Just tried this oil after trying many other brands and it's about as good as it gets. My local HD dealer carries it. See the full story here. http://www.hdtimeline.com/oil_related_tips/1238-oil_suggestions_for_harleys.html#post5426
It works well in the 6 speed, the IDS system took care of all the noises in the trans and this oil made it even smoother than it was with the M 1 that I was using. I have used the redline also in the past and I think this has it beat. It just seems so much smoother and I'm not an easy sell on anything. It's 75/140 but it seems as if the clutch plate drag associated with the other 75/90 or the 75/140 Mobil 1 is eliminated. Shifts smoother and with less of a clunk. Neutral is a snap now too as compared to the M 1
Glider..Have you ever used Royal Purple?....i tryed a few and found it to be very good...in the Transmission I'm speakin of..
I have never used RP but the guy who told me about this oil had used it and he switched to Spectro too so I was going by his recommendation and based on the oils that I have used in the past which have been many , I feel this is the best so far.