if you can you need to ride both for a little bit. i think that youll find the yfz handles better, jumps better, and has quite a bit more power. the 450r is kinda tall, tippy and in my opinion down in the power department. the front end is very light which kinda makes jumping them a bitch. lets just say this, my buddy has a 450r. we ride trails, climb hills and mx. everytime we ride he says, " i shoulda bought a yfz". he has ridden ours and actually likes our better after 5 minutes of riding than he does his 450r. plus, who wants to kick the fuckin thing all the time? his doesnt start all that easily when cold thats for sure. my yfz sure fires right up tho with the push of a button...