rear diff oil ?

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I understand that it's wise to preheat this gear oil (microwave or stovetop) before pouring it into the hole.

Pouring cold lubricant on your gears can cause them to shrink,

and never again properly mesh.

(On straight-cut gears, it's especially critical, ...I think.)

Seriously. :drag:

 
I understand that it's wise to preheat this gear oil (microwave or stovetop) before pouring it into the hole.
True: Happiness is warm oil.

MamaYama put an oil warmer (coolant-to-engine oil heat exchanger) on the FJR engine for just that purpose.

In the '50s the Germans were top competitors in Grand Prix m/c racing. Before N.S.U. put their class-winning 'RennMax' on the starting grid the mechanics would have the oil drained and heat it on a stove and install 'hot' oil just before the race. The British, looking-on, laughed at those silly 'Jerries'. When the flag fell, the N.S.U.s were half-way round the course while the Brits were still letting internal friction warm the engine's lube oil.

 
Yammie Whale Jizz is the Shitz!

WhaleJizz.jpg


 
what kind of differental oil are you guys using ? Yamaha dealer dosent carry yamalube or whatever the book calls for..
cant be much different than what honda or bmw use is it?

how about mobil 1 synthetic? what weight do you think the Yamaha oil is ?

You are about to be repremanded, and given a "link" to answer your question, but before that hapens: ( I'm the nice one here )

I use Mobil 1 synthetic 75w90

Have a nice day, and log out before you get offended by the next guy.

Too late, they're here
+1 on the Mobil 1 Syn 75w90

 
I dont see a problem with the guestion at all. I enjoyed reading the replys. If theres a post that bothers someone they should ignore it and just move on.

 
It needs to be GL5 80/90
Nope, GL4 80W is the Yamaha spec. GL5 can damage some types of bronze bushings over time due to the sulpher (EP)content I believe. Many folks say " I've been using (pick your favorite) gear oil for X miles now and I've had no troubles". GL5 may be OK, but unless a diff is removed dissembled and methodically measured for tolerances and wear who knows if GL5 is OK. It (GL5) predominantly was a problem in older manual gearboxes that specified a gear oil that existed before the widely available GL5 oil. Folks changed to GL5 and the syncros would be damaged and prematurely wear out.

Yes, I know there are no syncros in a diff. My point is that there are bronze type bushings in the diff, Yamaha specs GL4, Why they do not spec the improved and widely available GL5 is not known to me. You can make an argument that they do this to sell their gear oil. You can also argue that they specify GL4 for an engineering reason based upon the materials used in the diff. Knowing that you have this bit of factual information, you decide what to do with it.

From Redline whitepaper:

Most manufacturers of manual transmissions and

transaxles recommend an 80W or 90W GL-4 lubricant.

GL-5 gears oils which are required in hypoid differentials

are not used in most synchromesh transmissions

because the chemicals used to provide the extreme

pressure protection can be corrosive to synchronizers,

which are commonly made of brass or bronze. Typically,

the use of a GL-5 lubricant in a synchromesh

transmission will shorten the synchronizer life by one

half. The extreme pressure requirements of spur gears

and helical gears found in transmissions are not nearly

as great as found in rear-wheel drive differentials. A

GL-4 lubricant provides adequate protection for most

manual transmissions, unless a unique design

consideration requires the extra protection of a GL-5.

 
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I understand that it's wise to preheat this gear oil (microwave or stovetop) before pouring it into the hole.Pouring cold lubricant on your gears can cause them to shrink,

and never again properly mesh.

(On straight-cut gears, it's especially critical, ...I think.)

