Rear Drive Oil Additive or not if using Synthetic?

[Guest Barrett82]

Once and for all, Does it need to be added if using a GL-5 rated synthetic oil in the rear drive?

(Mobil 1 75/90)( 2003 V11)

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[Guest ratchethack]

No. GL-5 rated synthetics do not require moly additive in the rear drive. If you do a search, there are a few discussions on this.

[Mike Stewart]

I still use the moly with the GL-5 gear lube. I am a firm believer in the stuff.

 

It goes back a few years ago when I had a BMW R1100RSL, I had the first service preformed at the BMW dealer in which the trans fluid was changed to a full synthetic. The bike now had a problem getting stuck in fifth gear after riding 100 plus miles in hot weather. Took it back to the dealer a few times, even let them ride it home a few times and they could not find anything. I was very unhappy with BMW and when it came time for the 2nd service I took the bike to a different dealer. Now get this, the new dealer I had the bike at was also a Moto Guzzi dealer, they changed the trans fluid and replaced with good old dino 90 wt with the added moly additive. Guess what, the bike no longer would get stuck in 5th gear.

 

So while the synthetic oils do have better shear qualities, I wonder about how the stuff sticks to the internal parts for lubrication.

 

 

 

Mike

[Dan M]

I still use the moly with the GL-5 gear lube.  I am a firm believer in the stuff.

 

It goes back a few years ago when I had a BMW R1100RSL, I had the first service preformed at the BMW dealer in which the trans fluid was changed to a full synthetic.  The bike now had a problem getting stuck in fifth gear after riding 100 plus miles in hot weather.  Took it back to the dealer a few times, even let them ride it home a few times and they could not find anything.  I was very unhappy with BMW and when it came time for the 2nd service I took the bike to a different dealer.  Now get this, the new dealer I had the bike at was also a Moto Guzzi dealer, they changed the trans fluid and replaced with good old dino 90 wt with the added moly additive.  Guess what, the bike no longer would get stuck in 5th gear.

 

So while the synthetic oils do have better shear qualities, I wonder about how the stuff sticks to the internal parts for lubrication.

 

 

 

Mike

87916[/snapback]

 

That's interesting Mike. When I first got my MG I changed all of the fluids and put Spectro synthetic gear lube in the trans & differential. After a few hundred miles I was missing shifts everywhere. I changed to Redline heavy and it completely solved the missed shifts. I think that so far as protecting the gears & bearings is concerned, sythetic gear lube is fine. The extra slipperyness of the moly additive or whatever Redline contains makes the difference in shift action.

[Daniel Kalal]

...Once and for all, Does it need to be added if using a GL-5 rated synthetic oil in the rear drive?

 

Yes.

 

Sorry; there's no such thing as "once and for all" with this topic. Years ago the "ignition points vs Dyna" debate was the #1 issue to get into an argument over. That has long been replaced by "pro Moly vs con Moly". But, even putting aside the fact that Guzzi specifies it; it doesn't cost very much. Why the concern? It'll make you feel better when you add it.

[Guest ratchethack]

....even putting aside the fact that Guzzi specifies it; it doesn't cost very much.  Why the concern?  It'll make you feel better when you add it.

Guzzi specifies use of moly with dino gear lube in the bevel drive. I'd certainly use it if I were running dyno. Guzzi dosen't specify synthetic oils anywhere to my knowledge -- unless they started doing so recently? Not using dyno in y'er bevel drive? Well, I reckon y'er already off the reservation WRT factory recommendations. ....

 

GL-5 rated synthetics contain extreme pressure (EP) sulphur-phosphorous solid particle dispersion compounds. If you're adding molybdenum disulfide (moly) to GL-5 gear lube in the bevel drive, I doubt if it'd hurt anything, but from a coupla tech references I read years back (that I can't find now ) it'd be overkill.

 

If it makes you feel better, by all means take a shot every morning in a shot glass before you ride. Y'er sure to notice a difference...

[Daniel Kalal]

Next up: counter-steering!

 

(and after that a discussion on the difference between torque and horsepower)

[Ryland3210]

Guzzi specifies use of moly with dino gear lube in the bevel drive.  I'd certainly use it if I were running dyno.  Guzzi dosen't specify synthetic oils anywhere to my knowledge -- unless they started doing so recently?  Not using dyno in y'er bevel drive?  Well, I reckon y'er already off the reservation WRT factory recommendations. ....

 

GL-5 rated synthetics contain extreme pressure (EP) sulphur-phosphorous solid particle dispersion compounds.  If you're adding molybdenum disulfide (moly) to GL-5 gear lube in the bevel drive, I doubt if it'd hurt anything, but from a coupla tech references I read years back (that I can't find now ) it'd be overkill.

 

If it makes you feel better, by all means take a shot every morning in a shot glass before you ride.  Y'er sure to notice a difference...

87957[/snapback]

 

I'm curious why MG specs the moly additive for the rear, but not for the trans. My new Cafe Sport has 120 miles on it, and misses shifts if I'm lackadaisical. Never had that problem with my Norton and Hondas, so I'm surprised. Any comments on adding it to the trans?

