Avons are the first that most people throw away. We don't call them Skidmasters for nuttin'! Most popular option are probably Dunlop K-70s, look in the front section to find the 3.25s and 3.50s. They will work on either end. Non-directional. They are great handling, but a bit short on rear tire life, but for the price, they're still worth it. My personal choice that I went to after the K70s are Pirelli MT66s. Even better steering, traction, and life. Again front tires, but mount the one on the back backwards. Fantastic tires. Only about $20 more for theset from Bike Bandit. Bare's recommendation!
Bare