i love this thread!!! everyone trying to convince everyone else why the oil they prefer is best!!!!
there is only one way to tell if atf is better or worse than the recommended 10w40
you would take 2 brand new never ridden kx500s, fill one with atf and the other with oil.
now run them under identical conditions until failure and see who wins.
just because you put ANY brand of oil in ANY bike and then 2 hours later you blow the trans, or clutch probably doesnt mean that oil caused your failure.
i run atf in my 94. i think it is the main reason i made it back to camp when i burned up my clutch at the dunes. at low rpm the plates would grab and pull me up hills but it would let go when the engine wound up. it was 95 degress out, and i had a 10 scoop paddle tire. when i did get back to camp i dumped the atf and i put in oil. the bike lost all forward drive completely. when i pulled the bike apart i took out what im pretty sure was the original clutch with the aluminum plates. there were grooves in each plate 1-2 mm deep. that was not ATFs fault in my opinion. now of course i know what some of you will say...........how do you know its the original clutch.. ........well i dont!!! ive had this bike 9 months. but i have taken apart a lot of bikes and its not hard to tell when something has been apart and has not.
i now have a new tusk racing clutch in with a fresh batch of atf and it works quite well. i like how my particular bike shifts with the atf so i continue to use it.
so there is yet another pretty useless testimonial for ATF over the manufacturer recommended lubricant.