[Daniel Kalal]

...MG specs the moly additive for the rear, but not for the trans.  Any comments on adding it to the trans?

 

There are no hypoid gears in the transmission*.

 

Actually, I've almost always used it in both the transmission and drive box (for both my Daytona and California). It's just as easy to mix up a single batch, and I always change the fluids in both at the same time. I have run without it in the transmission, but it shifts better with it in; so that's what I do.

 

If you don't see your bike ever reaching 50,000 or 100,000 miles, it probably doesn't really make any difference if you use it or not. If you want to see 300,000 miles, it'd be a good idea (overkill with lubrication is not a bad thing).

 

* edit: strictly, the Guzzi rear drive box is not Hypoid, either. But, close enough for our discussion purposes.

[Guest ratchethack]

I'm curious why MG specs the moly additive for the rear, but not for the trans.  My new Cafe Sport has 120 miles on it, and misses shifts if I'm lackadaisical.  Never had that problem with my Norton and Hondas, so I'm surprised.  Any comments on adding it to the trans?

Wot Dan said. Hypoid gearsets and conventional right-angle bevel gear sets like on y'er Guzzi experience extreme pressure boundary lubrication conditions that tend to wipe oil off gear teeth with a twisting action, (particularly hypoid gears) subjecting them to metal-to-metal contact. Moly is specified to prevent this -- when used with dyno gear lube. The straight-cut gears in y'er transmission and helical-cut gears in other transmissions don't have the same level of extreme pressure boundary lubrication requirement and simply don't need it -- even with dyno.

 

Y'er Guzzi won't ever shift as cleanly and positively as your Norton or Hondas. Think of it as a "feature" of the Guzzi , and be more deliberate with your shifts. May I suggest pay more attention to her, adapt to her, don't get sloppy or she'll let you know..., and she'll reward you for the effort with flawless shifts every time....

[Guest MikeC]

Well here it goes again. If using GL-5 Rated oil you don't need moly, will it hurt to add some, no...will it help, no.

 

Moly is an old world additiive that was first produced during the industrial revolution to protect the bearings and gears that were produced at that time using inferior metals. GL-5 rated oil contains modern additives that do the same thing.

 

Redline's additive if you can see it under a microscope look like balls.

[Ryland3210]

Well here it goes again.  If using GL-5 Rated oil you don't need moly, will it hurt to add some, no...will it help, no.

 

Moly is an old world additiive that was first produced during the industrial revolution to protect the bearings and gears that were produced at that time using inferior metals.  GL-5 rated oil contains modern additives that do the same thing.

 

Redline's additive if you can see it under a microscope look like balls.

88079[/snapback]

Thanks for all the replies. I learned a lot from all, and all have good points. Sounds like Moly additive belongs in the category of "cheap insurance". I'll add it to the trans next time I change the oil, and definitely to my Venture's final drive. Any of you have any comment on using it for engine oil?

[Guest ratchethack]

Uh, why? What're you trying to achieve, if I may ask?

 

It's neither designed for, nor specified for use with engine oil.

 

It's of no use in the transmission, either, per comments above...but at least it probably wouldn't hurt anything in a transmission. Again, it's appropriate only for extreme pressure gear cases (again, see above). Though some engine oil additives contain other forms of molybdenum compounds other than molybdenum disulfide, solid additives like molybdenum disulfide aren't used in engine oil. I don't know if it'd cause problems or what kind of problems may result, but can't imagine any possible benefit.... Can't say as I know of anyone who's ever tried it, nor anyone who'd ever have a valid or justifiable reason to try it, either....

[Guest golden goose]

Looks like a geologist is needed here. Molybdenum is a transition element, also referred to as a metalloid, like arsenic. The sheeit be seriously hard and has one of the highest melting points of any element.

 

But that misses the point.

 

We ain't talk'in about the element. We be talkin' about the compound. Molybdenum disulphide (we will call it moly, but it is produced as molybdenite). In its unadulterated state, moly be slicker than owl sheeit.

 

The primary producer of moly is the Climax mine in Climax, Colorado. Near Leadville.

 

Now, this stuff can be spread thin. And as the sulphide, very soft and thin.

 

Boundary layer territory.

 

Go ahead. Give it a power pulse. A big one. Make its day. Plating out between iron mating surfaces, the covalent bonds between molybdenum and sulphur give, but do not break. And therein lies the beauty of this ugly stuff. It plates out thin yet substantial.

 

Stress it.

 

It seems that is what it likes best. But heat is not that much a part of it. So motor oil is a push. Un-shared transmissions, and differentials, such as Guzzi's prefer, is moly territory Highest temps: no. Anything else: go for it.

 

Of the 92 naturally occurring elements, molybdenum is remarkable in terms of what it can do.

 

Use it wisely.

 

GG

[zoltan c]

Last time I was at my dealer I picked up all the lube and filters, Motul synthetic for the motor and trany and Moto Guzzi dino gearlube for the rear. My dealer never even mentioned adding moly. I haven't changed the rear drive oil yet, but I'll have to pick up some moly from the sound of it. Its a good thing that I read this forum! (I guess I could read the owner's manual )