Follower scar oil tests (2018)

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Since Jim doesn't have a time machine, or does he?, I guess it is impossible to answer the question:
Would any of the oils available in the 60's and 70's be even marginally acceptable for Nortons based on Jim's current test criteria?
Please Jim, carry on. Did you receive the Motul 5100 I sent you?

Ed
 
APRRSV said:
Since Jim doesn't have a time machine, or does he?, I guess it is impossible to answer the question:
Would any of the oils available in the 60's and 70's be even marginally acceptable for Nortons based on Jim's current test criteria?
Please Jim, carry on. Did you receive the Motul 5100 I sent you?

Ed
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I am sure they would. The difference would be they would be straight weight oils, which were the only things that were any good at high temps from the 60s or 70s

And yes, I got the 5100. Jim
 
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I had posted earlier on the question of why modern car engines can regularly go 200K+ without a rebuild and whether modern oil is a factor. One factor is the more precise machining and micro finishing especially on bores and pistons. This requires the friction modifiers in SN oil so really the two work together. I'm doing some research on the subject to see if it can shed some light on Commando problems.
The other big factor appears to be fuel injection and modern computer controlled ignition systems that allow much less carbon build up in the oil due to unburnt gas.
We know an AMAL carb has 5 different ways of controlling fuel flow depending on throttle position and how hard it is to get each one perfect. Also Commando engines wear their rings and bores a lot faster than modern car engines so there is more blowby sooner.
My 78 Bonneville has 23K miles on it. Compression is still 145psi and it has new Premier carbs that I have spent a lot of time trying to dial in. I just changed the oil at 1000 miles and it was a real dirty black. So obviously I have some blowby and maybe a circuit or two is too rich. Probably not an uncommon occurrence on old Brit bikes.
What I struggle with is do I use a relatively cheap oil say Valvolene 4 stroke dino motorcycle oil and change it frequently to get rid of the contamination or do I pay 4x the cost for something like Royal Purple and leave it in longer.
I know Jim does long distances on his bikes and looks like he rebuilds them fairly frequently so wear might not be a big factor. But there are also a lot of these bikes that are worn but not to the point of rebuilding.
 
htown16 said:
I had posted earlier on the question of why modern car engines can regularly go 200K+ without a rebuild and whether modern oil is a factor. One factor is the more precise machining and micro finishing especially on bores and pistons. This requires the friction modifiers in SN oil so really the two work together. I'm doing some research on the subject to see if it can shed some light on Commando problems.
The other big factor appears to be fuel injection and modern computer controlled ignition systems that allow much less carbon build up in the oil due to unburnt gas.
We know an AMAL carb has 5 different ways of controlling fuel flow depending on throttle position and how hard it is to get each one perfect. Also Commando engines wear their rings and bores a lot faster than modern car engines so there is more blowby sooner.
My 78 Bonneville has 23K miles on it. Compression is still 145psi and it has new Premier carbs that I have spent a lot of time trying to dial in. I just changed the oil at 1000 miles and it was a real dirty black. So obviously I have some blowby and maybe a circuit or two is too rich. Probably not an uncommon occurrence on old Brit bikes.
What I struggle with is do I use a relatively cheap oil say Valvolene 4 stroke dino motorcycle oil and change it frequently to get rid of the contamination or do I pay 4x the cost for something like Royal Purple and leave it in longer.
I know Jim does long distances on his bikes and looks like he rebuilds them fairly frequently so wear might not be a big factor. But there are also a lot of these bikes that are worn but not to the point of rebuilding.
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I do prefer to freshen up the head every 20 to 30 thousand to keep it running strong, but I would like to see 70 or 80 thousand from the lower end and pistons. I have done it before and hopefully the next build will do it again.
 
And I found I have 30 good arbor races, 40 bad arbor races and 30 more on backorder.
So at least I can proceed with the testing and it sounds like they will replace the soft races.
 
Hey, some good news is better than no good news!

