After about 3000 miles the stock rear tire on my WR250X was completely shot. I was going to just replace it with another Bridgestone BT-090 Battlax, but decided I wanted something with a little more grip. I've used Bridgestone BT-003's on another bike and really liked them, so that's what I went with. IMHO there is no reason to go wider on the tires for this bike, so I stuck with the stock sizes front and rear.

I got them at Motorcycle-Superstore.com. Delivery took just 2 days…
Front Tire: Bridgestone Battlax BT-003 (110/70ZR-17)
Rear Tire: Bridgestone Battlax BT-003 (140/70ZR-17)