Follower scar oil tests (2018)

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How do they do it?

There is the question; the $64,000 question.

The MA rated oil I looked at seem to have a moderate to high Phosphorus and Zinc additives. Thinking out loud, there are different lubrication regimes; the four main ones are:
  • boundary,
  • mixed,
  • hydrodynamic, and
  • elasothydrodynamic (rolling elements, gear teeth and cams)

Each regime probably has it's own unique means and methods to "more" slipperiness.

My point with the clutch is, in which regime does it slip? I doubt the point loading in a clutch comes anywhere near that of a flat tappet in boundary regime where the Zinc and Phosphorus additives are activated. The additives may contribute in other lubrication regimes but I have not read nor heard from others on it.

I think this point fits the thread here as my hunch is the test results presented here are probably looking at one lubrication regime in isolation - nothing wrong with that as I believe our Nortons may have special needs, be it lubrication or metallurgy.

This goes back to a link provided worntorn (you) provided earlier which I thought was an excellent point (assuming it is accurate):

https://mobiloil.com/en/faq/ask-our...trength-of-mobil-1-compared-with-royal-purple
 
I don't think the case has been made for friction modifiers causing the clutch to slip; well at least the Phosphorus and Zinc additives. Oil, not unlike an IC motor, seems to be a compromise, where the needs to address various lubrication regimes. With the friction modifiers, they are apparently there to primarily address the boundary lubrication regime. As engine designs change, so do the specific (or ideal) lubrication requirements.
As in any specialty, communication is often made difficult, or at least challenging, by the specific nomenclature employed by those intimately familiar with the technology area. From the recent flow of the discussion here today I am suspecting that we are experiencing this challenge, which can result in us talking apples and oranges rather than apples to apples.

I’m no more than an interested reader and have no expertise whatsoever in oil formulation, but from the reading I've done suspect the nomenclature of oil formulating and additives might be tripping us up a slight bit. Specifically, when we include ZDDP in the category of "friction modifiers", we have departed from the nomenclature employed in the industry – which may lead to misperception/misunderstanding as our conversation flows on. Although ZDDP does reduce friction, it is generally referred to as an anti-wear agent, not a friction modifier. The term "friction modifier" is reserved for a different class of compounds all together (these molecules are more surfactant-like with a polar head group and long fatty tail that self assemble on a surface, but are easily displaced under higher pressure).

I believe friction modifiers do in fact cause wet clutches to slip, and for this reason most (all?) motorcycle oils suitable for use with a wet clutch do not contain friction modifiers, but do contain ZDDP.

https://www.machinerylubrication.com/Read/28815/what-are-friction-modifiers

https://www.sciencedirect.com/science/article/pii/S0257897210003786

Hope this helps to clarify rather than muddy the waters further.
 
So in an attempt to unmuddy the waters, I am pretty sure "Friction Modifier" as it pertains to ZDDP etc. is in direct alignment with industry nomenclature.

In your machinery lubrication reference above WZ507 it is referred to as "a stronger type of friction modifier characterized as an anti-wear additive". A distinction that was not lost in my previous post of the lubrication regimes.

My point in my previous post was: what may be a targeted "Friction Modifier" in one (or two) lubrication regime(s), does little to nothing in another lubrication regime. An example might be a simple sleeve bearing running most of its life in the hydrodynamic regime benefits little from ZDDP whereas a cam over bucket four valve head might only need a less rigorous friction modifier whereas a flat tappet high spring load two valve head with an aggressive rocker ratio might need a "stronger friction modifier" (ie cubic meters of ZDDP per liter of oil):D

Important points of distinction that I hope do not get lost here.
 
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I have been running Amsoil DOMINATOR 15W-50 Racing Oil in my Norton specifically because I want to take advantage of the fact that the engine oil does not need to be a clutch oil. The zinc level is high and it has the low friction additives. I'd like to see it tested as weil. If it is not too late to climb on board I'll send a quart over.
 
All this oil specification chat is really great reading but.....
As synthetic oils shouldn't be used until everything is bed in... what is the best mineral based product to be used at run in ???
 
Depends on the engine build, if you use cast iron rings and hone correctly then you need the rings to wear against the hone to bed in, synthetic oil will not allow this to happen so the rings do not bed in.
 
Here is my new oil testing setup. It now has the ability to test a wide range of film strengths.

One thing I have learned is some motor oils tend to create a stronger film as the temperature gets into the normal operating range, so now all the testing is done at an oil temperature starting at 190 f. As the follower load increases the oil temp rises above 190 due to friction.

 
I have been running Amsoil DOMINATOR 15W-50 Racing Oil in my Norton specifically because I want to take advantage of the fact that the engine oil does not need to be a clutch oil. The zinc level is high and it has the low friction additives. I'd like to see it tested as weil. If it is not too late to climb on board I'll send a quart over.

I would like to see that one also, so send it on over.
 
Oh dear !!!!
So your thoughts on that HD50 result?
Regards Mike

I would say it is not suitable for a high performance Norton engine. Roller followers may be fine.
It looks like it is comparable to the VR1.
 
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Thanks Jim, wonder how the high performance race cars using flat tappets are a proponent of the Driven oil.
I am thinking maybe the HD 50 is no where the same spec as what is used in car engines.

Back to more research for me for my race motor.

Do you have access to this type? Torco TR 1 MPZ 10W40

I have a drum of it and using it in my roadbike which has just had a freshen up with rings and bigend shells.
Break in was done with Driven BR oil.
http://www.drivenracingoil.com/dro/br40-break-in-10w-336html/
Regards Mike
 
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I am thinking maybe the HD 50 is no where the same spec as what is used in car engines.

Do you have access to this type? Torco TR 1 MPZ 10W40

Regards Mike

I suspect your right in thinking the motorcycle oil is not the same as the car oil, but I don't know.

I will look for the Torco oil. I used it back in the 60's .

Actually the Motul 300v 20-60 is closing in on the Royal Purple as we speak.
 
Thanks Jim, Im just about to fit that Fullauto head that I got off you (No #10) to see if I have Vv to Vv clearance with the JS2 cam and once that is done, Im ready to run it.
So be good to go with a better oil if I can get my hands on something thats not cost restrictive.

http://www.staparts.co.nz/View-A-Pr...le XPR racing oil 51 20W50 5gal (18.9L) 05051

Doug McCrae said he used a Motul synthetic in his race bike, although said it was so slippery it got passed seals!!!

Thanks for all your had work on this.
Regards Mike
 
Hi Jim, your graph sheet has the ID as Castrol, although you wrote Valvoline in your notes?
Is it one in the same?
Regards Mike
 
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