I'm hanging on this thread to see how my Castrol V-Twin 4T comes out under the new regimen.
That GTX with the good results: Is it labeled as motorcycle oil?
 
I used Castrol GTX back in the day. At that time it was just "oil," not "motorcycle oil." Of course, maybe, as some have suggested, the engine was on the verge of exploding every day for the five years I owned/raced it! Fortunately, it never did! :)
 
Tighter tolerances and micro finishing have caused some major auto manufacturers some real headaches in recent years since the 80's and 90's. Once the super finished polished surface was considered the best, most probably still is. If the oil can't film or the part can't retain a film as they found out, it much like using no oil at all. This lead to rethink and specific manufacturer oils along with surface modifying packages in the oil.

I have pictures of a cam and big end shells that have covered over 20K on Tesco own brand full synthetic 5W-40 oil that was dead cheap, other than a soft piece of crap in one shell set which did not break the outer layer, the coating is untouched. The cam was damaged but this I believe was due to debris from when I changed the head as it after that change noticed pick up the drain plug.

I have now switched over to Millers Classic Sport 20w-50 semi-synthetic, but this ran far hotter in 30 Deg heat recently than the Tesco oil which was 5W-40, I might give the Millers Classic Sport High Performance 20W-50 a try, if it is any good stick with it if not back to the Tesco's so I can thrash the bike in January from start up, yes I am really that kind to my bike.
 
MexicoMike said:
I used Castrol GTX back in the day. At that time it was just "oil," not "motorcycle oil." Of course, maybe, as some have suggested, the engine was on the verge of exploding every day for the five years I owned/raced it! Fortunately, it never did! :)
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I see Castrol GTX is still available. You are still free to use it, tests notwithstanding. As others are free to take advantage of the oil testing Jim Comstock is doing and use a better performing oil than Castrol GTX.
 
The Castrol GTX is car oil. And it is damn tough.

If you change it often and don't mind the extra heat, it will definitely provide the protection.

It might even be a good choice if you live in a cooler climate or tend to make short trips. The extra heat will help keep the moisture level down.
 
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"If you change it often and don't mind the extra heat, it will definitely provide the protection."

Maybe I'll go back to using it in the Norton; I always liked the name! :)
 
MexicoMike said:
"If you change it often and don't mind the extra heat, it will definitely provide the protection."

Maybe I'll go back to using it in the Norton; I always liked the name! :)
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I’ll use a more scientific approach when it comes to choosing an oil. Like test data, as opposed to an oil's name..
 
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Mr. Rick said:
Hey, some good news is better than no good news!

I'm hanging on this thread to see how my Castrol V-Twin 4T comes out under the new regimen.
That GTX with the good results: Is it labeled as motorcycle oil?
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Mr. Rick: How did you choose this Castrol oil as opposed to the other Castrol Motorcycle oil? Just curious.
 
JimC said:
I’ll use a more scientific approach when it comes to choosing an oil. Like test data, as opposed to an oil's name..
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Well, I was young then and I just picked the coolest-sounding name of the oils listed in the Norton owners manual.

What oil test data have you been using all these years to select oil for your various vehicles?
 
Follower scar oil tests (2018)


I ran this for 30,000 miles. Has it been tested?

https://www.amsoil.com/shop/by-product/motor-oil/racing/dominator-sae-60-racing-oil/?code=RD60QT-EA
 
MexicoMike said:
Well, I was young then and I just picked the coolest-sounding name of the oils listed in the Norton owners manual.

What oil test data have you been using all these years to select oil for your various vehicles?
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NCOC test, 1993. Prior to that, personal testimony.

You said you would choose Castro’s GTX TODAY simply because of it’s name.
 
Fast Eddie said:
I’m gonna go out on a limb here Jim... but I think he may have been joking...
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I’m aware. The issue, as I see it, Mike has little or no regard for the results of the oil testing being done. Facts be damned, so to speak. Much like the global warming deniers.
 
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