As rogue 1970 said install  new sprockets  at the same time.  I run a  did atv x ring  chain(  i think fancy term for o ring  chain) , on both my 85 lt250r  and my sons 86 lt230 quadsport wraped around vortex  sprockets. . I have adjusted it twice in the first 16 hours  of ride time . I haven't  touched it since. 40 hours  on them now.  We run them very hard too.