Follower scar oil tests (2018)

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Hillbilly Bike said:
There's been a lot of disussions about "scar tests" on auto racing forums...Many well experienced builders dismiss it as have no relevence to operating conditions inside the engine...And many lower rated "scar test" oils perform very well in actual running engines...
To each his own beliefs...
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Of course if you look at the scar testing done by most people it is far from the testing i did.

Most "scar testing' is very simple and more of a state fair sales gimmick. I probably never should have even mentioned scar testing with the testing I did....
 
comnoz said:
Of course if you look at the scar testing done by most people it is far from the testing i did.

Most "scar testing' is very simple and more of a state fair sales gimmick. I probably never should have even mentioned scar testing with the testing I did....
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Some people value myth over fact.
 
Silkolene 20w50 5 litres for 23 quid, if you the math(s) v 20 quid a litre oil, expected mileage to rebuild costs and riding life expectancy etc I suspect cheap oil changed regularly is a perfectly sensible option.
 
Hillbilly Bike said:
There's been a lot of disussions about "scar tests" on auto racing forums...Many well experienced builders dismiss it as have no relevence to operating conditions inside the engine...And many lower rated "scar test" oils perform very well in actual running engines...
To each his own beliefs...
Click to expand...

There may be just about as many “scar tests” as there are motor oils and depending on which test and the purpose of said test (to sell my product, my additive, my oil, etc) I’m certain you are correct that “scar test” results may be incongruent with actual durability of components in an engine. If someone were attempting to separate the wheat from the chaff in the vast ocean of “scar test” results, you’d likely start by eliminating those that were attempting to tie the sale of some product to the test results. In a similar vein, you’d certainly want an independent testing laboratory with no dog in the fight performing the test, e.g., The Norton Motorcycle Machine Shop. Then you’d want to scrutinize the test to assess whether it employed test conditions that replicated or at least related to some known application of interest, e.g., a flat tappet cam in a Norton engine. Upon further scrutiny if you found that the test actually employed a Norton lifter of known hardness running on a race of known hardness over a range of forces encountered in the subject engine, this should also be encouraging. And finally if you dug deeper and discovered more details of the test apparatus, such as…

Test employed a fully automated computer-controlled system
Test was well instrumented with thermocouples fit to the tappet body and oil bath that were monitored continuously
Test was performed over a wide range of realistic and carefully controlled oil temperature (220-320F)
Test employed a temperature controlled oil bath with both heating and cooling capabilities where both parameters were monitored continuously to provide a means of assessing the heat flow into the oil from the work performed at the tappet/test race interface
Test continuously monitored motor load to assess friction at the tappet/test race interface

And then considering all the foregoing, one might at a minimum conclude that not all “scar tests” are quite the same. But of course in the final analysis I couldn’t agree with your statement more, i.e., “to each his own beliefs...”
 
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In my opinion, what Jim has been doing seems like a reasonable approach given the numerous recent threads on the subject of Norton big twin cam/follower wear durability. I agree that it is more or less a point measurement (cam/follower/oil behaviour) even though conditions such as speed were varied. I for one appreciate Jim's efforts.

I suppose if one wants the whole picture they would conduct an oil analysis on a freshly built road bike for every 100 miles up to say 1,000 miles then every 1,000 miles through to rebuild time. One can generally trace the alloy particles (babit, cast steel, stellite, bronze bushing, etc..) to different components in the engine and plot wear rate. Do this several times to show repeatability for each type of oil tested.

Any takers on this? Didn't think so.

I also suppose this holistics type of oil testing has been done on comparable air cooled engines and those results would provide some insight and enlightenment provided they are not biased.
 
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Hillbilly Bike said:
There's been a lot of disussions about "scar tests" on auto racing forums...Many well experienced builders dismiss it as have no relevence to operating conditions inside the engine...And many lower rated "scar test" oils perform very well in actual running engines...
To each his own beliefs...
Click to expand...

So you dismiss the results of a scientific test designed to measure oil performance between cam and follower, in favor of the generalized thought that some oils, "perform very well"...?? Sorry, by what criteria do you conclude that an oil performs very well?...

If you followed the thread, you would know that Jim didn't rule out "good enough oil performance" from a large portion of the tested oils for use in stock applications. I took away from the test that his goal was to compare oil performance by measuring the pressure and temperature at oil failure so he could have better oil choices for engines which have higher than normal stress at the cam/follower interface. I wouldn't dissmiss his scientific test results in favor of a less scientific "to each his own beliefs" generalization. I do think he showed something significant about choices of oil... because of the science........ . . .
 
