Not looking to start a brand debate here. I just have a question.

about to do my 1000 mile fluid change.

obviously I'll use synthetic 20w-50 for the engine.

Either amsoil or redline tranny fluid, or Mobil 1 75w-90 gear oil.

what I don't completely understand is the requirements for the primary.

could someone explain what I should be putting in the primary?

thanks

 

Same thing your owners manual says. Formula +

 

And I don't think you'll like the 75W-90 in your trans. It gets a little thin when it's hot. Better to go 75W-140.

 

The primary contains the clutch - don't just put any oil there is my opinion.

Ideally, use a motorcycle oil that is JASO MA/MA2 certified. JASO is a Japanese standard that is very strict concerning motorcycle clutches.

If you trust Harley, use their primary fluid. Amsoil also makes a JASO primary fluid at the same cost as Harley.

Personally, I'm a "change often" guy, so I use Mobile1 Racing 4T 10w40 which is JASO MA/MA2 certified. I'ts $10/quart at walmart, but Mobile1 routinely does rebates which will lower the price down to ~$7.50/quart which is half the price of Harley and Amsoil...at the half the price, you can change 2x as often and your primary will love you for that

 

I would suggest using HD Formula Plus in trans and primary until your certain you will not have any trans fluid migration into the primary.JMHO

 

I'm with GTK I recommend HD Formula plus as a precautionary measure. By 5k or maybe sooner you will know if you have any migration issues. Not all trans fluid compatible with wet clutch. I like to use dino for first 5k in motor also. Just my opinion gives it better chance for things to seat up

 

And I'll be the third to agree with GTK.

Use Formula+ in the trans and primary until you can confirm that you don't have any oil transfer going on.

 

its been 7 months fellas. Little late to advising this guy now

 

Yeah, but for anybody else out there that has this same question, I'll have to agree that using Formula+ until you're sure you don't have a transfer problem is the best policy.

 

Plain ol' H-D dino in the motor - changed every 2500-3000 miles, Redline in the tranny, and Formula+ in the primary is the winning combo for me.

Other's opinions will surely vary!