I bought a 1998 YZ400F in July. I have ridden it raced it since ive had it. The power it has matches my cousins 2000 426 and i see no differences between the two. What i need to know though is how long this 1998 motor should last? because i want to know incase its time is coming to blow up on me and cost me thousands. Should i consider selling it soon and getting a newer YZ thumper? Thank you for your time and information.