my clutch has never been smoother than it is with atf, I have a local shop that helps me with stuff I don't think I can do and he has used atf for years, I was a little skeptical at first but I like it

 

Not on mine you can't!

 

20w 50w v line 4 stroke dino in all 3 holes... change engine every 2 to 3...

 

Mobil 1 synthetic ATF.

ATF is a waste of money? I blew $22k on a motorcycle that is used strictly for fun.

 

10w40. Pretty sure that was standard before HD syn3 and all these "chaincase/primary" specialty products. I use Amsoil motorcycle synthetic; obviously opinions vary re synthetic or conventional but what I would NOT do is run standard automotive synthetics as I was given to understand they can cause issues with wet clutches while motorcycle synthetics should not. For conventional oil I would run a diesel version for same reason, though would likely be a 15w40 in that case. I would likewise avoid running "gear" oils in primary, 80w90 and such, as they have other additives designed for transmissions/differentials. I've also heard of heavy gear oils causing issues in older chain driven transfer cases on 4wd pickups that specified 10w40 engine oil, and while it seems unlikely to be a problem at temps we ride bikes I don't see the point risking it.