look at that one statement alone.

The seal of the piston is critical. If you remove the lubricants from the gas, the viscosity of the mixture becomes lighter and more prone to vaporization. With a lean mixture, there is less oil to seal the rings. The sealing of the rings has more to do with the performance of the engine than the possibility of having better-burning gas with an ultra-lean gas/oil ratio.
The old fashioned two-stroke oil that was on the market years ago, was designed to be run at 20:1 and was basically petroleum with a few (very few) ad­ditives. Then, when high-per­formance oils came along, they cost more to make and sold for a higher price. They got into these high mixing ratios in order to jus­tify the higher prices.

If you do foul plugs, it is more than likely caused by poor jetting, not a bit too much oil. If you get your bike jetted correctly, have a fresh plug and a strong ignition system, you won’t foul plugs.

When the motor is idling, or at lower rpms, that’s when the machine has a greater chance of fouling a plug. Minibikes and 125s have even less chance of fouling plugs, because they are ridden at such high rpm. Because of the ultra high rpm, the load on a given part is much higher on a 125, than on an Open bike.

Plugs should not foul at richer ratios if you are using high-quality oil in the mix. High-quality oils will have a good detergent/dispersing package that holds down the contaminants which produce plug fouling.

A typical example: you go from a 50:1 ratio to a 20:1 ratio. Your engine will now run leaner, and you’ll have to make jetting changes. You’ll need bigger (in number) jets because the oil molecules are thicker and the flow rate (the amount coming through the jet) is less.

Aha! The volume of fuel has changed. The oil takes up some volume that the gas used to occupy, so your engine is getting less gas and needs to be richened up.

So which ratios should two-stroke gas/oil should be mixed? A properly jetted engine will run better, last longer and develop more power at a lower oil ratio than at a higher one. But what is the proper amount, and how do you know a quality oil from a bad one?

The ratio a rider should use in his two-stroke will depend on the size of the machine and the type of riding being done. An 80cc racer will require much more oil in the mix than a 500cc play bike. The best bet is to consult the owner’s manual and follow the advice of the engineers who designed the motorcycle.

As for which oil to buy, that depends on the type of riding being done. Someone who races will require a higher-quality oil for its superior ingredients and properties, than someone who only play rides and doesn’t put a lot of strain on his engine. A good, high-quality oil will cost more money than a poor-quality oil, because of the higher cost of ingredients, such as synthetic diesters and ash less detergent dispersing packages. Quality ingredients cost more money, and that makes the quality oils more expensive.

Our advice then, is to buy a quality oil and run it at a moderate ratio. We’ve used 32:1 for many years. In race bikes that are ridden hard, we might go a trifle richer at say … 28:1. For a trail bike, 40:1 would be the way to go, assuming that you used a quality oil. If you own a mild-mannered bike, consider a 50:1 ratio.

One of the things you should do, is run high octane gas with any two-stroke mix. When all of the two strokes (the old days) were developed, they all used Castrol petroleum oil at a 20:1 ratio and found that 92 octane gas had the octane reduced to 72 with presence of that much oil. Modern oils won’t affect the fuel quite as much, but if you started with 86 or 87 octane regular fuel, you can see where you’ll end with a very low octane mix. You could end up with a “pinging” bike.

Race gas? You don’t need it in your two stroke unless you’re a pro or expert, and most expert level riders are on the new generation four strokes.

Gordon Jennings once ran a test for "Cycle", examining the effects of various oil mixing ratios on things such as plug fouling, horsepower, wear, varnish/deposits buildup etc. The guinea pig (guinea bike?) was a Suzuki PE250 if I remember correctly- correct me if I'm wrong. End result was, "more is more" i.e. more oil = more horsepower. I'll have to dig up that issue to refresh my memory regarding the full results as to the various aspects examined.

http://www.bridgestonemotorcycle.com/do ... remix6.pdf

[TLRam1]

Why can a fouled plug not be brought back to life? I have always understood this to be the case but not sure why and what exactly a fouled plug.

I always thought it was a plug shorting out due to deposits, dirty, etc. but never understood why the plug could not be cleaned and reused.

NGK states the same;

Q: What is a "fouled" spark plug?

A: A spark plug is considered fouled when the insulator nose at the firing tip becomes coated with a foreign substance such as fuel, oil or carbon. This coating makes it easier for the voltage to follow along the insulator nose, leach back down into the metal shell and ground out rather than bridging the gap and firing normally.

Fuel, oil and carbon fouling can all be the result of different causes but, once a spark plug is fouled, it will not provide adequate voltage to the firing tip and that cylinder will not fire properly. In many cases, the spark plug cannot be cleaned sufficiently to restore normal operation. Therefore, it is recommended that a plug be replaced once it is fouled.

[tz375]

Terry,

Thanks for adding those two quotes. As for why can't a fouled plug be cleaned, i don't know, but it is true more often than not. In my experience if a plug fouls, it often cannot be persuaded to fir again. Sometimes I can clean them or wash them in acetone or alcohol, but it doesn't always work.

I wonder if the oil soaks into the porcelain and causes the spark to track.

[TLRam1]

Here is the test copied from the Kawak site, the second has the test HP.

Here is the Jennings article: