Depends on how fussy you are.
I do quite a few dirt roads, mud paths, low water crossings, etc. Gets pretty filthy.
So, down to the car wash (not the drive through kind!!
) , toss in some quarters and spray 'em down! Just don't spray UP underneath the tank or try to get in behind the side panels! And, back off a bit further than you would for a car. Stubborn stuff you can get with a wet rag.
Remember, motorcycle are ridden in the rain. If you don't try to force water where rain and road spray wouldn't go, you should be OK.
If you have a newer bike, or care more about the appearance, then you can spend a ton o money on the microfiber this, wax stuff that, cleaner something or other.
I spend my money on gas.