yeah, I guess the operative word that was used in the context here is "they"... so a Parts or Service person may recommend something, but I was just treating "they" meaning the manufacturer and what their documentation states .. the folks that designed, developed, tested, approved, produced and provide the warranty and documentation ..two completely different interpretations of the word

 

I use Gear Lube in the primary and transmission, BelRay products, the V-Twin Primary and Trans specific. In my opion, this is opion, not fact, I think it shifts better and clutch feel is better. Neutral is a little easier. The only issue you might have is if your tranny wants to identify as a primary or crankcase and just protests the use of tranny fluid.

 

I could be wrong but usually the clutch youre running dictates the primary fluid to use. Ive used ATF with Rivera and Barnett clutches and standard harley primary fluid with factory clutches. I always run the RedLine trans fluid but their primary fluid I felt was too "watery" and didnt like it.

 

Ok, how about the product label itself? Or doesn't it say what I am reading?

 

The trouble with this driveline kluge, found in no other power transmission train I can think of offhand, is there are two completely different types of machine elements in the same oil bath:

(1) roller bearings, chain rollers, clutches (ATF type comonents)

(2) sliding cam ("compensator") (Heavy gear oil)

You can make a case for either being the targeted component to lubricate properly at the expense of the other. Like I said, I tried Red Line Primary Oil @ 131 ft-lbs and the clutches squeaked when engaging. So I thought I'd try the other way with heavy gear oil then my build says oh don't do that the clutches will get too hot and drag.

And then the Dealer, and the MoCo product label say heavy gear oil is good.

So, all three mutually-exclusive statements cannot be true simultaneously. One, or all don't know what they're talking about. That's why I asked.

 

it's their most expensive formula for alternative specific use applications..it's never been a factory fill for any motorcycles they have ever produced, because it's not needed for the overwhelming vast majority of owners..and let's be real here, the MOCO added it also because the the multi viscosity popularity of aftermarket fluids, and don't think for a minute it never crossed their minds to get in on a piece of the $ profit pie

 

Excellent Point!

You have articulated and addressed the issues I considered when I was pondering the dilemma of, "What fluid should I run in my primary?"

I concluded there is no "Perfect Solution" or even an "optimum solution."

What's good for the compensator ramps and primary chain, may be cross purposes with the clutch plates!

This has been an interesting discussion, but it reminds me of discussion I had with colleagues long ago in a galaxy far away.

At some point you have to admit that you are debating about "Pole Vaulting over Fly Turds" when an 80% solution for either application might be the best you can get.

At that point, you can begin to question the MoCo's design but that has survived the test of time.

Personally, I have been running the HD 80w-140 Synthetic in the gear boxes and primaries on two different performance builds (160/150 HP/TQ.

That was my choice when the migration / transfer issues were identified as an issue on early M8s. My logic was to avoid cross contamination.

I have accumulated over 50K miles between the two bikes and have no complaints.

They both shift smoothly, including neutral to first when I put it in gear.

I think we should all run what we want to run and just realize there may not be an optimum solution!

 

The statement was it was not recommended for primary. The statement is wrong.

The topic is performance builds. Not factory fill.

If you can't stay on topic, open your own thread.

 

Hey, I'm agreeing with you!

As far as the "not recommended for primary" comment goes, the MoCo states the purpose of the product is for transmission and primary chain case, and even has a little picture of what looks like a primary chain case on the bottle.

If those are not MoCo's recommendations, then it is very strongly implied that it is at least approved for those applications.

 

No, that's Webb again - just rambling. I'm used to it by now.