Learn something new everyday. My concern would be proper cooling and flushing of the wet plate clutch combined with (possible) drag. Judging from the comments these seem to be groundless.

 

[quote 418

Learn something new everyday. My concern would be proper cooling and flushing of the wet plate clutch combined with (possible) drag. Judging from the comments these seem to be groundless.end quote]

As chains are in every modern auto transmission, it just makes sense to use ATF in the HD primary-- same components in there. I don't see drag as a problem at all having used it for several years in both Evo's.

Type F fluid has no friction modifiers and hooks up hard--some bike drag racers use it.

Dexron II has a bit of friction modifier in it, but I am yet to hear a complaint about Dexron II or III slipping. I use DIII in the FLHT and have no issues, but I don't ride it hard.
Just my choices.
V2

 

....................

 

Dan 89,
re "first time I dropped it in gear I noticed something strange...No clunk. I used Dexron type" - gee, how would I know it's in gear without the clunk??? I dunno, man, I think I'll miss all those Harley clunks and whirrs and such.

Seriously, thanks for the info//

 

Cooling is accomplished by oil splashing on the primary covers which are blown with air.There likely would be not difference in temps regardless of which primary fluid is chosen. Thinner fluids generally react to cooling effect more than thicker ones since the film is thinner.
Ron