Yes agree, that's what I was saying in the post above. It's all about gas mileage. Same engines around the world that we run a 20 weight in, call for heavier weights that guys are always asking whether running those will destroy their engine or not, LOL
Energy/Resource conserving oil not allowed? Why?
- Thread starter dole
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I'm not an oil expert/tribologist by any means, so take the following with a block or two of salt licks. My current understanding (open to potential revision) is that the primary differences between passenger car and motorcycle oils is that the latter have a higher ratio of ZDDP to moly, boron, and/or antimony based compounds (and also of course tend to be higher viscosity).
The ZDDP at the right levels, actually induces some friction which is good/necessary for clutches. The higher viscosity tends to induce some friction too. Whereas higher levels of moly, boron, and/or antimony reduce friction/increase lubricity. Having some of the latter in a motorcycle oil, as long as it is not too high and the levels of ZDDP are high enough to counter balance these, is ok. I've already seen a few motorcycle wet clutch oils which have some moly, boron, and/or antimony.
I compared the VOA's of a motorcycle specific Amsoil product-the 20w-50 V-Twin oil vs Mobil 1 Euro 0w-40 FS oil and was surprised to see that the latter car oil actually had a 3.5% higher ratio of ZDDP to moly and boron compared to the Amsoil product. The Amsoil product had a bit higher ZDDP overall, but when you added up the moly and boron content, it had a lower ratio of ZDDP to total moly+boron than the Mobil 1 oil (consequently, I have used the Mobil 1 in my bike during the colder part of the year with no issue, just recently switched it out for some Motul 7100 15w 50 for the hotter temps).
There are other factors which can affect the above equation. Really high calcium tends to reduce friction, while higher magnesium tends to increase it some. As mentioned, viscosity itself affects frictional characteristics some. Some bases have higher lubricity than others innately. An older bike with original clutch pack, fed a constant diet of conventional oil, might not fare as well with a fully synthetic oil, even if it is motorcycle wet clutch rated.
With all this said, I have questions of my own as to specifics, like the effects of mixing a smaller amount of a higher viscosity but energy conserving oil with a wet clutch rated oil. But I will start a separate thread for this.
The ZDDP at the right levels, actually induces some friction which is good/necessary for clutches. The higher viscosity tends to induce some friction too. Whereas higher levels of moly, boron, and/or antimony reduce friction/increase lubricity. Having some of the latter in a motorcycle oil, as long as it is not too high and the levels of ZDDP are high enough to counter balance these, is ok. I've already seen a few motorcycle wet clutch oils which have some moly, boron, and/or antimony.
I compared the VOA's of a motorcycle specific Amsoil product-the 20w-50 V-Twin oil vs Mobil 1 Euro 0w-40 FS oil and was surprised to see that the latter car oil actually had a 3.5% higher ratio of ZDDP to moly and boron compared to the Amsoil product. The Amsoil product had a bit higher ZDDP overall, but when you added up the moly and boron content, it had a lower ratio of ZDDP to total moly+boron than the Mobil 1 oil (consequently, I have used the Mobil 1 in my bike during the colder part of the year with no issue, just recently switched it out for some Motul 7100 15w 50 for the hotter temps).
There are other factors which can affect the above equation. Really high calcium tends to reduce friction, while higher magnesium tends to increase it some. As mentioned, viscosity itself affects frictional characteristics some. Some bases have higher lubricity than others innately. An older bike with original clutch pack, fed a constant diet of conventional oil, might not fare as well with a fully synthetic oil, even if it is motorcycle wet clutch rated.
With all this said, I have questions of my own as to specifics, like the effects of mixing a smaller amount of a higher viscosity but energy conserving oil with a wet clutch rated oil. But I will start a separate thread for this.
Zinc is a great anti-wear additive for the valve train. Only problem nowadays is it will plug catalytic converters if the engine is burning oil. Therefore zinc levels have dropped back considerably and moly and boron which perform similar functions are being used. As well, zinc is a protection of last resort. Only when things have gotten really bad does it become sacrificial. It does nothing at startup or under normal use.
Moly and boron are both active from the moment the engine starts up.
As far as zinc contributing to clutch grip, this is the first time I've heard this in 30 years of riding motorcycles. Because zinc is inactive unless under extreme pressure such as in the valve train when the oil has basically failed from extreme heat, pressure and lack of film, I don't see it contributing to clutch grip when looked at in the context of the different plates and force already designed into a clutch.
