Oil and ratios

[bigbore]

I am a big believer of heavy oil usage.I run 32:1 in the 1980 YZ465.It's only on the 2 OS piston and it's no garage queen.Even with my 1984 RZ 350 (oil injected) I run the pump on the  heavy side.The photo is the head from the RZ after 13000 miles.Notice the lack of carbon.Also after 13K the pitsons were worn out.However the bore is striaght and true to the tune of 2 ten thousandths.Just like it was new.Rings were also worn out.The cylinder in my avatar is the one I'm talking about.This is no stock RZ,ported,head welded and remachined for the set-up,carbs.pipes,ect.Oh and the RZ has 40,000 miles (all but 1601 mine) on it and is 1st over.Been through a bunch of pistons and rings.Crank #3 is going in.Enough with the specs.
  I am an advocate of synthetics or the bean if you've the time to take care of it.I've spent a bit of time studying rheology,tribology and CFD so I can get a little deep about this.Synthetics simply work better .Better lubrication,little to no smoke even at high loads.I do not understand the current practice of thin oil ratios.I'll provide empirical evidence that more oil=more power.Click here and scroll down to the Cycle magazine article and download it.It's a photocopy of a 1978 article.Please read it.There's some other stuff worth checking out there too.

Here's the head.See the lack of carbon?The goo is oil pushed to the exhaust port by transfer wash.Wiped it off with a rag.



EDIT:The oil used in the RZ is Amsoil Interceptor.

[Recovered]

I can assure you that the oils from 1978 are not the same as today. That being said, premix ratios affect jetting. And from experience, most carbs are jetted from the factory for ratios closer to 20:1 than 40 or 50:1. So there is more to the "more oil is better" thinking than just the ratio.

So....................if you have spent some time with a certified tribologist you will know that for a commercially produced premix, they fret over viscosity. Not of the oil in the bottle, but how the oil, mixed with fuel changes the viscosity of the fuel. Oil is so complicated that to the casual observer it's simply ignored what technology there is in oil (of all types).

I never EVER go by what the owners manual says about premix ratio. I go by what the guy who blended the oil in the bottle say. So yes, I mix by the label. If it says 20:1 than that is what I do. If it says 80:1, I'll do that and jet accordingly. And there are problems with this. Most guys aren't tuners, don't understand all these things, and the comic book media won't teach it because I don't think THEY know it. Just look at Motocross Action mag. Guys actually write in and get TUNE UP  tips from them. Even though they don't ride at the same level, premix at the same ratio, ride at the same elevation and other factors. I think it's outrageous that MXA even attempts this jive. It's stupid, and does a disservice to 2 stroke riders by keeping them ignorant of their machines. I have no doubt that you can get an oil that will lubricate efficiently at ratios above 100:1. 99% of the market could not afford them. That same percentage of riders would have trouble with their tune up.

I don't want to come off as arrogant, because I am not. I am concerned with 2 stokes and how they are perceived in the world of motorcycles.

I spent more than 2 hours (that's a lot if you think about it) with a tribologist who works for a niche market oil manufacturer. That was some of the most educational time I spent on the phone ever. We covered additives that produce power, how THEY develop an oil, what they use for base stocks and friction modifiers (we talked about 4 stoke oils as well) and why, if properly lubricated, and engine will make the same power at any premix ratio, providing the tune up is corrected for the change of oil.

Man, I gotta write that book.................

[bigbore]

I've spent a lot of time with a flowbench screamin' in my ears,dyno tuning (2 and 4) and riding.Regardless of the oil's configuration more is better.Longer life,more power how could these be drawbacks?Empirical evidence is what matters.Everything works in theory but no one lives there.You basically have one problem.At,say 100:1 there physically is not enough oil to cover the territory.I don't care how good it is if it can't cover the parts it cannot lubricate.I have not yet met anyone,either rider or tuner who considered that.Combined with the horrible swill called fuel (loads of solvents) that we see now the lack of lubrication is critical.Care to discuss that aspect?

[Recovered]

As I have stated before...I don't try to out think the tribologist. I don't need to. As for needing enough oil to cover all regions: think of the volume of fuel that moves through the engine. Now consider that most guys have oil DRIPPING out the of the pipe (the dreaded spooge).

That is excess oil not used for lubrication. And it costs HP to run the crank in excess oil. Dyno experience should show that. That is why Pro Stock pans are huge, the oil pumps pull 15-20 inches of vacuum and they run low tension oil rings and back cut compression rings (among other things).

It's all academic. I'm not saying that at 100:1 you would not encounter problems in certain situations. Lets say a long high gear pull, followed by a low RPM, high load hill climb. At low throttle openings, the available oil is just not there.

I know there are oils that will work at super high dilution rates. I don't argue with the guys who design the oil.

There are also environmental concerns. Greater dilution rates use LESS oil overall. Synthetics also don't produce smoke when correctly tuned.

So everyone can bark about low dilution rates and lubrication, but until I see the spooge and smoke stop, it's all irrelevant. That's a waste of oil and HP.

[Recovered]

I didn't address your position about the "swill" called fuel (gasoline) we are stuck with today. I do not advocate race gas in a 2 stroke unless you have altered port timing, compression ratio and the pipe. You just don't need it. But you can't run "regular" either. The difference between the two is significant. I don't feel like typing it all out, but there are many reasons not to run race fuel in your bike. From timing and jetting issues to cost and power output.

