Oil grade question?

firefly

firefly

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Been using 10-40 mobile T4 synthetic & really like it but I use the bike daily in stop & go traffic for work, (home health) so I am going from one address to the other all day long year round, a lot of short but spirited trips.
is it better to use 20-40 instead for more protection?
Thanks
 
all the numbers mean is viscosity at a certain temperature the lower the number lower the temp and vice versa so infact 10w 40 is better than 20w-40 for you in this regard. however since your in la its not going to mean much since you dont get too cold.
this is at least how i under stand it if i am wrong please correct me.
 
I can't see you having anything to be worried about; you're using the right weight and a quality oil. Maybe change your oil more frequently if it bugs you
 
Oil

I have tried mobile 1 royal purple maxima amzoil and I am now running Lucas semi synthetic 10 40. I love the Lucas is by far the best I have tried shifting is noticeably smoother and engine noise is quieter at low rpm
 
Dustin said:
I can't see you having anything to be worried about; you're using the right weight and a quality oil. Maybe change your oil more frequently if it bugs you
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Agree. Seems you are overly hyper on maintaining. You are using what the engine was designed for. Don't try to second guess the engineers.

Being an engineer myself, I will explain try to simplify oils and viscosities. The viscosity numbers for the oils work like this:
Think of oil as honey. At low temperatures honey doesn't flow very well (say you got it out of the refrigerator). It can be assigned a viscosity number - and that number doesn't change.
But when you heat it up the honey flows more easily. It still has its same assigned viscosity number. But as a fluid's temp is raised, it flows more easily - we all have seen that.

Characteristic viscosity is assigned numbers ---- and they are well defined by science.

10w is light weight - low viscosity - it flows easily at lower temperatures
20w is not as light a weight - it is a heavier, higher viscosity than 10W - it doesn't flow as easy at low temp.
30w is even heavier (higher) viscosity - flows even less readily at lower temps (but at higher temps these higher viscosity fluids flow more easily than they do at low temps - just like heating the cold honey -as it warms, it pours more easily from the container)
40w is even heavier weight viscosity- it doesn't flow well at cold temps at all but as it warms up, it too, starts flowing more easily.
50w
60w ... on and on.

Oils
In the earlier days there were only straight weight oils. Straight weight means the oil has only one viscosity characteristic assigned to it. It behaves like all other fluids. Knowing the viscosity number for the oil, you know how it will pour at 30 degrees F and also at 100 degrees F and also at 900 degrees F. All that is known - because you know the viscosity of the fluid (oil is a fluid).

In early engines, all that was available was straight weights - single viscosity oils. So the engineers had to comprise in their engine design work. The oil needed to flow some at low temps so that the oil pumps could move it around the engine for lubrication. But as the oil heated (engine machine parts have very high temps in normal operation (like 1800 degrees F)). So as this oil is heated to these high temps it starts to flow very easily - and can flow too easily - becomes too thin (like water) and it will not hold the film thickness between critical mating metal surfaces (the oil pumps try to maintain this film through pressure - but if the fluid (oil) becomes too thin the film thickness becomes too thin and the metal parts begin to make direct contact -- VERY Bad!!!)
So the engineers have to chose one oil - with one viscosity that will flow enough at cold temp(metal temp - and cold here is a relative thing - cold with respect to the upper high temp - 800 degrees - so as you can see, 50 degrees is a cold temp compare to 800 degrees)
So they choose one oil that will allow enough flow at cold temp (so that the pump can pressurize the lubrication system and provide the film thickness required to keep the metal parts from making direct contact with each other (and causing damage)) But the oil also has to have enough thickness (viscosity) at the high temps to allow proper film thickness,

This is a real balancing act. But that is what the early engineers had to work with.

But along come more modern times. And the modern chemists figure out a way to provide additives to an oil that will give that one oil two different viscosity properties! It's like magic! Those good ol' chemists!

What results is a whole series of oils that are called "multi-grade" oils - because they have multiple grades of viscosity all in one oil.
They work like this:
At cold temps (remember - this is relative) the oil has one viscosity number - say X. But at high temps (the temps of the working engine after it has been fully warmed up) the viscosity changes to Y. (It doesn't change suddenly - like the flipping of a switch at a certain temp - but rather it changes its viscosity gradually until it reaches thaT engine design upper temperature - when the oil now has the higher viscosity, Y). Those chemists are so clever.

The oil in this example would be labeled Xw-Y.

So the oils you are dealing with are 10w-40 ---- meaning at cold temps (relative, remember) the oil acts and flows like a straight weight 10 weight oil. And at high temps (engine upper design temp - near 800 degree F) the oil acts and flows like a straight weight 40 weight oil.

And that is it. You now know all the stuff.

So you should be able to figure out for yourself what you should do.

What you should do is do what the engineers have told you to do - because they designed this engine to operate with that oil with those specific viscosities. And the design oil is given in the owners manual. Now if weather temperatures change enough that the engineers know that there is a benefit to changing the viscosity, then that will be given in the owners manual along with the viscosity and conditions where the change applies.

