Here are some weights for popular tires that I have gotten from web sites
These figures are for all 4 tires

25' tires
Stock Dunlop 64 lbs
Mudlites 68 lbs
ATR's 78 lbs
Bear Claws 92 lbs
Mud Runners 94 lbs


27" tires
Mudlites 108
Mudrunners 118 lbs
Bear Claws 124 lbs

Tire & wheel weight is some of the worst lbs you can add to your quad.
It effects handling, acceleration, and ride quality.
I don't think this applies so much to deep mud or snow though.
Hope this helps

 

Good infro.