I used the Millers pistoneze semi synthetic 20w-50 for 3000 miles including 5 hours on a day that saw 39 C. It was cooked by the time I drained it and took off the top end and barrel, but surprisingly the internals where just like the day they were put in.
I now have Millers full synthetic POA 10w-60, I have run this for well over 3000 miles and the top end is coming off soon. I have noticed that I have a lot less oil vapour from the oil tank with this oil, does not run so hot in the cold weather which may not be ideal. For the cost I might switch back to the cheaper pistoneze as it does the job I need it to do.

No matter what test is utilised to test the oils, the fact the test was constant for different oils, would surely suggest that the results obtained are ideal for comparison.
Some times some of the best oil may be the worst enemy for an engine, you can see this in the testing that the likes of Toyota and Honda found when synthetic oils were becoming popular in the 80's. Surface finish was found to be critical with some oils that were tested then.
The variables of when an oil is used are huge, surface finish and treatment, clearances, temperature, engine speed etc, so even the most complex test may not prove any better than what Jim has done, both tests would still only produce a comparison list.
The best bit of the list, is that some will now use some of those oils listed and test them in a bike to test them further.
 
I don't think anyone would argue against the idea that the best test of oil in an engine is running that oil in an engine for X thousand miles and checking clearances/deposits before/after. That is commonly done by major engine manufacturers who have the resources to run engines various loads for extended periods - as in 100,000 miles or equivalent - and do such checks but is not feasible for folks without such resources.

I readily admit that when Jim first started this test and talked about scar testing, my reaction was pretty much as HillBilly pointed out - it doesn't relate to how engine oil functions in an engine. None of the major components in an engine interface in a way that typical "scar testing" duplicates. But, as he further pointed out, what he did wasn't really a "scar test" and, as he also points out, maybe a different term for his test would have been better.

BUT, to be fair, I can understand - and agree with - someone who says (typical) scar testing is not relevant to engine operation/engine oil performance. It is, however, an excellent marketing technique. ;)
 
Steves said:
Silkolene 20w50 5 litres for 23 quid, if you the math(s) v 20 quid a litre oil, expected mileage to rebuild costs and riding life expectancy etc I suspect cheap oil changed regularly is a perfectly sensible option.
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Jim’s summary of Silkolene Pro 4 20w50 was “Medium load capacity along with high heat would not make it a good choice for a Norton”.

I used it previously until one day at Mallory Park, after a days riding on new oil the oil pressure warning light came on on my BSA R3 powered bike. Much doom and gloom engulfed me as I pondered (another) hideously costly engine rebuild.

Loooong story short... it was the oil. It had overheated and broken down to the point that it couldn’t even provide enough pressure to keep the oil light off. Goodness knows what would have happened if I’d have kept riding it with that degraded / broken down oil in it.

Jim’s test bench conclusion and my own empirical evidence seem to corroborate each other completely.

It’s probably great in a modern water cooled engine, but I’ll not be putting any in any of my old bangers again.
 
o0norton0o said:
So you dismiss the results of a scientific test designed to measure oil performance between cam and follower, in favor of the generalized thought that some oils, "perform very well"...?? Sorry, by what criteria do you conclude that an oil performs very well?...

If you followed the thread, you would know that Jim didn't rule out "good enough oil performance" from a large portion of the tested oils for use in stock applications. I took away from the test that his goal was to compare oil performance by measuring the pressure and temperature at oil failure so he could have better oil choices for engines which have higher than normal stress at the cam/follower interface. I wouldn't dissmiss his scientific test results in favor of a less scientific "to each his own beliefs" generalization. I do think he showed something significant about choices of oil... because of the science........ . . .
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No, I am suspect of bench tests.This is not to say his tests are without merit..A true test would be a dozen engines running in real life conditions for an extended period.How do oil perform when contaminated by conbustion products and fuel that are present in any engine oil. Yes, it would take months and be very expensive......So many engines running different brands of oil and more often than not the end result is the same..You cannot say that any particular oil is better than another in the real world, from actual on the road back to back road testing? Or can you?
 
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My point would be that if you are testing oils for film strength and lubricity, the test did that. Whether you, I, or anyone else thinks the result of the testing translates to a meaningful correlation in the choice of oil and it's potential to resist cam to follower wear, I don't see how you can question some amount of correlation from testing to real engine results.

Sure 5 norton engines running side by side with different oils could be more of a single variable style test, but maybe one of their cams wasn't hardened properly so that it fails prematurely. Are we really going to get a pure single variable test being that there will be some variables in all engine builds? Maybe one oil pump has a little more pressure than another. Maybe there are some other differences that effect wear even in the optimum test situation.

I like science. Give me a better reason than "his test isn't perfect" to dismiss his ideas and conclusions. Maybe there are reasons that I'm not aware of, or some other consideration not mentioned. Ultimately, I beleive there's probably a difference in the quality of different brands of oils... If there wasn't, then they should test similarly, which they don't seem to do...
 