However, I do use an additive that is not available anymore. There are good reasons to run pump premium for fuel in your dirt bike, especially if you ride year round. And these were expressed by a fuel manufacturer.

I also want to point out that 2 strokes require significantly LESS lubrication than do plain bearing applications. This is due to roller bearings on the crank and wrist pin.

[bigbore]

I'm just not seeing the spooge.Jetting is spot on and that makes a huge difference.And at 32:1 it smokes a bit cold,little to none warm.Again 2nd over at 29 years old.Seems like we'll just have to agree we disagree.And I won't even start about the benefits of heavily leaded oxygenated wonder juice and the power it produces.

[JETZcorp]

I've said it before, but my '67 bike is still running the original piston.  Not sure what our ratio is, but it does smoke a bit and isn't a garage queen.  This thing has been ridden half-way to the moon and back and continues to run well.  Again, I don't know what our ratio is, but we use Castrol and I can say it's a damn sight more than 40:1.

[Recovered]

I'm just not seeing the spooge.Jetting is spot on and that makes a huge difference.And at 32:1 it smokes a bit cold,little to none warm.Again 2nd over at 29 years old.Seems like we'll just have to agree we disagree.And I won't even start about the benefits of heavily leaded oxygenated wonder juice and the power it produces.

I don't consider 32:1 to be outrageous. I am premixing at 40:1, as per the manufacturers recommendation. Any non-synthetic oil is just not woth it, including bean oil, at any ratio, regardless of results. Jetting is the cause of 99% of spooge and smoke.

I said I use a fuel additive (not an additive but a conditioner), never commented on lead and oxygenation.

[AFG]

Madscientist I have to agree with you on some points, and disagree on others. I believe using the manufactorers ratio's are the best way to go in most situations. There is one however that I found I had much better results using extremely high ratios(60-80:1). This was with Trials bikes( low compression, mostly low revs), and these ratios worked well. I did however have my bikes jetted correctly. No bean oil? I have had very good luck with it. I just don't use it when it is below 40 degrees(seperation can occur at temps below 40). Below 40 I use a blend (Super M). On the fuel issue, I have always used race fuels (C-12 predominately, we are in VP's home town) based on the consistancy! I jet all my dirtbikes using the same fuel and oil,type,and ratio. I do not want my fuel, or oil to be a variables that change. The pump gas here is attrocious regardless of octane rating. My lawnmower doesn't even like it!

[juliend]

Smoke and spooge are indeed primarily a product of poor jetting, not "too much" oil. You can indeed use all that oil if the bike is jetting correctly for the mix being run. Assuming proper jetting for the mix used, I am with the "more oil is better" crowd. However I'm quite comfortable running at 40:1, especially for trail riding. I will NOT run 50/60/80/100:1 regardless of what the oil manufacturer claims.

Madscientist,

   I'm interested to read the info coming from your source in the oil industry. Should be interesting!

J.

[Helmut Clasen]

   Politics-Religion-Oilmix,.....we will never come to a common agreement
Its just not possible.
We have discussed it for many years,probably since engines are in the world.
It will never change.
But here a nice story out of my expirience.
ISDT Germany 1962.I am a team member for Germany.
My bike DKW 175 cc.Gas from ,oil from Castrol.Mix 20-1.(that was a common mix in this days).
Optimol Oil Werke,from Munich(just around the corner from Garmisch Partenkirchen),comes (for the very first time in Offroad competition) and makes us(our team) an offer.
They sponsor us with gas and oil mix.If we finish the ISDT we get a nice lump sum of money.(we all where hungry amateurs).
If we got a Silver or Goldmedall we would get even a lot more money and maybe a contract for the following season.
So whats the catch we where asking.
Well the mix will be 50-1.(oh shi......)
If we would have a oil related failure,we would get a brand new motorcycle of the same model.
After a team member meeting and discussion we decided to go for it.
All bikes got filled with there mix and we wend out for carb testing and tuning.After done that,we made a full power test in the mountins(ALPS).There was one thing right away we realised,the bikes startet very easy,had a crisp and healthy sound,and did not smoke.
Result after 6 days we all finished and I had my very first GOLD.
In 1967 I moved to Canada and in1970 a Canadian friend and distributor visited me in my shop to show me this new oil he was interestet to import,but,,,,he wantet me to test  my bike first,...because it has to be mixed 100-1.Yes it was OPTIMOL oil.It was a little shock because even now we where using oil mixes 50-1 but 100-1.???Well it worked and I never looked back.
Most important.Carb.set up.Constant gasoline and oil mix with the same make.

[admiral]

hot dog! an oil thread. where's the personal attacks?

[JohnN]

No personal attacks!! Please!! 

Really choosing the oil and ratio for a two-stroke is like picking a wife (or significant other) You like some and you may not like others, but there is no perfect one that everyone has to have!!

When it comes to oil and ratios, smile, relax, experiment and use what works for you!

On another note, I find Helmut's stories extremely informative and interesting, please keep them coming.

[admiral]

admin, i'm just kidding. every oil thread i've ever seen on the internet turns personal. i hope this place is different because honestly someone could run canolla oil for all i care.

[ford832]

hot dog! an oil thread. where's the personal attacks?

Since you asked,I'll start.I wouldn't give a mouldy hotdog for your your oil theories admiral-hee,hee.Hows that.Anyhoo,years ago MacCulloch,of chainsaw fame at the time,did extensive testing and found to best power/performance to be had at a ratio of 12:1.Mind you,oils today are obviously different but I always thought that was interesting.