Moly and boron are both active from the moment the engine starts up.
As far as zinc contributing to clutch grip, this is the first time I've heard this in 30 years of riding motorcycles. Because zinc is inactive unless under extreme pressure such as in the valve train when the oil has basically failed from extreme heat, pressure and lack of film, I don't see it contributing to clutch grip when looked at in the context of the different plates and force already designed into a clutch.
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Hi Bonz, I'm basing that off of some things that Lake Speed Jr. has said about ZDDP--repeating that ZDDP tends to both increase friction and reduce wear in the right amounts (though if too high can cause more wear and/or damage).
I'm aware that at high temps, ZDDP forms a glassy phosphorus coating on metal surfaces. But is that all it does? Because I would think that would only tend to reduce friction, not increase it. I've wondered if in the particle state, it has a gelling like affect (sort of like, but different than, a polymer based viscosity index improver)? I wonder that for a few different reasons. One reason is that I was actually looking up reviews of a ZDDP increasing additive recently, and one of the reviewers noted that after he poured out the contents of the small bottle, there was left behind this thick, goopy, snotty like residue and he was wondering if perhaps that is where most of the ZDDP was actually at. (the product was a single bottle of Rev X on amazon btw).
Again, I'm no expert, but I do like to connect the dots and question. I have been trying to figure out what the difference between regular car oil and wet clutch motorcycle oil is for awhile now, and I don't believe it is solely as simple as motorcycle oils always have much less moly, boron, and/or antimony. But I may be wrong. But I do note a few major repeating patterns in the real world, 1. motorcycle oils tend to have higher ZDDP levels than car oils, 2. they have lower amounts of moly, boron, and/or antimony generally, and 3. they tend to be higher viscosity. And I have wondered if there is a synergistic affect from those 3 common differences? I'm fairly new to this whole "obsessing about oils" thing though.
I guess to know for sure, someone would have to consult a tribologist(s) who has been involved in formulating wet clutch motorcycle oils. It would be great to be proven correct or wrong on this. But I rarely ever hear anyone discuss the mechanics of why they are different, but just the repeated dogma of, "you can't use car oils in wet clutch motorcycles because". At most, I hear about friction modifiers, and yet I've seen some (even high quality Amsoil) motorcycle oils with decent levels of moly and/or boron. I've never been satisfied with surface level dogma, and have a need to know the exact why's.
I'm aware that at high temps, ZDDP forms a glassy phosphorus coating on metal surfaces. But is that all it does? Because I would think that would only tend to reduce friction, not increase it. I've wondered if in the particle state, it has a gelling like affect (sort of like, but different than, a polymer based viscosity index improver)? I wonder that for a few different reasons. One reason is that I was actually looking up reviews of a ZDDP increasing additive recently, and one of the reviewers noted that after he poured out the contents of the small bottle, there was left behind this thick, goopy, snotty like residue and he was wondering if perhaps that is where most of the ZDDP was actually at. (the product was a single bottle of Rev X on amazon btw).
Again, I'm no expert, but I do like to connect the dots and question. I have been trying to figure out what the difference between regular car oil and wet clutch motorcycle oil is for awhile now, and I don't believe it is solely as simple as motorcycle oils always have much less moly, boron, and/or antimony. But I may be wrong. But I do note a few major repeating patterns in the real world, 1. motorcycle oils tend to have higher ZDDP levels than car oils, 2. they have lower amounts of moly, boron, and/or antimony generally, and 3. they tend to be higher viscosity. And I have wondered if there is a synergistic affect from those 3 common differences? I'm fairly new to this whole "obsessing about oils" thing though.
I guess to know for sure, someone would have to consult a tribologist(s) who has been involved in formulating wet clutch motorcycle oils. It would be great to be proven correct or wrong on this. But I rarely ever hear anyone discuss the mechanics of why they are different, but just the repeated dogma of, "you can't use car oils in wet clutch motorcycles because". At most, I hear about friction modifiers, and yet I've seen some (even high quality Amsoil) motorcycle oils with decent levels of moly and/or boron. I've never been satisfied with surface level dogma, and have a need to know the exact why's.
