Originally Posted By: Brian553
Dang.
Alarmguy, I have a number of questions to your statements:
1. Will the oil actually stabilize in a shared sump? I want to say I have seen a few UOAs that show they just keep shearing all the way to a 20-weight
2. Does a GrII HDEO have the same shear performance as GrIII motorcycle oils?
40/15 = 2.7 but high VI GrII some shear resistant VII
40/10 = 4 GrIII with some shear resistant VII
I assume the basestock isn't a concern when it comes to shearing, but the VIIs are.
To answer question #1,
I doubt anyone can show me a 15/40, 20/50 or Mystik 15/50 oil that sheared down to a 20 weight, with reasonable mileage of 5000 miles, in a motorcycle.
A 15/40 or 20/50 will hold up better then 10/40 and will blow any oil such as Rotella 5/40 out of the water as far as holding close to its viscosity.
No secret I use Mystik 15/50 semi syn as its the only decent priced HDEO (c-rated) oil in the 50 range on the market in the USA. I posted many UOAs and a VOA over the years. My bike maker suggests an HDEO as a substitute if I cant use their brand (of course they say switch it out once you can buy their brand) but their oil is also formulated like an HDEO and ironically made by the same maker, Citgo.
Im happy with this oil, no secret there.
If I had the option to use an API "S" rated instead of "C" I would without question mostly likely choose a 20/50 conventional but then again, now that I know the Mystik, most likely would stay with it..
I am not really brand loyal, just give me the proper API in the recommended weight. I dont buy all the marketing garbage of oil companies unless the FULL set of results are shared with the public and they never are.
To answer #2,
I cant answer your question, I have no idea what you are talking about, I am no expert nor does the subject interest me (see the sentence above this one), all the oil talk, make up of oils, what oils are used, ect mean nothing to me because those numbers do not mean the superior looking oil on paper will produce less wear then the nasty looking one, in fact, the nasty looking oil may produce less wear as many conventional oil produce the same and in many cases less wear then synthetic oils. If they have the same API they all meet the same requirements of the engine maker.
I buy the oils for my vechicles with the proper API and weight range, though I normally step it up if possible, like wifes car requires 5/20 or 0/20 I use 5/30. Im in the south.
Before anyone here starts flaming me that im crazy and their synthetic oil is superior to ya da ya da. I am NOT knocking synthetic oils, I am saying, if you change your oil ON TIME, there is a pretty good darn chance the conventional oil will be just as good, if not better at preventing wear.
If you do NOT change your oil on time then a synthetic will be more stable, hold up better and not produce sludge as much as a conventional, in most cases, however that still does not mean you will have less wear. But if your an abuser, synthetic for sure.
) not the price of the oil...
