Found this on E-BAY
Like new 27x12x12 rear and 27x9x12 front blackwater XT tires on polished alluminum ITP magnum wheels. Were bought for 2001 Sportsman 500. 100 light miles on tires.
OR would I be better off with 589's

I ride hardpack,trails,water and mud.
Will they mount right on?
Will I lose any top end
Will they be that much better then stock??
And what would a fair price be?

 

They should bolt right on A-OK because I think the hubs are the same. You'll lose some power, but might gain a mph or 2. If they're for a fair price, you could always buy new tires after ya wear these down and still be ahead cuz you got aluminum rims at a cheaper price than new.