Seriously. :drag:

I could see pre-heating the gear oil for a racing application. But for a street bike the need to pre-heat seems unwarranted. Using your logic wouldn't the ring and pinion gear set also shrink and never mesh properly when the ambient temp is in the 30's here in Maine? Or are you saying to pre-heat the gear oil when you add it to a HOT ring and pinion gear set? If so even then I highly doubt that any damage would result from adding gear oil which is at ambient temps to a HOT Diff. All the bike manufacturers make their products to survive almost any kind of neglect and misuse and they don't recommend pre-heating the gear oil. Plus like I said the Diff gear set can go from 30 degree temps to VERY HOT temps in a short time and I've never heard of any problems? Does this make any sense or am I misinformed?

 
I dont see a problem with the guestion at all. I enjoyed reading the replys. If theres a post that bothers someone they should ignore it and just move on.

I have to agree, why would someone open a thread they have no interest in, read it and then tell you you should do a search rather than just moving on to some thread they do have a interest in? just a jerk I guess.

Anyway, I work for a manufacturer and there are many reasons to stick with the recommended lubricates and OEM parts. I believe in it without question. If nothing else it makes no sense to me to spend $10K on a bike and then try to save $5 on engine oil or diff oil in this case.

 
God, these are great. Use good gear oil. Period. It's two gears meshing in there.Don't use engine oil. It's still too light.

Use gear oil. Exact viscosity is totally irrelavant.

This is even easier than engine oil. In the engine, don't use "Energy Conserving." Anything else goes. In the drive, use gear oil. If it says gear oil, it's for gears. The final drive has gears. That'll work.
Actually..., the viscosities of, say, SAE 40 motor oil and, say, SAE 80 gear oil are very similar (about the same -- different measuring scales...).

(engines have gears, too)

It's all about the (extreme pressure) additives in gear oil (much, much more) to help protect the, sliding, hypoid gear teeth and rear-drive load pressures..

 
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I use Mobil 1 75-140 Syn gear oil and change with every oil change

 
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Murple syrup, Grade B is the best. :p

Seriously! My dealer doesn't carry the specked out type for the feeej. When i asked he didn't even know they made special gear oil for the FJR1300. Anyway i just buy the shit on the shelf they recommended and change it every time I do an oil change. GL4 somethin or other.

 
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Anyway, I work for a manufacturer and there are many reasons to stick with the recommended lubricates and OEM parts. I believe in it without question. If nothing else it makes no sense to me to spend $10K on a bike and then try to save $5 on engine oil or diff oil in this case.
As has been stated, availability is the biggest issue.

Yeah, you can order it from a Yamaha dealer and shlep back and forth to the dealership picking it up after it comes in (because they don't have the whale jizz in stock), or you can order it online and pay an extra $10 in shipping the little pint of liquid gold. Or you can just use the same gear oil that you probably already have on the shelf from all of your other vehicles. The choice is all yours.

Nobody has ever reported a final drive failure on an FJR attributable to using an incorrect lubricant. Many factory authorized Yamaha repair shops just use the standard Yamaha Gear oil, (ie not the 9079E-SH001-00 whale jizz), because that is what they have on hand.

Yamaha is banking on there being a number of people that will follow their recommendations explicitly. That's how they have the nerve to charge >$20 for a pint of the stuff when you can buy twice as much of any other fully synthetic gear oil for half the price, and they quite intentionally do not put any specs anywhere in writing as to what is actually in the bottle.

Does anyone actually believe it costs them that much more to make it (actually get it bottled for them)?

 
I'm a Mobil 1 fan boy myself. But IMO it doesn't really matter what you use as long as it meets the design spec. If I have a gearbox it pretty much takes Mobil 1 75-90. If I have an engine it takes whatever weight is specified in the manual in Mobil flavor.

My Saturn Ion Redline calls for GM spec GM4718M for it's motor oil (same as the Corvette). FYI even Wal-Mart Full Syn oil (made by Warren oils) meets that spec. The way I see some engineers somewhere that get paid WAY more than me figured this stuff out and as long as I use an oil that meets the Spec and change it at the recommend intervals I'm good to go :) The rest such as brand choice is just that a choice made by the individual.

 
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