If a person takes it upon themselves to use some other viscosities - then they are changing the film thicknesses and pressures that are trying to separate the metal parts within the engine. If the oil and pump has enough tolerance and leeway, they may be OK. But they are tampering with a critical design characteristic of the engine.

If you change to 20w-40, when you start the engine (it is relative cold), the oil will flow at a 20 weight rate. It will be stiffer, heavier (cold honey, remember) - the pump won't be able to pump it as easily as the engineers wanted it to be when the engine was cold. Is this what you want??? For the oil not to flow as well when the engine is cold?

I have known very few people who have knowledge of this. If viscosities are changed, then to keep the design consistent and safe, the oil pressure regulator should be changed also - including, perhaps the pump.
But why would you want to do that - why would you want to change the viscosity??? Most people who do change - don't have any idea what they are doing - what they are affecting. It's just by the grace of the engineers over-engineering their designs and the oils having somewhat overlapping characteristics that the engines are able to survive. But in some cases, changing the viscosities will shorten the life of the engine. The oil lubrication system will not be working in the perfectly balanced way that it was designed to. This is a complex subject and I have attempted to give a very brief, simple (and therefore incomplete) description.
 
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Agree with all Lindy said plus it might make your engine quieter (for a while) to use heavier viscosity but is it really doing its job?
 
Thanks to all who have responded, I'll stick with 10wt- 40 and just change it at 3K instead of 5K. my use is more than severe on this bike & I just want to keep it humming.
I just love this bike, it fits all my needs perfectly.
 
W means winter. It's the viscosity at 0c, the other number is the viscosity at 100c. (frozing point / boiling point)

If you live in a hot area, the first number doesn't apply. And even if you do, once your engine is warm, it doesn't change anything.

Yamaha recommends 10w40, stick with it!
 
So, I'm at a loss. I have a Gen II Fz1. It did not come with the owner's manual. When I went and did the first oil change the always helpful shop-man said that if I wanted best performance to go with a full synthetic Yamalube 15w-50.

Should I be running the 10w-40 Yamalube mineral oil (which is the mineral oil, rather than the full synthetic 15w-50 or 10w-30race/semi-syn 10w-50)?

What should I do?
 
Ssky0078 said:
So, I'm at a loss. I have a Gen II Fz1. It did not come with the owner's manual. When I went and did the first oil change the always helpful shop-man said that if I wanted best performance to go with a full synthetic Yamalube 15w-50.

Should I be running the 10w-40 Yamalube mineral oil (which is the mineral oil, rather than the full synthetic 15w-50 or 10w-30race/semi-syn 10w-50)?

What should I do?
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If it does`nt get below 0c were you live, it`s fine,check the book when you down load it,what grade you use will also depend in what climate you live
 
Ssky0078 said:
So, I'm at a loss. I have a Gen II Fz1. It did not come with the owner's manual. When I went and did the first oil change the always helpful shop-man said that if I wanted best performance to go with a full synthetic Yamalube 15w-50.

Should I be running the 10w-40 Yamalube mineral oil (which is the mineral oil, rather than the full synthetic 15w-50 or 10w-30race/semi-syn 10w-50)?

What should I do?
Click to expand...

Just go to Walmart and pick up a gallon of Shell Rotella T6 Full Synthetic (JASO rated) for about $21. Far cheaper than other synthetic oils and works just as well. Many people here use the Rotella T6 oil with excellent results.
 
adamsrcworld said:
I have tried mobile 1 royal purple maxima amzoil and I am now running Lucas semi synthetic 10 40. I love the Lucas is by far the best I have tried shifting is noticeably smoother and engine noise is quieter at low rpm
Click to expand...

I almost bought some lucas synthetic the other day but in the end stuck with the Mobil 1 4MT 10-40......

Maybe I will try it out on the next oil change.
 
loosenut said:
#1. You can download the owners manual for free (http://www.yamaha-motor.com/assets/service/manuals/2008/lit-11626-21-51_fz1_1455.pdf)
#2. As long as the oil meets the requirments from Yamaha, it is fine to use.
#3. :poke::stirpot:
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fisherman322 said:
If it does`nt get below 0c were you live, it`s fine,check the book when you down load it,what grade you use will also depend in what climate you live
Click to expand...

View attachment 13282

Interesting that it puts in two different choices 10w30 and 20w-40.

So, in theory the 15w-50 should be sufficient for the temp here in AZ. It gets down to just about freezing (36-38) and has highs of (115-120) in the summer.

After reading lindy's detailed engineering explanation for choosing oil I was concerned about there being insufficient protection and the whole maintaining pressure in the oil pump thing was concerning.
 
From specificatons [8-2] Aussie handbook

View attachment 13285



Ssky0078 said:
View attachment 13282

Interesting that it puts in two different choices 10w30 and 20w-40.

So, in theory the 15w-50 should be sufficient for the temp here in AZ. It gets down to just about freezing (36-38) and has highs of (115-120) in the summer.

After reading lindy's detailed engineering explanation for choosing oil I was concerned about there being insufficient protection and the whole maintaining pressure in the oil pump thing was concerning.
Click to expand...
 
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