The book says every 20 hours for a oil and filter change but this what the dealer said to me if it was his do the following
1st Change - after 2-3 tanks of fuel - Just incase theres any left over machining crap in your engine i change the filter and oil
2nd Change - 1st 20 hour service since your still wearing in the motor Oil + Filter
Then every 10 hours after that change the oil and filter
But now im thinking of changing to syn oil since all is worn in plus if you buy a real good oil you can gain a couple of hps plus it stops all the wearing too .
Looking at some at types of oil now up to $140.00 AU for 5 lts plus its sticky like chewing gum .
if you look at the manual it says first change in 20 hours then it is 160 hours from then on which is the same as the rest of the maintenace on every thing else.
if i did mine every 20hr. it would be once a weak or every other weak all summer long that would be alot of oil.
Air filter after every ride
Oil is around 10-30 depending on the riding. And always after a race. Filter is every other time or two. But only cause I'm putting about 15 to 20 hrs a week on the quad. and I got tired of changing the filter weekly.