[Bilgemaster]

Yeah, I know...Oh great: another motor oil thread. But I'm standing here in Wallyworld looking at this Quicksilver stuff I'd never noticed before. It's strange, 'cause it has no round API service symbol displayed anywhere on it. Still, Quicksilver (i.e., Mercury Marine) is usually tip-top quality goop. I'm currently running a cocktail of Mobil1 15W-50 synthetic with about a cup of Marvel Mystery Oil and about 2 ounces of that Lucas Break-in Oil Additive TB-Zinc Plus for the extra shot of zinc for the tappets (as per recommendation in another thread) in my 2005 "Iron Belly". I'm just wondering if I should give this Quicksilver stuff a second look when the time comes for the next change. There just doesn't seem to be much at all in the Forum Archives about it.

[longstrokeclassic]

Quicksilver is another name for Mercury, so my guess it’s somebody else’s oil with an inhouse label stuck on the bottle.  I use Fusch silkolene in my EFI mainly because my nearest bike place stocks it but because it comes with all the recommended specs for the bike. Any modern multi grade has got to be better than the straight grades and whatever else was available when your engine was originally designed if of course it meets the applicable specs it requires.

[Bilgemaster]

Apart from portisheadric's kind comments, this thread's been a peaceable home for the crickets, hasn't it? Serves me right for firing up any sort of engine oil thread, I suppose. 

How a cricketeering cricket might appear

Still, a recent thread amongst those young UCE rapscallions concerning some questionable new User Manual recommendations about changing the oil in 2018 Euro4-compliant bikes still being broken in at 300 and then only again at 4,000 miles (that's not a typo) got me to thinking again about my own forthcoming oil change and what might be the optimal goop for my "iron belly". Please understand that I am no chemist nor do I hold any particular expertise in lubrication technologies--I'm just some guy looking for the best readily-available reasonably-priced goop to keep his Enfield most happily thumping along without mail ordering exotic ointments or the rarest Essence of Unicorn Burp from Narnia. I'm kinda just thinking aloud here, and if my ramblings help anyone else out down the road even in the least, so much the better

It turns out that getting details on the actual specifications of that Quicksilver 20W-50 Full Synthetic Motorcycle Oil I'd spotted in the local Wallyworld at $28.62/gal., in particular its zinc additive compounds (i.e., ZDDP, moderately higher concentrations of which are said in these forums to be especially helpful for cushioning our Iron Cylinders' rattly old style flat tappets, cam followers and so forth), turns out to be fairly difficult. It's tricky enough that just a few years ago a kindhearted user named "ericj205" over on the Bobistheoilguy forum had a fresh sample of the stuff privately lab tested for everyone's benefit, are here's a screenshot I've archived on one of my own little web domains of the results (the original image is being hosted by Photobucket, so there's no telling when those ratbastards may make another ransom demand or just "disappear it". Those who've ever had their pix on forums like this held for ransom will share my loathing of Photophuckit and applaud my caution in squirrelling it away elsewhere):

Cutting to the chase, looking at the Additives section results above we see that Zinc measured 1136 parts per million (PPM) and Phosphorous 943. Sifting through a search of these very Forums for terms like "zinc" or "ZDDP" seems to reveal a consensus by folks like "Ace.Cafe," who always seems to know what the hell he's talking about, that ZDDP "over 1000 is OK" or "1100 or maybe a bit more" might be optimal particularly for the guts of our old "iron bellies," if not necessarily for those "different as chalk and cheese" UCEs. So, if I understand these numbers correctly, that Quicksilver might do the trick well enough. Still, the lack of an API certification might be a cause for concern (It is with me), and there is no guarantee that that spot lab test done a few years ago might accurately reflect its current formulation.

