I'm looking for a 0W/5W-40 oil containing friction modifiers that give it a lower friction coefficient than necessary for usage in a wet clutch. Which of the most widely available oils meet this criterion (or which should be avoided)? In this viscosity grade, are most synthetic HDEOs wet-clutch compatible while most Euro PCMOs are not?
Which 0W/5W-40 Oils are NOT Wet Clutch Compatible?
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From my Harley days, anything that says RACING oil on it. Too much anti friction additives.
Is this for a motorcycle having a single oil sump for engine + transmission + wet clutch?
If so, I've owned several over the years. They usually said not to use oils that are marked as "energy conserving". Usually, Xw30 and thinner are energy conserving, Xw40 and higher are not. But of course you need to check to be sure.
Why 0w/5w-40 viscosity? Is that what the engine calls for? I had good results with Chevron Delo 15w40 and Mobil 1 15w50. No operational issues (smooth shifts, good clutch operation) and clean UOAs.
If so, I've owned several over the years. They usually said not to use oils that are marked as "energy conserving". Usually, Xw30 and thinner are energy conserving, Xw40 and higher are not. But of course you need to check to be sure.
Why 0w/5w-40 viscosity? Is that what the engine calls for? I had good results with Chevron Delo 15w40 and Mobil 1 15w50. No operational issues (smooth shifts, good clutch operation) and clean UOAs.
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JASO MA and JASO MB classifications - oilspecifications.org
To clarify my comment above about energy conserving: with the bikes I owned, the manual said that if the API donut has the text outlined in red below, don't use it. It used to be called "energy conserving" but now is called "resource conserving".
This has been discussed before.
Whether it is still true today... I don't know. Has JASO certified any resource conserving oils?
This has been discussed before.
Whether it is still true today... I don't know. Has JASO certified any resource conserving oils?
any proof to this statement? I wanted to refute, but I also don't have proof. My gut just says this is not the case.
OK, but back "in the day" 60W Valvoline Racing Oil cost me a clutch pack.
Now, yes, that is only one example, and who knows it may not even hold true today due to the different additives. These days racing oils may not need tons of moly or zddp. I'd still steer clear of racing oils for wet clutch motorcycles unless it meet JASO spec.
Now, yes, that is only one example, and who knows it may not even hold true today due to the different additives. These days racing oils may not need tons of moly or zddp. I'd still steer clear of racing oils for wet clutch motorcycles unless it meet JASO spec.
Simple. If labeled “energy conserving”= No Bueno.
For a combined engine clutch tranny, anything JASO. No JASO, No Bueno.
I'm not so sure. Mobil 1 15w50 and Chevron Delo both worked great in my motorbikes, and to my knowledge neither is JASO. (I could be wrong?) The manuals for my bikes did not say the oil had to be JASO certified. They only said it should be Xw40 or Xw50 weight, API SN (or whatever) and not energy/resource conserving.
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For our race bikes I make 100% it says wet clutch compatible at least for the clutch side
We run Lucas JASO rated in various weights
.....yes I'm prepared for the Lucas bashing to ensue
We run Lucas JASO rated in various weights
.....yes I'm prepared for the Lucas bashing to ensue
Thanks, everyone. I specifically want to avoid oil that is wet clutch compatible. For example, Rotella T6 5W-40 has (or at least had) JASO-MA certification. Therefore I wish to avoid it. MRC01 indicated that Mobil 1 and Chevron Delo worked in his motorbikes, so perhaps I wish to avoid those too. Oils that are wet-clutch compatible have a friction coefficient that is unnecessarily high for my need. Which widely available 5W-40 oils have a lower friction coefficient?
Wet-clutch compatibility probably has something to do with shear resistance as well...
Why not just use any oil that is marked as "resource conserving" in the API emblem? My understanding is this indicates the oil has friction modifiers / lower friction coefficient. And, they happen to be incompatible with motorcycle wet clutches. However, it might be hard to find any motor oil heavier than 30 weight that is marked as resource conserving. Hence your conundrum.
What application is this and what does your owner's manual say for a specification?
Usually oil that is not marked 'resource conserving" is usually compatible with a JASO requirement, or will at least half way work in a wet clutch environment. Rotella 15w-40 met the JASO requirements long before they actually put it on the bottle. My point was, that while oils not labeled "resource conserving" would probably work just fine, those labeled with JASO are pretty much a guarantee there wont be a clutch issue.
Is this for a motorcycle? Which one?
It sounds like you are looking for oil for some other application than a motorcycle and should probably post this question in a different sub forum.
Look for JASO MB. MB means it meets all other JASO specs except for clutch friction specs and is meant for bikes without shared sumps.
See above.
I made plenty of "Racing" labelled oils that were just fine with clutches back in my day. "Racing" does not specify any particular performance; the idea is that it is high performance in some area at least though to make it better for competition. I made some that were very heat resistant, some that had extra wear resistance, some that were extra "sticky" on the clutch.....it depended on what I was trying to improve compared to the regular commercial version.
That being said, a "Racing" oil may be no good for clutches, just take it on a case by case basis to figure it out.
See above.
As a fellow engineer, I thought something similar. Thank you for adding details!
in all 3 manuals of my RACE bike - labeled by Yamaha for competition off-road use only - it says NOT to use
Energy Conserving II
oils
now...as i have not only asked but stated several times here on bitog over the last 17years.....show me a bottle of ANY oil that has
Energy Conserving II on it!
race oil...must be the cousin to race gas
lmao!!!
Energy Conserving II
oils
now...as i have not only asked but stated several times here on bitog over the last 17years.....show me a bottle of ANY oil that has
Energy Conserving II on it!
race oil...must be the cousin to race gas
lmao!!!
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