Hey I just purchased a 03' Z400 and they want 300 bucks for a ten hour service. they said they check the top end of the bike and adjust the valves i can change the oil and all but does 300 bucks sound lie a lot? and after that for every 4 or 5 tanks of gas I do my own check ups what does that include besides changin oil and lube and tighting things down thanks for the help guys.