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Author Topic: 2 quick oil questions  (Read 1381 times)

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Offline DrM

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Re: 2 quick oil questions
« Reply #30 on: July 01, 2020, 12:14:33 am »
Give it up lunkman.  I don't need to justify anything to you, and you have no argument worth listening to. And insulting me just makes you look infantile.

Offline lunkhead

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Re: 2 quick oil questions
« Reply #31 on: July 01, 2020, 12:28:42 am »
Just curious what your goal was. Sorry to rattle your cage.
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Offline Sdaniels

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Re: 2 quick oil questions
« Reply #32 on: July 01, 2020, 09:38:16 am »
So I did some looking around & found a few places with people discussing mixing different weights of oil.  They were trying to get middle ground between the grades or get an oil with broader range from cold/hot running temps...mixing 0W40 with 10W50 would yield something like 5W45.  Someone even went so far as to get 3 different grades between 6 quarts, did the math to come up with a 10W35 average.  But someone points out to just pickup 10W30 because their is no real difference between 30 & 35 weights, especially when using different brands.  So when DrM says he mixes 20W50 & 15W50, what does that accomplish?  17W50?  Hardly seems worth the effort or that it will accomplish anything.  Oil viscosity decreases with use.  You start with 10W40 but end up with something lower by the the time it gets changed.  Synthetic oils don't break down as much as conventional but they do break down some.  I disagree with DrM when he says Lunkhead has no argument worth listening to.  I find most of Lunkhead's discussions extremely enlightening & this thread is no different.  I might have considered DrM's position if he had stated he simply disagreed with Lunkhead but to claim nothing he stated was worth listening to?  C'mon now, that's just arrogant trash-talk that anybody can see through.  Almost sounds like DrM is compensating for something...I mean, you never know.  People can say anything on the internet...I'm a doctor, a rocket scientist, an engineer, Superman.  Who knows  :o 8)
« Last Edit: July 01, 2020, 12:58:49 pm by Sdaniels »
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Offline DrM

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Re: 2 quick oil questions
« Reply #33 on: July 01, 2020, 04:49:54 pm »
Oh, look! It is the bloviating blokes - Junkman, and Baby Danny.  Finding meaning in nothing!  Bloviate away, boys, bloviate away.   

Offline lunkhead

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Re: 2 quick oil questions
« Reply #34 on: July 01, 2020, 10:06:29 pm »
What causes the second number in a multi-grade conventional oil to change is more easily explained and unlike mixing two different viscosity base stocks which changes the QUALITY of the base stock, it changes the QUANTITY instead. It simply has to do with how much VI improver (the crap that expands when heated) is added. The physical difference between a 10w-30 and a 10w-50 is that more of the additive is used to slow the flow of the -50 more at operating temperatures. So, for all practical purposes, mixing a -30 and -50 to make a -40 is no different than an unmixed off-the-shelf -40.

The improver has no lubrication properties so a mono-grade with no VI improver contains the highest percentage of oil molecules possible. For any given quantity, a multi-grade like 10w-30 will provide better lubricition than a 10w-50 because of the higher oil content. That's why you should always pick a conventional multi-grade with the least difference between the two numbers for the ambient temperature range in which it'll be operating. The VI improver is also the main source of sludge and deposits when you let the oil go too long and deplete the detergents and what not. Synthetics don't have those problems because they have very little additive if any.
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Offline DrM

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Re: 2 quick oil questions
« Reply #35 on: July 01, 2020, 10:13:09 pm »
What causes the second number in a multi-grade conventional oil to change is more easily explained and unlike mixing two different viscosity base stocks which changes the QUALITY of the base stock, it changes the QUANTITY instead. It simply has to do with how much VI improver (the crap that expands when heated) is added. The physical difference between a 10w-30 and a 10w-50 is that more of the additive is used to slow the flow of the -50 more at operating temperatures. So, for all practical purposes, mixing a -30 and -50 to make a -40 is no different than an unmixed off-the-shelf -40.

The improver has no lubrication properties so a mono-grade with no VI improver contains the highest percentage of oil molecules possible. For any given quantity, a multi-grade like 10w-30 will provide better lubricition than a 10w-50 because of the higher oil content. That's why you should always pick a conventional multi-grade with the least difference between the two numbers for the ambient temperature range in which it'll be operating. The VI improver is also the main source of sludge and deposits when you let the oil go too long and deplete the detergents and what not. Synthetics don't have those problems because they have very little additive if any.
Very good bloviation -- sounds intelligent, uses lots of words, and means nothing.  You should go into politics.

Offline lunkhead

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Re: 2 quick oil questions
« Reply #36 on: July 01, 2020, 11:10:27 pm »
I remember back when we first started selling synthetic motorcycle specific oil, it was only good for racing. It didn't meet the demands of a street bike so we were stuck with semi-synthetic or conventional oil. The semi-synthetic was the way used to blend in an additive package containing the missing ingredients like corrosion inhibitors and detergents or whatever. Those were desperate times. I was happier than a pig in shit when they came out with the synthetics we have now.
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Offline Sdaniels

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Re: 2 quick oil questions
« Reply #37 on: July 02, 2020, 09:14:28 am »
What causes the second number in a multi-grade conventional oil to change is more easily explained and unlike mixing two different viscosity base stocks which changes the QUALITY of the base stock, it changes the QUANTITY instead. It simply has to do with how much VI improver (the crap that expands when heated) is added. The physical difference between a 10w-30 and a 10w-50 is that more of the additive is used to slow the flow of the -50 more at operating temperatures. So, for all practical purposes, mixing a -30 and -50 to make a -40 is no different than an unmixed off-the-shelf -40.

The improver has no lubrication properties so a mono-grade with no VI improver contains the highest percentage of oil molecules possible. For any given quantity, a multi-grade like 10w-30 will provide better lubricition than a 10w-50 because of the higher oil content. That's why you should always pick a conventional multi-grade with the least difference between the two numbers for the ambient temperature range in which it'll be operating. The VI improver is also the main source of sludge and deposits when you let the oil go too long and deplete the detergents and what not. Synthetics don't have those problems because they have very little additive if any.

Lunkhead, service manual shows a chart with oil grades to use for given temperatures.  Goes from 10W30 up to 20W50.  Any issue with using 5W40?  I typically change my oil every six months because I don't ride much, about 2500 miles or so in a 6 month period.  Doing that I will be riding through summer & winter months on the same oil.  I changed oil at 600 miles, put in Rotella T4, conventional oil but it only comes in 15W40.  I plan on putting T6 synthetic which comes in 5W40 when it's due for the next oil change.
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Offline lunkhead

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Re: 2 quick oil questions
« Reply #38 on: July 02, 2020, 11:13:33 am »
Sdaniels, the Rotella is probably the most universal oil there is. It passes just about every standard out there. The JASO MA is the only standard we need to look for so it's fine. The wide viscosity range in a synthetic isn't due all the crap necessary for a conventional multi-grade oil so what I said about conventional oil doesn't really apply.

https://www.rymax-lubricants.com/blog/what-does-the-jaso-oil-specification-mean/

« Last Edit: July 02, 2020, 11:17:49 am by lunkhead »
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