sunruh,
Can you expand on the 8:1 winter blend or point me to a source that has more information on this?
Ethan
Can you expand on the 8:1 winter blend or point me to a source that has more information on this?
Ethan
The amount of viscosty improvers that have to go into the base oil is primarily a function of the spread between the top and bottom number not the ration of the top number to the bottom number. Both 5W40 and 15W50 have a 35 point spread so the quantoty of viscosity improvers needed should be about the same.quote:
Originally posted by sunruh:
i'm not good at writing, so if anybody wants to expand on this, please do so.
5w is 1/8th of the 40wt. 8:1 ratio.
10w30 would be 3:1, 20w50 is 2.5:1 and so on.
don't ask about 0wXX. it violates the rules.
what it mainly shows is how many viscosity improvers have to go into the base to get this vast a range. lower the ratio, not as many.
basically, they have their cake (40wt), but want to eat it in the winter too (5w). these long chain oil molecules are what gets chewed to bits and show up as shearing (ie viscosity loss).
people on here have *claimed* that various oils are either more shear stable or even "unshearable" only to be proven totally wrong inside the workings of actually motorcycles (nicrfe1370 - street and myself - dirt and countless others).
in my 4.75 years of oil analysis on my bike (same lab, same bike) i have been able to prove that the entire population has been greatly mislead, ill informed or downright lied to when it comes to oil in a motorcycle with regards to the oils longevity due to shearing. that while some oils might be marginally better than others, after a few miles, it really doesn't matter anymore. out of my 15 analysis, only 2 oils didn't shear out of grade in use.
yes, these are some pretty strong words, but my analysis speak for themselves. bitog has shown that my findings are not unique either.
Sunruh, after reviewing you comments in this thread it looks like one of these oils is Rotella 15W40 - is this correct? What is the other oil that did not shear?quote:
Originally posted by sunruh:
... out of my 15 analysis, only 2 oils didn't shear out of grade in use. ...