Have you been able to determine the difference in the new Mobile 1 and the old stuff? I don't see that you are testing both...I saw the new stuff you're talking about in Wally World the other day and thought about this post.

Mac

 

Mac, I have an analysis of the old Mobil 1 15w-50 red cap auto oil. Here it is compared to the old V-Twin 20w-50:


Oil Brand Mobil
Oil Blend M1 V-Twin Red Cap Auto
Visc Label 20w-50 15w-50
Ag 0 0
Al 2 0
B 195 176
Ba 0 0
Ca 2540 2339
Cr 0 0
Cu 0 0
Fe 2 2
K 0 0
Mg 16 18
Mn 0 0
Mo 79 69
Na 6 8
Ni 0 0
P 1282 1072
Pb 0 0
Si 6 8
Sn 0 0
Ti 0 0
Zn 1613 1175

Flash points of both were above 430 degrees F.

Boron, phosphorus and zinc are anti-wear additives. Magnesium and calcium are acid neutralizers. Boron also acts as an acid neutralizer. Molybdenum is a friction modifier; too much of it and you get the slipping clutch if you use it in the primary. (I've been told the new yellow cap 15w-50 auto has about 100 ppm of molybdenum, still not enough to cause clutch slippage in an HD.)

These versions show some differences, in favor of the V-Twin. But to my thinking, the slightly increased amounts of the additives do not justify the huge increase in price.

One claimed difference that doesn't show in a chemical analysis is the composition of the base stock. The V-Twin version is supposed to utilize a base stock whose molecules do not shear as easily. Therefore, if you choose to use the same oil in the engine and transmission, the V-Twin would definitely be the better choice. If you decide to stick with gear oil in the tranny, then very little is gained by favoring the V-Twin over the red cap in your engine. And the synthetic gear oil made by Mobil 1 has even better shear characteristics than the V-Twin 20w-50.

Just to confuse the issue further, here is another comparison of the V-Twin vs the red cap:

Phos Zinc Boron Magnes Calcium
Mobil V-Twin 1,084 1,377 176 499 1,561

Mobil 1 SH 1,095 1,427 169 553 1,714

In these analyses, the red cap auto oil is superior to the V-Twin version. Note, however the oils are apparently older versions, as the red cap is "SH", and the present standard is "SL", if I remember correctly.

I know all this mumbo-jumbo bores the crap outta some folks, but some of us tech-nerds get off on it. After all, I spend my days measuring the differences in pressure caused by chopping a beam of infrared light as it shines through a tube of stack gases in order to determine the CO2 content. Oh, and measuring the amount of NOx in the gases by its chemiluminescence. (Are we having fun, yet?)

 

TILT!

I'm not totally sure what I'm looking at...numbers on the left are VTWIN? No...those are the old brand Mobile?

I'm wondering if you are going to test that new Mobile 1 stuff that is supposed to be good for 15K miles...

You also drew some conclusions on gear oil and regular oil, but I'm not seeing where from these numbers you were able to do that...

Mac

 

That's Greek to me for sure.

I'm sure glad Skip can put this in laymen's terms.

Please?

 

Skip,

As I look at it again, I have a better understanding of what you were showing me...just needed to look at it again. Those numbers are from anothe analysis that you did earlier, right?

My question becomes this:

There are increased levels of Boron, Calcium, Molybdenum, Phosphorus, and Zinc in the VTWIN stuff as I read your post. But, without a real understanding of how much is a lot...I don't know that this means anything to a layman. The way I see it, the increase is by

Boron - 10%
Calcium - 8.5 %
Molybdenum - 14.5%
Phosphorus - 19.5%
Zinc - 37%

Magnesium 25% decrease

What are these things doing for or against me?

Mac

 

Man, I shoulda previewed that before posting it. Too late in the pm for me to be thinking straight!

As you noted the V-Twin has higher levels of most additives. I already summarized the purpose of the additives so I won't repeat that here. The additive amounts in both these oils is quite a bit higher than in "regular" oil, if there is such a thing anymore.

