Gear Oil

[shiftMX]

I know some guys who use automobile transmission oil instead of specific oil made for dirt bikes. He says he has been using it a long time in all of his bikes and never has a problem. His friend uses expensive oil in his Kawi and he has been burning clutches. They do ride hard, so it's not like they baby the bikes.

I would like to know what you guys think about this matter. What kind of gear oil do you use? Also while I am thinking about it...does anyone use higher octane pump gas or race gas to mix. And what brands of oils do you mix with your gas for the 2-strokes?

[cowboyona426]

I run Mobil 1 15-50 red cap engine oil in my 426. It is the only Mobil 1 oil you should run in your bike if you choose to use Mobil 1 because it doesn't have any friction modifiers (good for cars, but bad for bikes- they make the clutch slip). Oil choice is as much a personal preference as the bike you ride, find something you like that works for you and go with it. I only like to use the best stuff on my bike, so that's why I went with Mobil 1 15-50. One word of caution- if you go to a synthetic oil, you can't go back to dino oil. As for premix- back when I rode a pinger, I mixed on quart of Yamalube with 5 gallons of pump gas.

[Woody_YZF]

I've never heard of such a thing as running car transmission oil, but I can tell you that they are different. I don't know that I would dare run regular tranny oil in my bike. If you do, let us know. I'm curious how it will turn out.

[Yardpro393]

i ran mercron dextron atf in all my bikes for years with no problems. Jeremy Mcgraths mechanic listed it as one of thier "tricks" several years ago.

here's why i think it works well.

in an auto trans, the bearings spin at a much higher rpm, there are gears(planetary gears) that spin with a much higher load than those in a bike. and there is a friction clutch ( the clutch bands) that is lubed by it that is a similar material to the clutch in the bikes. If atf works fine in a suburban towing a 30' boat it should work fine in your bike.

[Woody_YZF]

Originally posted by yardpro
i ran mercron dextron atf in all my bikes for years with no problems. Jeremy Mcgraths mechanic listed it as one of thier "tricks" several years ago.

here's why i think it works well.

in an auto trans, the bearings spin at a much higher rpm, there are gears(planetary gears) that spin with a much higher load than those in a bike. and there is a friction clutch ( the clutch bands) that is lubed by it that is a similar material to the clutch in the bikes. If atf works fine in a suburban towing a 30' boat it should work fine in your bike.

That's interesting to know.... and it makes sense.

[cowboyona426]

Thanks for the info yardpro, I think this post should go to the KB now.

[Yardpro393]

yea, the knowledge base is a good place, cuase my knowledge is VERY basic.:

[Woody_393]

Originally posted by cowboyona426
IOne word of caution- if you go to a synthetic oil, you can't go back to dino oil.

What are you talking about? You can go back. Syn and dino oils are compatible with one another. Unless their is some un-written rule I don't know about. Everything I have ever read, says it doesn't matter. I don't know why it would???

Any insight you want to pass on to us?

[cowboyona426]

This is all based on what I was told when switching by the TT guys- but they told me that if you go from dino to syn, it's ok. BUT- when you go back to dino from syn, you'll start having problems with leaking gaskets. Might not be true, but I do remember hearing that.

[Woody_393]

Hmmm, no offense, but I don't buy it.

The syn is a little thinner, so going from syn to dyno wouldn't cause the leaks. It would be the other way around if anything.

[cowboyona426]

No offense taken. Like I said, it could be complete garbage. I don't know why you'd want to go from syn to dino anyways, unless it was an emergency situation.

[Woody_393]

Don't know why you would either. But shouldn't be a problem if you do need to or decide that all that money for syn is not worth it.

[Yardpro393]

here's how that rumor got started.

when synthetics first hit the market they were uncompatibale with the conventional oils. they would emulsify to a point and loose tier lubricating ability.
ALL the synthetics now have compatibility agents to let them mix. now they also have semi synthetics. that are a mix of both.

[Woody_393]

Thanks Yardpro, this has been moved.

[Florida 393]

If they were incompatiable the Bel-Ray, Yamalube, Maxima, Castrol and others are in trouble because they sell semi-synthetic oils. These are mixes of both in a specific ratio and with additives such as emulsification stabilizers and bike specific lubricating agents.

