Howdy everybody, I currently have a yz250 2 stroke and am looking at getting a 450 four stroke. I love my yz250 I have never had any problems with it and it is pretty easy to take care of. I have never owned a 4 stroke and am kinda scared. I have been told they are a pain in the ass to keep running. The bike would be for my dad and he does not ride very hard and only rides about 2-3 times a month. How often do you jsut adjust your valves and is it easy to do? And the final question, Honda or Yamaha? Thanks guys!