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I've been using PCMOs in wet clutch motorcycles for half a century. The only clutch trouble I had was on a very high mileage (80K miles +) clutch pack, which was likely caused by the 40 year old OEM factory springs losing some grip. Life's too short to puck around, so as part of the top end rebuild, I put in new frictions and springs.
However, just out of caution, I've been avoiding PCMOs with "energy conserving" written on them, but that's a relatively recent thing. I have no shortage of good oil stocks that will see me out.
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Hi Dave, yeah, I've used a car oil in the bike already and it was fine. I used Mobil 1's Euro 0w-40 FS oil. I did check out a VOA before I used it. That oil has decent levels of ZDDP and moderate levels of moly and boron, so I figured it would likely be ok. I compared it to an Amsoil motorcycle specific product, and was surprised that the Mobil 1 actually had a 3.5% higher ratio of ZDDP to total combo of moly and boron than the Amsoil product. I got 6 quarts on sale for like $32-I only plan to use it during the colder part of the year.
From what I've read here, that specific Mobil 1 product is supposed to be pretty high quality, not quite boutique level like HPL, Renewable Lubricants, etc, but not terribly far behind either.
Generally I plan to avoid energy conserving oils as well, with the exception of Renewable Lubricants super heavy duty 15w-40 diesel oil. I have a gallon of it and plan to try it out. It's a very high quality oil, mostly ester and PAO, with a unique and robust add pack.
From what I've read here, that specific Mobil 1 product is supposed to be pretty high quality, not quite boutique level like HPL, Renewable Lubricants, etc, but not terribly far behind either.
Generally I plan to avoid energy conserving oils as well, with the exception of Renewable Lubricants super heavy duty 15w-40 diesel oil. I have a gallon of it and plan to try it out. It's a very high quality oil, mostly ester and PAO, with a unique and robust add pack.
Thanks Versys, nice response. I agree too much of a good thing or not enough can be detrimental on either end of that spectrum. Red line runs 2,200 PPM of zinc in their MC oil, I've never had an issue with excessive wear that showed up in analysis compared to oils that had a 1,000 PPM of zinc.
Did Lake speed Jr show results of a test that increases zinc to the point of increasing wear? I worded it that way because increasing friction is increasing wear. Friction is the downfall of all things mechanical as they age.
Did Lake speed Jr show results of a test that increases zinc to the point of increasing wear? I worded it that way because increasing friction is increasing wear. Friction is the downfall of all things mechanical as they age.
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Specifically in relation to motorcycles, no, I don't think so, but he does have a few videos talking about ZDDP/zinc. This is one that goes into depth about too much zinc contributing to premature wear:
I haven't watched it in awhile and don't remember all the specifics.
I didn't see any input from the OP, but I'm interested - why would you put PCMO in a bike or a scooter, when there are plenty of motorcycle oils specifically designed for that purpose?
Energy/resource conserving oils usually have low viscosity and especially low HTHS index, which is much higher in motorcycle oils. I think resource conserving oil are not allowed in motorcycles because they are not robust enough for the application, nothing to do with the wet clutch.
Mobil 1 0W40 Euro formula is very robust ACEA A3/B4 oil (it's oil designed for turbo VW, MB, and Porsche) and is not resource conserving oil, so that doesn't answer the OP question.
Motorcycle oils always have much higher HTHS index, more zinc and phosphorus, and sometimes even higher TBN than PCMO, especially much more than resource conserving oils. Most resource concerning oils have max HTHS at 3.0 mPa.s, where motorcycle oils have at least 3.5 mPa.s. 0W40 FS (Euro) also has HTHS of at least 3.5 mPa.s. This is the one of main differences with resource concerning oils
For the same reason M1 5W30 ESP is a very robust oil because is rated as ACEA C3, which means HTHS of at east 3.5 mPa.s. And for that same reason it's a high viscosity oil with KV (100*C) at 12.00. The ESP oils also are not resource conserving oils.
You cannot have both optimum protection and resource conserving at the same time. That is why resource conserving oils are not allowed in motorcycles, scooters and small lawn engines. Those engines use much lower quantities oil and run at higher RPM for longer time than cars/trucks and for that reason the first need more robust oils. You may get away with resource conserving oils in them, but you are compromising the optimal lubrication.
ACEA certification (pages 4 and 5)
https://www.acea.auto/files/2021-ACEA-oil-sequences-light-duty-engines-rev1-2022.pdf
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