i have a 1985 honda 110 atc. i have noticed that when the motor gets hot it will slip out of gear. at first i thought the oil was too thin so i went from 10w30 to 10w40, past this i dont know what to do please post back

 

use motorcycle oil. car oil is not good for the clutches did you adjust the clutch.

 

My sons ATC70 had a similar problem. turned out the part which holds the damn thing in gear was broken.
It was called a 'shift drum stopper'. (Im sure the 110 has a similar part)

here is a pic (for the 70) -> http://dratv.stores.yahoo.net/70shdrst7.html

you'll need a book to open er' up - if you want to be able to put it back together.