I've been testing Red Line vs. Amsoil in one of our Harley Drag Bikes, so far I can't tell any difference in the Primary or Trans. Both do excellent.
Have to admit I like being able to order Red Line on Amazon.

 

Good point.

I tried synthetic once. Only difference I noticed was a thinner wallet. Motor temp did not change. The 10K change interval was nice, but oil filters don't last this long. I went back to dino oil and haven't looked back.

 

I like and use the Redline V twin shockproof transmission fluid, because its a lot tacker then the recommended HD 20-50. I think it also shifts better too. When the Harley Dealer recommend it on the down low, I had to try it. I also got the Redline primary oil. No complaints here

 

know this real old thread but that’s funny but it might be because they’ve stripes those legs and *** with to many Redlines

 

For every Syn3 quart you use...God kills another kitten..

 

Why use Redline over other synthetics ? Because it is better oil ,which contain no impurities from being drilled from the ground. Don't believe it ? Get specifications and data sheets from independent research labs and compare synthetics to crude oils. There are different grades of synthetic oils. Redline and Spectro Platinum are two of the best. Two Harley dealers in my area carry both Spectro and Red Line along with Harley branded oil. The mechanics in both use Redline or Spectro in their machines. Been running both for years..