Meanwhile, at the other end of that Wallyworld aisle, you've got your various Mobil 1 products. Of the ones perhaps most suitable SAE-weightwise for Enfields are Mobil 1™ 15W-50 ($22.88/5-quart jug or $7.88/quart) and Mobil 1™ V-Twin 20W-50 ($9.54/quart [no larger size]). Fortunately the very basic specs for the whole line of Mobil 1 products is readily available in a simple PDF chart found here. Cutting to the chase, the two most suitable for Enfields viscosity-wise work out as follows:

Mobil 1™ 15W-50
Nominal Phosphorous Level, PPM: 1200
Nominal Zinc Level, PPM: 1300
Product Description: Boosted, higher viscosity, advanced full synthetic formula designed for performance vehicles.
Recommended Consumer Applications: For high HT/HS (i.e., High temperature, high shear) applications. Racing and Flat tappet applications.
API, ILSAC, and Other Industry Approvals:SN
A3/B3

Mobil 1™ V-Twin 20W-50
Nominal Phosphorous Leve1, PPM: 1600
Nominal Zinc Level, PPM: 1750
Product Description: Advanced full synthetic formula designed specifically for motorcycles where clutch lubrication is also important.
Recommended Consumer Applications: All motorcycles where 20W-50 is specified, especially V-Twin engines.
API, ILSAC, and Other Industry Approvals: SJ

Given the fact that the jug price of the regular 15W50 works out to less than half per quart of the 20W50 special motorcycle stuff, seems to have sufficient zinc at 1,300 PPM (a tad higher once I've added a 2 ounce dash of that Lucas Break-in Oil Additive TB-Zinc Plus, as per recommendation on these Forums, and of which I've still got plenty left for several oil changes to come), I think for now I might stick with my current cocktail of regular Mobil1 15W50, with about a cup of Marvel Mystery Oil, an ounce or two of that Lucas stuff, and a fresh filter each oil change.

This is not to say that I wouldn't grab a quart of that 20W50 V-Twin brew on the road if I were running low on my own  brew and wanted its extra dash of zinc . Also, I suspect that it may be far more suitable (JASO rated?) for those with UCE engines who need to be concerned about their unit construction's primary drive and clutch and gearbox all sharing the same type of oil as the engine. But my primary's full of Type F ATF, while my separate 5-speed gearbox has AMSOil straight GL-4 90EP synthetic gear oil in it.

[Arizoni]

Mobil 1™ V-Twin 20W-50
Nominal Phosphorous Leve1, PPM: 1600
Nominal Zinc Level, PPM: 1750
Product Description: Advanced full synthetic formula designed specifically for motorcycles where clutch lubrication is also important.
Recommended Consumer Applications: All motorcycles where 20W-50 is specified, especially V-Twin engines.
API, ILSAC, and Other Industry Approvals: SJ

I have used this in my RE since it was new, including during the initial break in period and it's never caused a problem but I think the part of the quote I added the bold faced type to is interesting.

One of the few things about Mobil 1® V-Twin 20w-50 oil that is a little odd is it does not meet the requirements of JASO MA or any of the JASO requirements.  At least, the label doesn't say anything about meeting them.
For an oil that is "designed specifically for motorcycles where clutch lubrication is also important" I would think the JASO requirements would be high on the list of priorities.

For those who don't know, the JASO standards were developed to test the compatibility of the oil with wet plate clutches.  It basically makes sure the oil does not cause the clutch plates to slip.

I've never had a clutch slip problem so I will continue to use V-Twin but I wonder why they don't list JASO MA on the label?

[longstrokeclassic]

The original SJ spec mineral oil with additives needed to withstand the unique stresses placed on it whilst working in a flat tappet environment wouldn't meet all of the totally different lubrication needs of a high revving multi cylinder Japanese motorcycle. This is why the Japanese came up with their own oil specification.   

Mobil have gone to the trouble of creating a totally synthetic chemical formulation (that's still lovingly referred to as oil) specifically designed to mimic the properties of the original SJ mineral oil.
Seems a bit of a win/win combination if you own an iron barrel engine.