use 10-40 if thats what your bike calls for, if not figure out what your bike needs, i very highly doubt a manual will tell you to put atf in your bike
alrite..i got a manual comin in the mail but i wanna change the tranny before this wknd,and the manual wont be here by then so i was juss wonderin what u guys think i should use..
What your suppose to,not atf! People for what ever reason think it is a viable alternative. Funny,if it was they would say so in the manual. Some bizarre manufactures even recommend it in their bikes,not Suzuki!
I've run Type F ATF in a 99 KX80, 03 RM125, 05 RM125 and an 02 RM250. Been very happen with the performance of the ATF and have yet to suffer a gearbox failure in any of those bikes. The only reason we stopped running ATF was a sponsorship that supplied us with oil and the fact the the kid is on a 4 stroke now.
A search for ATF will provide plenty of reading but here's one to start.