I'll have to say the 06 YZ450F is AWESOME! I don't even have my Windhan bars or GYT risers yet... I ride a track on Maui where there's lots of clay in the soil that's slick when wet and hard packs quickly when dry. I'm thinking it's better to get wider tires (90 & 120) for increased traction. Is this a correct assumption and is it recommended? I'm not worried about losing a bit of power with the 450 but guess I would be concerned about engine wear. I'm thinking traction on our tight track is more important than increased weight in the air. I'm hearing the Maxxis IT 120 for the back. Does the Michellin S12 come in a 90? I don't think the Dunlops do. Thanks in advance.