Mobil 1 20w-50 Question

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CCI

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After a fresh build on a Shovelhead I ran about 50 miles with regular oil, changed it, another 500 with regular oil, changed it, and then put in the Mobil 1 20w-50 made for V-Twins. Ended up being a weird year, and only put 400 miles on that last oil change.

I remember decades ago with regular oil there was a recommendation to change it at least annually no matter how low the miles because of acid build up.

Would this apply to synthetic as well, or do you suppose the Mobil 1 is still OK?
 
Originally Posted By: NormanBuntz
How does the oil know it's only a year old?


Don't keep us in suspense...whats the punchline?
 
There was only 1 candle on the oil can.
grin.gif
 
I’ve run it about 18months and it was still fine with more miles.

The official recommendation is still 1 year, but I wouldn’t dump 500 mile M1 V-Twin.
 
Having worked on so many Harleys, I'll tell you this:
The carburetor you are using affects oil life more than miles or date.
 
Originally Posted By: Linctex
Having worked on so many Harleys, I'll tell you this:
The carburetor you are using affects oil life more than miles or date.


Fuel dilution ?

Best wishes , :)
 
Blackstone's stand on oil is that usage effects oil not age. But if your dumping gas in the cyls, that's winding up in the oil, your oil will test out to be thinner then when you put it in. Down A grade or so doesn't seem to effect the motors much as far as UOA's go.,,,
 
Originally Posted By: WyrTwister
Originally Posted By: Linctex
Having worked on so many Harleys, I'll tell you this:
The carburetor you are using affects oil life more than miles or date.
Fuel dilution? Best wishes , :)


You got it.
S&S are the WORST.

A Keihin CV on my Shovel got me 55-56 MPG.
 
most all of todays "synthetics" are regular oil kinda, group III highly processed CRUDE oil. after the law revision in 1999 most everyone went group III once the present stocks were sold. Mobil makes PAO, Ester + lower group oils as well, possibly a few years later changes were made with Amsoil being the latest though some group iV + V may be blended in some products. i am in that situation now with 3 motorcycles barely ridden this summer, they all have 15-50 silkolene said to br group III with ester, thinking another year may be ok as few very short rides are done, usually 30 to 90 90 minute runs!!
 
Originally Posted By: benjy
most all of todays "synthetics" are regular oil kinda, group III highly processed CRUDE oil. after the law revision in 1999 most everyone went group III once the present stocks were sold. Mobil makes PAO, Ester + lower group oils as well, possibly a few years later changes were made with Amsoil being the latest though some group iV + V may be blended in some products. i am in that situation now with 3 motorcycles barely ridden this summer, they all have 15-50 silkolene said to br group III with ester, thinking another year may be ok as few very short rides are done, usually 30 to 90 90 minute runs!!

What law again was that which got changed in 1999? I keep asking but you never answer.
 
Originally Posted By: kschachn
Originally Posted By: benjy
most all of todays "synthetics" are regular oil kinda, group III highly processed CRUDE oil. after the law revision in 1999 most everyone went group III once the present stocks were sold. Mobil makes PAO, Ester + lower group oils as well, possibly a few years later changes were made with Amsoil being the latest though some group iV + V may be blended in some products. i am in that situation now with 3 motorcycles barely ridden this summer, they all have 15-50 silkolene said to br group III with ester, thinking another year may be ok as few very short rides are done, usually 30 to 90 90 minute runs!!

What law again was that which got changed in 1999? I keep asking but you never answer.


I am guessing they are referring to when the term "synthetic" was allowed to be applied to Grp III oils?
 
Originally Posted By: CCI
...

I remember decades ago with regular oil there was a recommendation to change it at least annually no matter how low the miles because of acid build up.

Would this apply to synthetic as well, or do you suppose the Mobil 1 is still OK?


Even today they recommend every year.

No doubt in my mind the Mobile synthetic oil is ok but for me personally, I would think I was doing better for my engine by buying $4.00 a quart Valvoline Motorcycle conventional oil and changing every year. I may be tempted to not change the filter if we are talking super low miles for the year.
 
What causes one carburetor to be worse of fuel dilution than another? Metering accuracy? Float reliability?

I think you're right, I'm running an old S&S B, and there's no mistaking the fuel dilution, you can smell it. I dumped the 20w-50 today and replaced it with straight 60, the motor always has seemed to do better on SAE 60 in hot weather anyhow, SAE 70 if it's over 100 degrees. I'll probably keep the B for a while, I get a consistent 49 to 51 mpg and the bike will break the back tire loose on dry pavement in 1st and 2nd gear, and it will launch in 2nd quite effectively.

Life is full of little trade-offs.
grin.gif


I've got another Shovel with the S&S Super E (Shorty), no problems with fuel dilution at all that I can tell, starts great, runs great, consistent +/- 48 mpg, not as strong as the one previously mentioned, but it pulls strong and is quite nice at highway speeds.
 
a search should find the dispute, castrol was selling + advertising their Syntec as "synthetic" + was not legal!!! big $$$$ steps in + after deliberation $$$$ it was ruled by the advertising council that group III highly refined CRUDE oil was "close enough" to be sold as synthetic!! mobil brought this forward as they were using group IV PAO a true synthesised synthetic oil costing more, so as time went on after about 1999 oil blenders were almost all using the cheaper group III oils. its said some PAO + Ester are sometimes blended in to meet a spec. so all "synthetic" oils can be either Group III-IV-or V base oils or any combination there of. only those using the group IV + or V oils generally tell you, + others even Amsoil quietly sell you "synthetics" blended as cheap as possible!!!
 
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