I use the Yamalube 4-R lubricant since it is the factory recommended oil and I get great results. You can change with the current oils and the gasket materials that are out there. The seals are a much higher quality material than the old dry rot prone types. The bikes now are light years ahead of the stuff we rode in the 70's.

Oils are strictly a personal choice. The ATF trick is used a lot and for some bikes it seems to run great. You have to think about what you are doing and be heads up about your ride's internals. This topic starts some fierce battles on web sites due to loyalties and personal experience. Use you head and make your own choices.

Regards,
Bill

[FXKX250]

I can't really speak from experience w/ the current crop of bikes (just picked up a '99 KX250 after a long absence from the dirt), but in 1972 Kawasaki actually specified ATF for their
Enduros (like my li'l F7).

[Jaybird]

If you are going to try an ATF, use Type F.
This type of ATF was desined for use in older version Ford transmissions. These types of trannys are similar to the action a bike clutch has.

The crap about synthetics and friction modifiers blows my mind.
Folks have been fed such loads of crap concerning these issues.

You see a guy looking for oil and truning around the bottle looking to see if the label has the "Energy Conserving" rating.
This is the same guy who will speak up on message boards steering folks clear of energy conserving oils and friction modifiers.
And why do they do this? Because they have no idea what they are talking about and simply pass on the dis-information as if it were fact.

Some facts...(take em or leave em):

Oils listed as "Energy Conserving" are not void of friction modifiers. In fact, most likely they DO contain frinction modifiers and viscocity improvers.

Reports of clutch slip are rare...and most every instance can be attributed to a mechanical issue that isn't related to the choice of oil. (of course the oil gets blamed)

To prove my points with more specifics...
Mobil1 15w50 indeed contained friction modifiers including molybdenum, boron, phosphorus, and zinc.
Mobil1 MX4T (motorcycle specific oil) contains even higher amounts of all of these friction modifiers than the 15w50 did.

If you are buying high-priced, moto specific oils..you have fallen into the trap that the mfg's set for you. They want to sell you oil at three times the price, and have you convinced there is no other way to go. They love it when you pass on the disinformation as well.
You are being their fool and marketing stooge.

One fact you can also count on...in motorcycles, the frequnecy of change is more important than the choice of oil. Particle counts grow astronomicaly fast with our type of engines and clutches. Most all oils on the market will protect your engine and parts just fine for short periods of time, until the particle count rises too high. Then it doesn't matter what oil is in the sump.

[mtk]

I agree with Jaybird 100%.

I use Type F ATF in all my dirt bikes, because as he said, the service it was designed around is almost a dead-ringer for a dirt bike tranny. I also use Mobil 1 exclusively in all my pavement-based bikes, both street and road racing machinery.

Oh yeah, one note: oils labeled as "Energy Conserving" are more likely to have MORE friction modifiers than those that are not labeled as such. This depends on the viscosity grade of the oil and will vary within an oil brand, not just from company to company.

As for reports of clutch slip, Castrol Syntec is the only one I know of, personally, to cause it. I also know that the 5w50 version of said oil has lots of friction modifiers in it. That ain't a coincidence.

His moto-specific oil comments are also 100% spot-on, and for the record, I worked in the oil testing industry for 13 years.

[ossagp]

Clutches definitely like the F type if you are asking them for a more secure hookup. Automatic transimissions of other brands even gave crisper shifts on it (read that made your tires chirp). The TH350 and TH400's love it.

Other than the way it works on the clutches and engagement I dont see any difference in the way the Dexron's, Chrysler spec'd etc work on the other parts. Funny that most of the Dexron transmission oils carry allison auto ratings,,,cat auto trans ratings etc. so did many 15-40 motoroils, and to look at them (that includes watching them pour) you wouldnt think they were too much alike. (Cat of course was using the one oil concept for the last 40 years. one oil in everything).

[mtk]

Originally Posted by Jaybird

If Mobil1 15w50 indeed contained friction modifiers including molybdenum, boron, phosphorus, and zinc.

Just FYI, but phosphorus and zinc are NOT friction modifiers or even parts of friction modifier additives. These two elements are found primarily in the ZDDP additive, which is an anti-wear additive.

The moly element IS part of friction modifier addtives, if I recall correctly, but it's not a straight elemental addtive either, but rather a moly compound.