I have pretty much decided on building a yz450 for street use, if I can find a wr for a good price I will go that route, however they are rare and more expensive, but say I do the yz450f, how much can I extend the oil changes? I know it has small oil capacity, so would buying a extended clutch case allow you to fill more oil, thus extending the service oil changes? What about an oil cooler? I know yamahas are dependable so If possible I would like to extend oil changes as much as possible without just risking the engine life. I know I know its a high performance race bike but rather not have weekly oil changes lol, I came from 600cc sportbikes with nice service intervals so I am spoiled in that regard:lol: I don't mind wrenching, actually enjoy it but not super often.