Here's a chart that compares some other oils:

Brand Phosphor. Zinc Boron Magnesium Calcium

Cstrl GTX 928 1,133 0 259 1,163

Golden Spectro 1,587 1,548 132 842 320

Gulf Super Duty 1,007 1,116 88 923 898

Mobil 1 SJ 1,058 1,348 163 521 1,717

Mobil 1 SH 1,095 1,427 169 553 1,714

Mobil V-Twin 1,084 1,377 176 499 1,561

Mobil 1 EC 835 955 100 1,497 820

Pennzoil GT 665 951 77 678 652

Valvo Race 707 936 90 522 1,546

Valvo Prem Blue 954 1,019 85 479 875

This shows a much wider additive difference among the oils. Notice the M1 V-Twin and M1 SH are nearly identical. They differ from the newer M1 oils in that respect.

Let's compare the M1 SH and the Castro GTX, a very good non-synthetic oil. Anti-wear: Notice the levels of phos & zinc aren't all that different, but the GTX has no boron. Acid control: GTX has significantly less magnesium, somewhat less calcium, and no boron. So the chemical conclusion is: Mobil 1 will need to be changed less often (has more acid neutralizers); if a severe oil starvation problem occurs, the M1 will offer greater "last resort" protection (more anti-wear additives); the M1 will stand up to high engine temps better (synthetics have much higher flash point).

When you compare the GTX against the Penzoil and Valvoline, the GTX fares pretty well.

Back to the original M1 car vs M1 V-Twin analyses: The bike version has a better additive package. It is reputed to withstand shear better than the car version. Whether the differences are great enough to justify the nearly double cost is up to you. From the manufacturers' strictly financial standpoint, there is no way the bike version costs that much more per quart. From a rider's standpoint it might be a different story.

My conclusion: If you use the oil only in your engine, save your money and use the car version. If you use it in your transmission, go with the bike oil.

On the gear oil issue: Confusion reigns! The gear oil we call "75-90 weight" is nearly identical in viscosity (what we call weight) to 15w- or 20w-50 motor oil. It's measured using a different standard, so comparing them by the weight numbers becomes an apple - orange thing. And because they are nearly identical in viscosity, HD probably modified its Syn 3 20w-50 for so it would suffer less shear, and be able to be used in a tranny.

Here's some info comparing Mobil 1 car oil against some good motorcycle oils. It has to do with viscosity retention, and for a bike motor is probably more important than the additives we looked at above.

Relative Viscosity Retention
(as a percentage of initial viscosity retained after normal use in the same motorcycle)

0 miles 800mi 1500mi
Mobil 1 Car 100% 86.6% 83.0%
Castrol Syntec 100% 78.1% 74.5%
Castrol GTX 100% 72.2% 68.0%
Honda HP4 100% 69.2% 65.6%
Spectro 4 100% 68.0% 63.9%

The Honda HP4 & the Spectro 4 are motorcycle oils. Notice they performed worse in viscosity retention than the car oils. Also, the Mobil 1 and the Castrol Syntec are synthetic, the Honda oil

 

Yeah, the Mobil 1 I bought is the newest version with the gold-colored cap.

 

Sittin here reading this thread a thought occured to me "The xtra additives dont equate to the dbl the price" (I think thats what I read) ....... Could the price be reflective of production, specificaly lower? Everybody and their brother uses M-1 in their cars so they produce more.

I am not opposed to saving a little ca$h on oil but would not want to have availability be an issue. Seems from what Ive read we might be paying a premium for the availabilty

 

Thanks, Skip...

Any thoughts on the wet clutch? I'm still not sure where we are on that, or why we think the car stuff is tooooo slippery for that....

I'm kind of coming around to Mobile 1 for me...but not sure why I wouldn't want it in all 3 holes. The dealer is telling me to put the HD "synthetic" stuff in all three holes...and the 20W50 at that!

Mac

 

Yeah, I'm sure the production numbers have something to do with the price. As far as availability, there are a lot more places that sell Mobil than HD oil - Wal Mart, Auto Zone, ABC Auto Parts.

Just saw my local NAPA store is selling Royal Purple oil. That's some good stuff, but I didn't check on the price.