Seriously my wife has no trouble with her moto although Id say its just under 50hp (low powered). It was the first quad she has ever driven . If she was on something narrow ,tall and tippy like a cannibal or speed I might have thought about derating the engine but who want to ride a quad with thoise qualities?
Its all about instilling the requirement to respect the machine and your own capabilities. Just like what it says on the gas tank cover.