A lot of you are aware that the testing I did was originally just to satisfy my own curiosity. But then when I showed people what I was doing it blew up into a fairly complex test with oils coming in from all over the world.
Between the testing I did and the conversations I had with a lot of oil professionals -I learned a lot.

And as Hillbilly has pointed out there are a lot of things that may not be covered in my testing.

So what I did was gave the results of the testing I did and I tried to not make too many recommendations.

The one thing I did learn and can recommednd is if high temperatures are a concern with your ambient conditions or engine tune or use, then low heat from friction is very important.

Where-as if you are running a drag racer with extreme spring pressures then the heat from friction makes little difference but the oil needs to be able to handle high loads.

The recommendations I have made were for oils that I have had good experiences with over the years. So that is not to say these are the only oils that work or even the best for the application -but they have worked for me. Jim
 
Fast Eddie said:
Jim’s summary of Silkolene Pro 4 20w50 was “Medium load capacity along with high heat would not make it a good choice for a Norton”.

I used it previously until one day at Mallory Park, after a days riding on new oil the oil pressure warning light came on on my BSA R3 powered bike. Much doom and gloom engulfed me as I pondered (another) hideously costly engine rebuild.

Loooong story short... it was the oil. It had overheated and broken down to the point that it couldn’t even provide enough pressure to keep the oil light off. Goodness knows what would have happened if I’d have kept riding it with that degraded / broken down oil in it.

Jim’s test bench conclusion and my own empirical evidence seem to corroborate each other completely.

It’s probably great in a modern water cooled engine, but I’ll not be putting any in any of my old bangers again.
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So I was referring to the non synthetic oil, and if I was thrashing a bike on a racetrack I would want the best oil, absolutely agree with you there. Just saying for running around the highways and byeways of this green and pleasant land basic dyno oil probably is good enough. Just change it regularly. End of the day it is just down to the individual, just my thoughts for what it is worth. I think Hillbilly has made some good (devils advocate) points.
 
Hillbilly Bike said:
There's been a lot of disussions about "scar tests" on auto racing forums...Many well experienced builders dismiss it as have no relevence to operating conditions inside the engine...And many lower rated "scar test" oils perform very well in actual running engines...
To each his own beliefs...
Click to expand...


Auto racing is not classic air cooled motorcycles in the real world and performed well in actual running engines means what based on what ?
You can pull any statement to pieces.

The bottom line is there are very few people on the planet who will get off their ar$e and actually do some form of test in the private sector, that test might be conclusive, it might not.
It might answer some questions, it might lead to others, just remember there are more people today due to the internet that believe the earth is flat.

Based on the JC testing (US$50 well spent for me) at least I have some good information for my oil choices and am thankful for that.
 
I for one appreciate reading findings from an individual actually getting up off of their ass and doing some first hand research into the matter, or I'd never have questioned running the same old oil which came in my Norton 46 years ago in the belief of a solution to preserve the powerplant for a more lengthy period. The change may help or it may not, but at the very least there has been an awakening from complacency & status quo acceptance of original recommendation by the manufacturer.

I'm going along the lines of Norton riders more so than snake oil makers when making decisions on my machine.... I'd drive over a cliff with a few of you before following behind a salesman or lawyer on a safer road.
 
I'm the guy who sent in the Amsoil for testing. I was very disappointed that my precious 15w-50 Amsoil Racing Oil did not get top honors. It came in #20 on the load bearing scale and fell down on the heat from friction. On top of that, the Amsoil lacks the anti corrosion additives so putting the bike up for winter presents a problem. I chose the Royal Purple HPS 20w-50 because of the combination of load capacity and low heat from friction. I also like the fact that it attained it's rank with no additives.

I have now run 1500 miles on one oil change and am up to 1000 miles on my next change with this oil. I can say that it performs better than the Amsoil in that the pressure stays up better at idle when the engine is hot. I had one run up from Durham, NC to Baltimore Maryland on a mild day where my oil pressure stayed 42psi at 75 mph mile after mile. Then I had my hottest blast ever on the bike coming out of Atlanta on Thursday before the Barber Vintage Festival where the ambient temp was just over 100 degrees. I stopped to make sure the liner was out of my summer jacket. (it was) but the bike did fine with oil pressure staying over 35 psi at between 75 and 80 mph. (22t front sprocket so RPM reads between 3800 and 4200 at those speeds.)

My other anecdotal evidence for Jim's testing is concerning the miserable failure of Aero Shell. I have friends in aviation who have been complaining about cam failures for years running that oil. I know that they cannot just put in Royal Purple HPS but I wish they could.
 
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Given the choice between spending my hard earned money on the best oil available for my machine or a cheap oil and a hamburger... I'm going with the best oil.
 
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